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PREPARING FOR ICD-10-CM ANATOMY AND PATHOPHYSIOLOGY TRAINING © RMACI, 2015
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Page 1: PREPARING FOR ICD-10-CM ANATOMY AND … · 2015-11-04 · Modification (ICD-10-CM) promises to be one of the most significant changes to the administration of healthcare billing and

PREPARING FOR ICD-10-CM

ANATOMY AND PATHOPHYSIOLOGY TRAINING

© RMACI, 2015

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INTRODUCTION TO ANATOMY AND PATHOPHYSIOLOGY The transition to the International Classification of Diseases, 10th Edition, Clinical Modification (ICD-10-CM) promises to be one of the most significant changes to the administration of healthcare billing and reimbursement process. The entire structure of the diagnosis reporting system will change, effective October 1, 2015. This Anatomy and Pathophysiology Training video and the accompanying manual is the first step in the transition process. ICD-10-CM is substantially different than ICD-9-CM in a number of ways. CHARACTERISTIC

ICD-9

ICD-10

Number of characters

3–5 digits in length 3–7 characters in length

Number of codes Approximately 13,000 codes

Approximately 68,000 available codes

Types of characters First digit can be alpha (E or V) or numeric; digits 2–5 are numeric; most codes are all numeric

Character 1 is alpha; character 2 is numeric;

characters 3–7 are alpha or numeric

Code capacity Limited space for adding new codes

Flexible for adding new codes

Specificity Lacks detail Very specific

Laterality designations (right vs. left vs. bilateral)

Lacks laterality Has laterality

These are very straightforward characteristics that can be easily identified when comparing the two coding systems. However, one major element that is not immediately recognizable is the fact that ICD-10-CM is more “clinically” driven. Health care is very different in the 21st century than it was in 1979, when ICD-9-CM was introduced. Illnesses and diseases that were not identified in 1979 are now treated on a regular basis. Medical tests, vaccines, and procedures are now performed daily that had never been conceived of at that time. One major reason for the change to ICD-10, in addition to the reasons indicated above, is to help health care providers use diagnosis codes that are more consistent with the daily reality of clinical practice. This means that ICD-10-CM code selection will be more intuitive for physicians and other health

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care providers because codes are organized more logically than they were organized in ICD-9. That logical organization is based on two factors—patient anatomy and pathophysiology. However, we must first define these terms. KEY DEFINITIONS Anatomy—The study of the structure of the human body. The study of anatomy is understanding all of the pieces that comprise the human body. This includes the bones, muscles, nerves, etc. that every human has, or should have. In order to properly select ICD-10-CM codes, one must have a basic understanding of the human anatomy because the codes are organized based by anatomical system and/or by anomalies (abnormalities) to that anatomy. Physiology—The study of the function of the human body. Whereas “anatomy” examines the parts of the body, physiology studies how those parts work. It is vital to understand how parts work normally in order to report the diagnosis(es) when there is a malfunction or dysfunction in the body. Pathophysiology—The physiology of abnormal states. Many times, the purpose of medical care is to diagnose and treat the abnormal function of a body system or systems. A basic understanding of common “pathologies” will help those involved in the billing/coding process more accurately assist in the use of the proper diagnosis code(s). THE BASICS OF MEDICAL TERMINOLOGY To those who have not undergone formal medical training, many “medical words” may seem difficult to understand and, in some cases, frightening. However, there are three common parts to almost all medical terms. Once we understand the basic structure, understanding what these medical terms mean becomes much easier. Almost all medical terminology has two or three parts. They are:

PREFIX + ROOT WORD + SUFFIX Almost all root words have their origin in either Greek or Latin. Every medical term has a root word and most have either a prefix or suffix. Some have both a prefix and suffix. By putting the pieces together and understanding the meanings of the prefixes, suffixes, and roots, you can understand the nature of the illness, even if you have not previously studied that specific word.

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We will begin with some common and general terms and then we will narrow our focus in the latter half of this video/manual to address issues specific to your specialty. ROOT WORDS Root words come from one of five places:

• Roots of the body • Roots of color • Roots of description • Roots of position • Roots of quantity

ROOTS OF THE BODY

Body part or component Greek root in English Latin root in English

abdomen lapar(o)- abdomin-

aorta aort(o)- aort(o)-

arm brachi(o)- -

artery arteri(o)- -

back - dors-

bladder cyst(o)- vesic(o)-

blood haemat-, hemat- (haem-, hem-) sangui-, sanguine-

blood clot thromb(o)- -

blood vessel angi(o)- vascul-, vas-

bone oste(o)- ossi-

bone marrow, marrow myel(o)- medull-

brain encephal(o)- cerebr(o)-, pector-

breast mast(o)- mamm(o)-

ear ot(o)- aur(i)-

eggs, ova oo- ov-

eye ophthalm(o)- ocul(o)-

eyelid blephar(o)- cili-, palpebr-

fallopian tubes salping(o)- -

fat, fatty tissue lip(o)- adip-

finger dactyl(o)- digit-

gallbladder cholecyst(o)- fell-

gland aden(o)- -

head cephal(o)- capit(o)-

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Body part or component Greek root in English Latin root in English

heart cardi(o)- cordi-

intestine enter(o)- -

kidney nephr(o)- ren-

liver hepat(o)-, (hepatic-) jecor-

lungs pneumon- pulmon(i)-, (pulmo-)

marrow, bone marrow myel(o)- medull-

mind psych- ment-

mouth stomat(o)- or-

muscle my(o)- -

nail onych(o)- ungui-

nerve; the nervous system neur(o)- nerv-

nose rhin(o)- nas-

ovary oophor(o)- ovari(o)-

rib cage thorac(i)-, thorac(o)- -

skin dermat(o)-, (derm-) cut-, cuticul-

skull crani(o)- -

stomach gastr(o)- ventr(o)-

testis orchi(o)-, orchid(o)- -

throat (upper throat cavity) pharyng(o)- -

throat (lower throat cavity/voice box]) laryng(o)- -

uterus hyster(o)-, metr(o)- uter(o)-

vagina colp(o)- vagin-

vein phleb(o)- ven-

vulva episi(o)- vulv-

wrist carp(o)- carp(o)-

Frequently, vowels (usually the letter “O”) are added to the end of the root in order to facilitate a connection to a suffix that begins with a consonant.

