Diabetes Mellitus Tom Salter F1 Warwick Hospital
Dec 26, 2015
Clinical Scenario
This is Mr Balls he has presented to his GP feeling tired for 3 months...
What are you going to ask?▫Follow a Hx taking pattern that’s
comfortable▫Narrow down to a system▫Have about 5 set questions in mind▫R/O serious pathology▫Don’t forget social and ICE
Clinical Scenario
•52 years old lethargic & tired 3/12•thirsty & drinking more than normal for
2/52•no other significant symptoms
•Hypertension on Ramipril only•No known allergies•Works as librarian, drinks socially, non-
smoker
Clinical Scenario
What do you think is wrong with the patient?
What would you like to examine?
O/E:•Obese (BMI 32)•Systems examinations otherwise
unremarkable
Clinical Scenario
•What are your differentials and why?▫Diabetes Mellitus▫Chronic kidney disease▫Diabetes insipidus▫Thyroid disease (Hypothyroidism)
Clinical Scenario
Investigations• Bedside
▫ Urine dipstick (glucose and ketones), BM, ECG
• Simple▫ Glucose, FBC (?anaemia), U+Es (?CKD), LFTs
(fatty liver, albumin), TFT,▫ Urine MC&S, albumin and ?PCR (?CKD)
• Radiological▫ ?CXR, ?USS Kidney
• Special tests▫ ?Fluid deprivation test
Clinical Scenario
ManagementRemember the blurb... “Managed in an
MDT approach...”•GP, Practice nurse, district nurses, OTs
dietician, retinal screening service, MDT diabetic foot clinic, consultant.
•Have a rough idea what each member does!
Clinical Scenario• Conservative
▫Smoking cessation – help and advice▫Lifestyle – weight loss, low GI diet, exercise▫Foot care▫Eye checks
• Medical▫Oral/Tablet control▫Insulin▫Control BP, cholesterol and other risk factors
• Surgical▫Islet cell transplants▫Rx of Complications e.g. amputation
Diabetes Medical Management
Metformin:
Mode of actionSuppresses hepatic gluconeogenesisIncreases insulin sensitivity
EffectsReduces diabetic complications,Reduces serum levels of LDL and TriglyceridesParticularly important in overweight ptsGI side effects, CI if eGFR <30ml (caution if <45)
Diabetes Medical Management
Sulfonylureas:
Mode of actionIncrease insulin secretion by Beta cells Need underlying insulin production
EffectsReduce circulating glucose (risk of hypos)Generally avoided if overweightIncreased risk of hypos if renal impairment
Diabetes Medical Management
DPP-4 inhibitors:
Mode of actionReduce circulating glucagon levels
Effects↑insulin secretion↓gastric emptying ↓blood glucoseContinue only if >0.5% ↓ in HbA1