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ROOTS OF COLOR

Color Greek root in English Latin root in English

black melano- nigr-

blue cyano- –

green chlor(o)- vir-

red erythr(o)-, rhod(o)- rub-, rubr-

red-orange cirrh(o)- –

white leuc-, leuk- alb-

yellow xanth(o)- flav-, jaun- [French]

ROOTS OF DESCRIPTION

Description Greek root in English Latin root in English

bad, incorrect cac(o)-, dys- mal(e)-

bent, crooked ankyl(o)- prav(i)-

big mega-, megal(o)- magn(i)-

cold cry(o)- frig(i)-

dead necr(o)- mort-

female, feminine thely- -

fast tachy- celer-

flat platy- plan(i)-

great mega-, megal(o)- magn(i)-

hard scler(o)- dur(i)-

heavy bar(o)- grav(i)-

huge megal(o)- magn(i)-

incorrect, bad cac(o)-, dys- mal(e)-

long macr(o)- long(i)-

narrow sten(o)- angust(i)-

short brachy- brev(i)-

small micr(o)- parv(i)- (rare)

slow brady- tard(i)-

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ROOTS OF POSITION

Description Greek root in English Latin root in English

around peri- circum-

left levo- laev(o)-, sinistr-

middle mes(o)- medi-

right dexi(o)- dextr(o)-

surrounding peri- circum-

DESCRIPTIVE WORDS—POSITION

Description Definition

anterior/ventral at or near the front surface of the body

posterior/dorsal at or near the back surface of the body

superior above

inferior below

lateral side

distal farthest from center

proximal nearest to center

medial middle

supine face up or palm up

prone face down or palm down

sagittal vertical body plane, divides the body into equal right and left sides

transverse horizontal body plane, divides the body into top and bottom sections

coronal vertical body plane, divides the body into front and back sections

ROOTS OF QUANTITY

Description Greek root in English Latin root in English

double diplo- dupli-

equal iso- equi-

few oligo- pauci-

half hemi- semi-

many, much poly- multi-

twice dis- bis-

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COMMON PREFIXES AND SUFFIXES

Prefix/Suffix Meaning Examples a-/an- without/none anemia, anencephalic -algia pain neuralgia arth-/arthro- pertaining to the joints or limbs arthritis -asthenia weakness myasthenia -centesis puncture a cavity to remove fluid amniocentesis -ectomy to cut out (remove) appendectomy, tonsillectomy -emia blood anemia -gram image (X-ray, CT, MRI, Ultrasound) mammogram -graphy/-graph recording an image mammography hyper- excessive, above hypergastric hypo- deficient, below hypogastric -ia/-iasis condition, abnormality pneumonia -itis inflammation tonsillitis, appendicitis macro- large macrostomia mega-/-megaly enlarged organomegaly micro- small microstomia -ology/-ologist to study/specialize in cardiologist, nephrologist -oma/-omata tumor, bulk, volume melanoma -opathy disease of arthropathy -opexy surgical fixation nephropexy -oplasty surgical repair rhinoplasty -orrhaphy surgical repair/suture herniorrhaphy -orrhea flow or discharge amenorrhea -osis abnormal condition cyanosis -ostomy to make a mouth (opening) colostomy -otomy to cut into tracheotomy -otripsy crushing, destroying lithotripsy -pepsia digestion dyspepsia -phagia eating polyphagia -plasia growth hyperplasia -plegia paralysis paraplegia -pnea breathing apnea -scopy/-scopic to look, observe colonoscopy

More specific roots, prefixes, and suffixes will be discussed when we begin to address the anatomy and pathophysiology associated with individual specialties.

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REVIEW ITEMS

1. When a patient has inflammation of the kidney, what is it called?

___________________________________________

2. What does it mean when a patient has a colposcopy?

___________________________________________

3. When a patient has a vesical fistula, what organ is affected?

___________________________________________

4. When a patient has a blood disorder, what type of specialist will they most likely

see? _______________________________________

5. When a patient has thrombophlebitis, what does it mean?

___________________________________________

6. What does pneumonia mean?

___________________________________________

7. What organ system is affected by arteriosclerosis?

___________________________________________

8. What is wrong with the patient when they have a megaloureter?

___________________________________________

9. How is pharyngitis different than laryngitis?

___________________________________________

10. When a patient has polycystic ovaries, what abnormality is occurring?

___________________________________________

11. What does it mean when a patient has arthropathy?

___________________________________________

12. What does it mean if the patient reports polyphagia?

___________________________________________

(Answers are found on page 12.)

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THE ORGANIZATION OF ICD-10-CM AND ITS RELATIONSHIP TO ANATOMY AND PATHOPHYSIOLOGY As indicated previously, ICD-10-CM is much more clinically oriented than ICD-9-CM. That is not to say that the organization of ICD-10-CM is dramatically different. The following chart illustrates the comparison between the two code sets.

ICD-10 Chapter

Description

Code

Range

Equivalent ICD-9 Codes

1 Certain Infectious and Parasitic Diseases A00-B99 001-139

2 Neoplasms C00-D49 140-239 3 Disease of the Blood and Blood Forming

Organs and Certain Disorders Involve the Immune Mechanism

D50-D89 280-289

4 Endocrine, Nutritional, and Metabolic Diseases E00-E89 240-279 5 Mental and Behavior Disorders F01-F99 290-319 6 Diseases of the Nervous Systems G00-G99 320-389 7 Diseases of the Eye and Adnexa H00-H59 320-389 8 Diseases of Ear and Mastoid Process H60-H95 320-389 9 Diseases of the Circulatory System I00-I99 390-459

10 Diseases of the Respiratory System J00-J99 460-519 11 Diseases of the Digestive System K00-K95 520-579 12 Diseases of the Skin and Subcutaneous Tissue L00-L99 680-709 13 Diseases of the Musculoskeletal System and

Connective Tissue M00-M99 710-739

14 Diseases of the Genitourinary System N00-N99 580-629 15 Pregnancy, Childbirth, and the Puerperium O00-O9A 630-679 16 Certain Conditions Originating in the Perinatal

Period P00-P96 760-779

17 Congenital Malformations, Deformations, and Chromosomal Abnormalities

Q00-Q99 740-759

18 Symptoms, Signs, and Abnormal Clinical and Laboratory Findings, Not Elsewhere Classified

R00-R99 780-799

19 Injury, Poisoning, and Certain Other Consequences of External Causes

S00-T88 800-999

20 External Causes of Morbidity V01-Y99 E800-E999

21 Factors Influencing Health Status and Contact with Health Services

Z00-Z99 V01-V91

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The fundamental structures of the code sets are not vastly different. ICD-9-CM has 17 chapters and 2 chapters of supplementary classifications (the V & E codes). ICD-10-CM has 21 chapters. The differences are as follows:

• The former supplementary chapters have been incorporated as an integral part of the code set (chapters 20 & 21).

• Chapter 6 in ICD-9-CM (Diseases of the Nervous System and Sense Organs) has been split into three chapters in ICD-10-CM.

o Chapter 6—Diseases of the Nervous Systems o Chapter 7—Diseases of the Eye and Adnexa o Chapter 8—Diseases of the Ear and Mastoid Process

• The chapters have been slightly reordered. The chapters that require significant anatomic knowledge are:

6 Diseases of the Nervous Systems 7 Diseases of the Eye and Adnexa 8 Diseases of Ear and Mastoid Process 9 Diseases of the Circulatory System

10 Diseases of the Respiratory System 11 Diseases of the Digestive System 12 Diseases of the Skin and Subcutaneous Tissue 13 Diseases of the Musculoskeletal System and

Connective Tissue 14 Diseases of the Genitourinary System 15 Pregnancy, Childbirth, and the Puerperium 16 Certain Conditions Originating in the Perinatal

Period 17 Congenital Malformations, Deformations, and

Chromosomal Abnormalities

The chapters that require significant knowledge concerning pathophysiology are:

1 Certain Infectious and Parasitic Diseases

5 Mental and Behavioral Disorders 18 Symptoms, Signs, and Abnormal Clinical and

Laboratory Findings, Not Elsewhere Classified 19 Injury, Poisoning, and Certain Other

Consequences of External Causes 20 External Causes of Morbidity

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The chapters that require a combination of anatomy and pathophysiology knowledge are:

2 Neoplasms

3 Disease of the Blood and Blood Forming Organs and Certain Disorders Involve the

Immune Mechanism 4 Endocrine, Nutritional, and Metabolic Diseases

21 Factors Influencing Health Status and Contact with Health Services

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ANSWERS TO REVIEW ITEMS

1. When a patient has inflammation of the kidney, what is it called?

_______nephritis_____________________________

2. What does it mean when a patient has a colposcopy?

_______to look at or observe the vagina (& cervix)__

3. When a patient has a vesical fistula, what organ is affected?

___________bladder _________________________

4. When a patient has a blood disorder, what type of specialist will they most likely

see? ________hemotologist____________________

5. When a patient has thrombophlebitis, what does it mean?

___inflammation of the vein caused by a blood clot__

6. What does pneumonia mean?

__condition/abnormality of the lungs_____________

7. What organ system is affected by arteriosclerosis?

______cardiovascular (arteries)__________________

8. What is wrong with the patient when they have a megaloureter?

_______an enlarged ureter_____________________

9. How is pharyngitis different than laryngitis?

_upper throat inflammation vs. lower throat inflammation_

10. When a patient has polycystic ovaries, what abnormality is occurring?

_multiple cysts formed on the ovaries_____________

11. What does it mean when a patient has arthropathy?

____abnormality of a joint___________________

12. What does it mean if the patient reports polyphagia?

____excessive eating/appetite_________________

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ANATOMY AND PATHOPHYSIOLOGY FOR DERMATOLOGY The Dermatologist specializes in the treatment of conditions related to the Integumentary System The approach to the anatomy and physiology training for this specialty will be as follows:

• Anatomy—what are the major organs that are part of the system and how are they supposed to work?

• Terminology—what are the major medical terms associated with these organs/this system?

• Pathophysiology—what are the common diseases or dysfunctions that occur in association with these organs?

The component parts/functions of the system that will be addressed are as follows:

• Integumentary System • Neoplasms of the Skin and Subcutaneous Tissues

SKIN AND SUBCUTANEOUS TISSUES (INTEGUMENTARY SYSTEM)

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The integumentary system is an organ system consisting of the skin, hair, nails, and exocrine glands. The skin is only a few millimeters thick yet is by far the largest organ in the body. The average person’s skin weighs 10 pounds and has a surface area of almost 20 square feet. Skin forms the body’s outer covering and forms a barrier to protect the body from chemicals, disease, UV light, and physical damage. Hair and nails extend from the skin to reinforce the skin and protect it from environmental damage. The exocrine glands of the integumentary system produce sweat, oil, and wax to cool, protect, and moisturize the skin’s surface. INTEGUMENTARY SYSTEM ANATOMY Epidermis The epidermis is the most superficial layer of the skin that covers almost the entire body surface. The epidermis rests upon and protects the deeper and thicker dermis layer of the skin. Structurally, the epidermis is only about a tenth of a millimeter thick but is made of 40 to 50 rows of stacked squamous epithelial cells. The epidermis is an avascular region of the body, meaning that it does not contain any blood or blood vessels. The cells of the epidermis receive all of their nutrients via diffusion of fluids from the dermis. The epidermis is made of several specialized types of cells. Almost 90% of the epidermis is made of cells known as keratinocytes. Keratinocytes develop from stem cells at the base of the epidermis and begin to produce and store the protein keratin. Keratin makes the keratinocytes very tough, scaly and water-resistant. At about 8% of epidermal cells, melanocytes form the second most numerous cell type in the epidermis. Melanocytes produce the pigment melanin to protect the skin from ultraviolet radiation and sunburn. Langerhans cells are the third most common cells in the epidermis and make up just over 1% of all epidermal cells. Langerhans cells’ role is to detect and fight pathogens that attempt to enter the body through the skin. Finally, Merkel cells make up less than 1% of all epidermal cells but have the important function of sensing touch. Merkel cells form a disk along the deepest edge of the epidermis where they connect to nerve endings in the dermis to sense light touch. The epidermis in most of the body is arranged into 4 distinct layers. In the palmar surface of the hands and plantar surface of the feet, the skin is thicker than in the rest of the body and there is a fifth layer of epidermis. The deepest region of the epidermis is the stratum basale, which contains the stem cells that reproduce to form all of the other cells of the epidermis. The cells of the stratum basale include cuboidal keratinocytes, melanocytes, and Merkel cells. Superficial to stratum basale is the stratum spinosum layer where Langerhans cells are found along with many rows of spiny keratinocytes. The spines found here are cellular projections called desmosomes that form between keratinocytes to hold them together and resist friction. Just superficial to the stratum spinosum is the stratum granulosum, where keratinocytes begin to produce waxy lamellar granules to waterproof the skin. The keratinocytes in

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the stratum granulosum are so far removed from the dermis that they begin to die from lack of nutrients. In the thick skin of the hands and feet, there is a layer of skin superficial to the stratum granulosum known as the stratum lucidum. The stratum lucidum is made of several rows of clear, dead keratinocytes that protect the underlying layers. The outermost layer of skin is the stratum corneum. The stratum corneum is made of many rows of flattened, dead keratinocytes that protect the underlying layers. Dead keratinocytes are constantly being shed from the surface of the stratum corneum and being replaced by cells arriving from the deeper layers.

Dermis The dermis is the deep layer of the skin found under the epidermis. The dermis is mostly made of dense irregular connective tissue along with nervous tissue, blood, and blood vessels. The dermis is much thicker than the epidermis and gives the skin its strength and elasticity. Within the dermis there are two distinct regions: the papillary layer and the reticular layer. The papillary layer is the superficial layer of the dermis that borders on the epidermis. The papillary layer contains many finger-like extensions called dermal papillae that protrude superficially towards the epidermis. The dermal papillae increase the surface area of the dermis and contain many nerves and blood vessels that are projected toward the surface of the skin. Blood flowing through the dermal papillae provide nutrients and oxygen for the cells of the epidermis. The nerves of the dermal papillae are used to feel touch, pain, and temperature through the cells of the epidermis.

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The deeper layer of the dermis, the reticular layer, is the thicker and tougher part of the dermis. The reticular layer is made of dense irregular connective tissue that contains many tough collagen and stretchy elastin fibers running in all directions to provide strength and elasticity to the skin. The reticular layer also contains blood vessels to support the skin cells and nerve tissue to sense pressure and pain in the skin. Hypodermis Deep to the dermis is a layer of loose connective tissues known as the hypodermis, subcutis, or subcutaneous tissue. The hypodermis serves as the flexible connection between the skin and the underlying muscles and bones as well as a fat storage area. Areolar connective tissue in the hypodermis contains elastin and collagen fibers loosely arranged to allow the skin to stretch and move independently of its underlying structures. Fatty adipose tissue in the hypodermis stores energy in the form of triglycerides. Adipose also helps to insulate the body by trapping body heat produced by the underlying muscles. Hair Hair is an accessory organ of the skin made of columns of tightly packed dead keratinocytes found in most regions of the body. The few hairless parts of the body include the palmar surface of the hands, plantar surface of the feet, lips, labia minora, and glans penis. Hair helps to protect the body from UV radiation by preventing sunlight from striking the skin. Hair also insulates the body by trapping warm air around the skin. The structure of hair can be broken down into 3 major parts: the follicle, root, and shaft. The hair follicle is a depression of epidermal cells deep into the dermis. Stem cells in the follicle reproduce to form the keratinocytes that eventually form the hair while melanocytes produce pigment that gives the hair its color. Within the follicle is the hair root, the portion of the hair below the skin’s surface. As the follicle produces new hair, the cells in the root push up to the surface until they exit the skin. The hair shaft consists of the part of the hair that is found outside of the skin. The hair shaft and root are made of 3 distinct layers of cells: the cuticle, cortex, and medulla. The cuticle is the outermost layer made of keratinocytes. The keratinocytes of the cuticle are stacked on top of each other like shingles so that the outer tip of each cell points away from the body. Under the cuticle are the cells of the cortex that form the majority of the hair’s width. The spindle-shaped and tightly packed cortex cells contain pigments that give the hair its color. The innermost layer of the hair, the medulla, is not present in all hairs. When present, the medulla usually contains highly pigmented cells full of keratin. When the medulla is absent, the cortex continues through the middle of the hair.

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Nails Nails are accessory organs of the skin made of sheets of hardened keratinocytes and found on the distal ends of the fingers and toes. Fingernails and toenails reinforce and protect the end of the digits and are used for scraping and manipulating small objects. There are 3 main parts of a nail: the root, body, and free edge. The nail root is the portion of the nail found under the surface of the skin. The nail body is the visible external portion of the nail. The free edge is the distal end portion of the nail that has grown beyond the end of the finger or toe. Nails grow from a deep layer of epidermal tissue known as the nail matrix, which surrounds the nail root. The stem cells of the nail matrix reproduce to form keratinocytes, which in turn produce keratin protein and pack into tough sheets of hardened cells. The sheets of keratinocytes form the hard nail root that slowly grows out of the skin and forms the nail body as it reaches the skin’s surface. The cells of the nail root and nail body are pushed toward the distal end of the finger or toe by new cells being formed in the nail matrix. Under the nail body is a layer of epidermis and dermis known as the nail bed. The nail bed is pink in color due to the presence of capillaries that support the cells of the nail body. The proximal end of the nail near the root forms a whitish crescent shape known as the lunula where a small amount of nail matrix is visible through the nail body. Around the proximal and lateral edges of the nail is the eponychium, a layer of epithelium that overlaps and covers the edge of the nail body. The eponychium helps to seal the edges of the nail to prevent infection of the underlying tissues. Sudoriferous Glands Sudoriferous glands are exocrine glands found in the dermis of the skin and commonly known as sweat glands. There are 2 major types of sudoriferous glands: eccrine sweat glands and apocrine sweat glands. Eccrine sweat glands are found in almost every region of the skin and produce a secretion of water and sodium chloride. Eccrine sweat is delivered via a duct to the surface of the skin and is used to lower the body’s temperature through evaporative cooling. Apocrine sweat glands are found in mainly in the axillary and pubic regions of the body. The ducts of apocrine sweat glands extend into the follicles of hairs so that the sweat produced by these glands exits the body along the surface of the hair shaft. Apocrine sweat glands are inactive until puberty, at which point they produce a thick, oily liquid that is consumed by bacteria living on the skin. The digestion of apocrine sweat by bacteria produces body odor. Sebaceous Glands Sebaceous glands are exocrine glands found in the dermis of the skin that produce an oily secretion known as sebum. Sebaceous glands are found in every part of the skin except for the thick skin of the palms of the hands and soles of the feet. Sebum is produced in the sebaceous glands and carried through ducts to the surface of the skin

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or to hair follicles. Sebum acts to waterproof and increase the elasticity of the skin. Sebum also lubricates and protects the cuticles of hairs as they pass through the follicles to the exterior of the body. PHYSIOLOGY OF THE INTEGUMENTARY SYSTEM Keratinization Keratinization, also known as cornification, is the process of keratin accumulating within keratinocytes. Keratinocytes begin their life as offspring of the stem cells of the stratum basale. Young keratinocytes have a cuboidal shape and contain almost no keratin protein at all. As the stem cells multiply, they push older keratinocytes towards the surface of the skin and into the superficial layers of the epidermis. By the time keratinocytes reach the stratum spinosum, they have begun to accumulate a significant amount of keratin and have become harder, flatter, and more water resistant. As the keratinocytes reach the stratum granulosum, they have become much flatter and are almost completely filled with keratin. At this point the cells are so far removed from the nutrients that diffuse from the blood vessels in the dermis that the cells go through the process of apoptosis. Apoptosis is programmed cell death where the cell digests its own nucleus and organelles, leaving only a tough, keratin-filled shell behind. Dead keratinocytes moving into the stratum lucidum and stratum corneum are very flat, hard, and tightly packed so as to form a keratin barrier to protect the underlying tissues. Temperature Homeostasis Being the body’s outermost organ, the skin is able to regulate the body’s temperature by controlling how the body interacts with its environment. In the case of the body entering a state of hyperthermia, the skin is able to reduce body temperature through sweating and vasodilation. Sweat produced by sudoriferous glands delivers water to the surface of the body where it begins to evaporate. The evaporation of sweat absorbs heat and cools the body’s surface. Vasodilation is the process through which smooth muscle lining the blood vessels in the dermis relax and allow more blood to enter the skin. Blood transports heat through the body, pulling heat away from the body’s core and depositing it in the skin where it can radiate out of the body and into the external environment. In the case of the body entering a state of hypothermia, the skin is able to raise body temperature through the contraction of arrector pili muscles and through vasoconstriction. The follicles of hairs have small bundles of smooth muscle attached to their base called arrector pili muscles. The arrector pili form goose bumps by contracting to move the hair follicle and lifting the hair shaft upright from the surface of the skin. This movement results in more air being trapped under the hairs to insulate the surface of the body. Vasoconstriction is the process of smooth muscles in the walls of blood vessels in the dermis contracting to reduce the flood of blood to the skin. Vasoconstriction permits the skin to cool while blood stays in the body’s core to maintain heat and circulation in the vital organs.

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Vitamin D Synthesis Vitamin D, an essential vitamin necessary for the absorption of calcium from food, is produced by ultraviolet (UV) light striking the skin. The stratum basale and stratum spinosum layers of the epidermis contain a sterol molecule known as 7-dehydrocholesterol. When UV light present in sunlight or tanning bed lights strikes the skin, it penetrates through the outer layers of the epidermis and strikes some of the molecules of 7-dehydrocholesterol, converting it into vitamin D3. Vitamin D3 is converted in the kidneys into calcitriol, the active form of vitamin D. Protection The skin provides protection to its underlying tissues from pathogens, mechanical damage, and UV light. Pathogens, such as viruses and bacteria, are unable to enter the body through unbroken skin due to the outermost layers of epidermis containing an unending supply of tough, dead keratinocytes. This protection explains the necessity of cleaning and covering cuts and scrapes with bandages to prevent infection. Minor mechanical damage from rough or sharp objects is mostly absorbed by the skin before it can damage the underlying tissues. Epidermal cells reproduce constantly to quickly repair any damage to the skin. Melanocytes in the epidermis produce the pigment melanin, which absorbs UV light before it can pass through the skin. UV light can cause cells to become cancerous if not blocked from entering the body. Skin Color Human skin color is controlled by the interaction of 3 pigments: melanin, carotene, and hemoglobin. Melanin is a brown or black pigment produced by melanocytes to protect the skin from UV radiation. Melanin gives skin its tan or brown coloration and provides the color of brown or black hair. Melanin production increases as the skin is exposed to higher levels of UV light resulting in tanning of the skin. Carotene is another pigment present in the skin that produces a yellow or orange cast to the skin and is most noticeable in people with low levels of melanin. Hemoglobin is another pigment most noticeable in people with little melanin. Hemoglobin is the red pigment found in red blood cells, but can be seen through the layers of the skin as a light red or pink color. Hemoglobin is most noticeable in skin coloration during times of vasodilation when the capillaries of the dermis are open to carry more blood to the skin’s surface. Cutaneous Sensation The skin allows the body to sense its external environment by picking up signals for touch, pressure, vibration, temperature, and pain. Merkel disks in the epidermis connect to nerve cells in the dermis to detect shapes and textures of objects contacting the skin. Corpuscles of touch are structures found in the dermal papillae of the dermis that also detect touch by objects contacting the skin. Lamellar corpuscles found deep in the dermis sense pressure and vibration of the skin. Throughout the dermis there are many free nerve endings that are simply neurons with their dendrites spread throughout the dermis. Free nerve endings may be sensitive to pain, warmth, or cold. The density of these sensory receptors in the skin varies throughout the body, resulting in some

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regions of the body being more sensitive to touch, temperature, or pain than other regions. Excretion In addition to secreting sweat to cool the body, eccrine sudoriferous glands of the skin also excrete waste products out of the body. Sweat produced by eccrine sudoriferous glands normally contains mostly water with many electrolytes and a few other trace chemicals. The most common electrolytes found in sweat are sodium and chloride, but potassium, calcium, and magnesium ions may be excreted as well. When these electrolytes reach high levels in the blood, their presence in sweat also increases, helping to reduce their presence within the body. In addition to electrolytes, sweat contains and helps to excrete small amounts of metabolic waste products such as lactic acid, urea, uric acid, and ammonia. Finally, eccrine sudoriferous glands can help to excrete alcohol from the body of someone who has been drinking alcoholic beverages. Alcohol causes vasodilation in the dermis, leading to increased perspiration as more blood reaches sweat glands. The alcohol in the blood is absorbed by the cells of the sweat glands, causing it to be excreted along with the other components of sweat. KEY TERMS Term Meaning Examples Adip/o, lip/o, steat/o Fat Skin Cutane/o, dermat/o, derm/o

Skin Subcutaneous tissue, dermatitis

Hidr/o Sweat Kerat/o Horny tissue, hard Keratosis Melan/o Black Melanoma Myc/o Fungus Dermatomycosis Onych/o Nail Onychomycosis Scler/o Hardening Scleroderma Squam/o Scale Squamous cells Epi- Above or upon Outer layer of skin -oid Resembling Dermoid

Common Signs and Symptoms

• Disturbance of skin sensation-a variance from the normal state, including lack of sensation, hypersensitivity, paresthesia (pins and needles), etc.

• Rash—a skin eruption • Swelling, masses, or lump—an abnormal growth that is localized to the skin and

underlying layers of tissue • Cyanosis—a bluish coloration of the skin • Pallor—clammy skin • Flushing—an excessive pink or red tone to the skin

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PATHOPHYSIOLOGY OF THE INTEGUMENTARY SYSTEM • Abscess--an enclosed collection of liquefied tissue, known as pus, somewhere in

the body. It is the result of the body's defensive reaction to foreign material. There are two types of abscesses, septic and sterile. Most abscesses are septic, which means that they are the result of an infection. Septic abscesses can occur anywhere in the body. Only a germ and the body's immune response are required. In response to the invading germ, white blood cells gather at the infected site and begin producing chemicals called enzymes that attack the germ by digesting it. These enzymes act like acid, killing the germs and breaking them down into small pieces that can be picked up by the circulation and eliminated from the body. Unfortunately, these chemicals also digest body tissues. In most cases, the germ produces similar chemicals. The result is a thick, yellow liquid—pus—containing digested germs, digested tissue, white blood cells, and enzymes.

• Acne--Acne is a skin disease marked by pimples on the face, chest, and back. It is the most common skin disease. Increased levels of androgens (male hormones) cause the sebaceous glands to secrete an excessive amount of sebum into hair follicles. The excess sebum combines with dead, sticky skin cells to form a hard plug that blocks the follicle. Bacteria that normally lives on the skin then invades the blocked follicle. Weakened, the follicle bursts open, releasing the sebum, bacteria, skin cells, and white blood cells into the surrounding tissues. A pimple then forms.

• Alopecia Areata--Is an autoimmune skin disease that causes the body’s immune system to attack the hair follicles, causing baldness in patches.

• Athlete’s foot--Athlete’s foot is a common fungus infection in which the skin between the toes becomes itchy and sore, cracking and peeling away. Properly known as tinea pedis, the infection received its common name because the infection causing fungi grow well in warm, damp areas such as in and around swimming pools, showers, and locker rooms (areas commonly used by athletes).

• Burns--There are few threats more serious to the skin than burns. Burns are injuries to tissues caused by intense heat, electricity, UV radiation (sunburn), or certain chemicals (such as acids).

• Cellulitis--Cellulitis is a spreading bacterial infection just below the skin surface. It is most commonly caused by Streptococcus pyogenes or Staphylococcus aureus. The word "cellulitis" actually means "inflammation of the cells." Specifically, cellulitis refers to an infection of the tissue just below the skin surface. In humans, the skin and the tissues under the skin are the most common locations for microbial infection. Skin is the first defense against invading bacteria and other microbes. An infection can occur when this normally strong barrier is damaged due to surgery, injury, or a burn. Even something as small as a scratch or an insect bite allows bacteria to enter the skin, which may lead to an infection. Usually, the immune system kills any invading bacteria, but sometimes the bacteria are able to grow and cause an infection.

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Once past the skin surface, the warmth, moisture, and nutrients allow bacteria to grow rapidly. Disease-causing bacteria release proteins called enzymes which cause tissue damage. The body's reaction to damage is inflammation which is characterized by pain, redness, heat, and swelling. This red, painful region grows bigger as the infection and resulting tissue damage spread. An untreated infection may spread to the lymphatic system (acute lymphangitis), the lymph nodes (lymphadenitis), the bloodstream (bacteremia), or into deeper tissues. Cellulitis most often occurs on the face, neck, and legs.

• Dermatitis--Dermatitis is any inflammation of the skin. There are many types of dermatitis and most are characterized by a pink or red rash that itches. Two common types are contact dermatitis and seborrheic dermatitis.

o Contact dermatitis is type of skin inflammation that results from exposure to irritants (irritant contact dermatitis) or allergens (allergic contact dermatitis). Irritant contact dermatitis can be divided into forms caused by chemical irritants and those caused by physical irritants. Common chemical irritants implicated include solvents (alcohol, xylene, turpentine, esters, acetone, ketones, and others); metalworking fluids (neat oils, water-based metalworking fluids with surfactants); latex; kerosene; ethylene oxide; surfactants in topical medications and cosmetics (sodium lauryl sulfate); alkalis (drain cleaners, strong soap with lye residues). Physical irritant contact dermatitis may most commonly be caused by low humidity from air conditioning. Also, many plants directly irritate the skin. Although less common than ICD, ACD is accepted to be the most prevalent form of immunotoxicity found in humans. By its allergic nature, this form of contact dermatitis is a hypersensitive reaction that is atypical within the population. The mechanisms by which these reactions occur are complex, with many levels of fine control. Their immunology centres on the interaction of immunoregulatory cytokines and discrete subpopulations of T lymphocytes. Allergens include nickel, gold, balsam of Peru (Myroxylon pereirae), chromium and the oily coating from plants of the Toxicodendron genus: poison ivy, poison oak, and poison sumac.

o Seborrheic dermatitis, an advanced form of seborrhea, is a non-contagious skin disease that causes excessive oiliness of the skin, most commonly in the scalp, caused by overproduction of sebum, the substance produced by the body to lubricate the skin where hair follicles are present. Seborrhea is the form of the disease where oiliness only occurs without redness and scaling. The disease commonly occurs in infants, middle-aged people, and the elderly, and is commonly known in infants as cradle cap.

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Lymphangitis--an inflammation of one or more lymphatic vessels, usually resulting from an acute streptococcal infection of one of the extremities. It is characterized by fine red streaks extending from the infected area to the axilla or groin and by fever, chills, headache, and myalgia. The infection may spread to the bloodstream. Penicillin and hot soaks are usually prescribed; aseptic technique is important to avoid contagion. Paronychia--Is an often tender infection or inflammation around the base of the nail fold. It can start suddenly (acute paronychia) or gradually (chronic paronychia). Chronic paronychia is a gradual process and much more difficult to treat. It may start in one nail fold but often spreads to several others. Each affected nail fold (the skin that lies next to the nail) becomes swollen and lifted above the nail. It may be red and tender from time to time, and sometimes a little thick pus (white, yellow or green) can be expressed from under the cuticle. • Pruritus--intense itching, as a symptom of systemic disease (e.g. drug

hypersensitivity, obstructive jaundice, endocrine disease, renal dysfunction and some malignancies), skin disease (e.g. psoriasis, eczema, urticaria, lichen planus, scabies) or as a side-effect of opioid analgesics

• Psoriasis--Psoriasis is a chronic (long-term) skin disease characterized by inflamed lesions with silvery-white scabs of dead skin. Normal skin cells mature and replace dead skin cells every twenty-eight to thirty days. Psoriasis causes skin cells to mature in less than a week.

• Ulcer--a local defect, or excavation of the surface, of an organ or tissue, produced by sloughing of necrotic inflammatory tissue. It can be caused either by prolonged exterior pressure or other causes (nonpressure ulcer).

• Warts--Warts are small growths caused by a viral infection of the skin or mucous membrane. The virus infects the surface layer. Warts are contagious. They can easily pass from person to person. They can also pass from one area of the body to another on the same person. Hand warts grow around the nails, on the fingers, and on the backs of the hands. They appear mostly in areas where the skin is broken. Foot warts (also called plantar warts) usually appear on the ball of the foot, the heel, or the flat part of the toes. Foot warts do not stick up above the surface like hand warts. If left untreated, they can grow in size and spread into clusters of several warts. If located on a pressure point of the foot, these warts can be painful.

NEOPLASMS OF THE SKIN AND SUBCUTANEOUS TISSUES

Neoplasms are an abnormal new growth of tissue that grows by cellular proliferation more rapidly than normal, continues to grow after the stimuli that initiated the new growth cease, shows partial or complete lack of structural organization and functional

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coordination with the normal tissue, and usually forms a distinct mass of tissue which may be either benign or malignant. There are four classifications of neoplasms:

• Benign--A benign neoplasm is a mass of cells (tumor) that lacks the ability to invade neighboring tissue or metastasize. These characteristics are required for a tumor to be defined as cancerous and therefore benign tumors are non-cancerous. Also, benign tumors generally have a slower growth rate than malignant tumors and the tumor cells are usually more differentiated (cells have normal features). Benign tumors are typically surrounded by an outer surface (fibrous sheath of connective tissue) or remain with the epithelium. Common examples of benign tumors include moles (nevi) and uterine fibroids (leiomyomas).

Although most benign tumors are not life-threatening, many types of benign tumors have the potential to become cancerous (malignant) through a process known as tumor progression. For this reason and other possible negative health effects, some benign tumors are removed by surgery.

• Malignant—Malignant neoplasms are a mass of cells (tumor) that have the

ability to invade neighboring tissue or metastasize to other organs. Skin neoplasms are named after the type of skin cell from which they arise. Basal cell cancer originates from the lowest layer of the epidermis, and is the most

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common but least dangerous skin cancer. Squamous cell cancer originates from the middle layer, and is less common but more likely to spread and, if untreated, become fatal. Melanoma, which originates in the pigment-producing cells (melanocytes), is the least common, but most aggressive, most likely to spread and, if untreated, become fatal.

• Carcinoma in situ-- a cluster of malignant cells that has not yet invaded the deeper epithelial tissue or spread to other parts of the body. If untreated long enough, it can spread to other organs.

• Uncertain—Early in the diagnostic process, some neoplasms have characteristics of both benign and malignant neoplasms. Therefore, until further diagnostic tests occur, a physician may not be able to be more specific in diagnosis assignment.

• Unspecified—This classification of neoplasm is used when a neoplasm is identified, but no additional information is yet available to establish a diagnosis.

Coding for neoplasms of the skin is based on its location(s) on the body and the type of neoplasm. CAUSES OF SKIN CANCER Skin cancer is the most common cancer in the United States. According to the National Cancer Institute (NCI), over one million people in the U.S. are diagnosed with skin cancer every year. Research has led to better methods of diagnosing and treating this disease. The NCI says skin cancer is now almost 100 percent curable if found early and treated promptly. Ultraviolet (UV) radiation from the sun is the main cause of skin cancer. There are two types - UVA and UVB. Sunlamps and tanning booths which are artificial forms of UV radiation, can also cause skin cancer. People with a family history of skin cancer are generally at a higher risk of developing the disease. People with fair skin and a northern European heritage appear to be most susceptible. PHYSIOLOGY AND PATHOPHYSIOLOGY ISSUES FOR ICD-10 The introduction of ICD-10 will produce a substantial increase in specificity related to certain conditions and situations. Some of the issues include: Laterality In many cases, ICD-10 requires the physician and coder to indicate which side of the body is being treated

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When laterality is reported, “left” always means the patient’s left side and “right” always means the patient’s right-side. The diagram immediately above illustrates how “side” is defined. The medical record must indicate side, whenever possible, to facilitate appropriate code selection. When reporting melanomas and other malignant neoplasms of the skin, laterality is always required, in addition to the specific location (e.g. right upper limb, including shoulder vs. right lower limb, including hip). If a specific side is not reflected in the medical record, an “unspecified” code must be used, which is usually suboptimal when seeking payment from third party payers. Type/Location In ICD-10-CM, a dramatically higher degree of specificity is necessary in relationship to the type and location of conditions, such as abscesses, cellulitis/lymphangitis, and disorders of pigmentation. Some examples of required specificity include:

• In ICD-9-CM, carbuncles and furuncles are reported using the same code. In ICD-10-CM, distinct codes are required for each.

• In ICD-9-CM, cellulitis/acute lymphangitis of the trunk are reported with a single code. In ICD-10-CM, the distinction is made between cellulitis and lymphangitis and there are 8 separate codes available for each condition to report the exact location.

• In ICD-9-CM, there is no specific section for disorders of pigmentation. In ICD-10-CM, there is a separate section and 11 codes available to report the various disorders.

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Ulcers In ICD-9-CM, there are substantial differences in the way in which ulcers are reported, as compared to ICD-10-CM. The differences include: ICD-9-CM ICD-10-CM Laterality Not used Always required, when

appropriate Pressure ulcers General location reported,

with a secondary code used to indicate the stage.

Staging is included in the pressure ulcer codes (single code used).

Non-pressure ulcers General code used, based only on location.

Code using location is reported, which also includes the severity of the condition

• Breakdown of skin • Fat layer exposed • Necrosis of muscle • Necrosis of bone

Stage 1 ulcers are not open wounds. The skin may be painful, but it has no breaks or tears. The skin temperature is often warmer. A stage 1 ulcer can feel either firmer or softer than the area around it.

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In stage 2 ulcers, the skin breaks open or wears away, which is usually tender and painful. The ulcer expands into deeper layers of the skin. It can look like a scrape (abrasion), blister, or a shallow crater in the skin. Sometimes this stage looks like a blister filled with clear fluid. During stage 3, the ulcer becomes worse and extends into the tissue beneath the skin, forming a small crater. Fat may show in the sore, but not muscle, tendon, or bone. In stage 4, the pressure ulcer is very deep, reaching into muscle and bone and causing extensive damage. Damage to deeper tissues, tendons, and joints may occur. There are also pressure ulcers that are "unstageable," meaning that the stage is not clear. In these cases, the base of the ulcer is covered by a thick layer of other tissue and pus that may be yellow, gray, green, brown, or black. The provider cannot see the base of the sore to determine the stage.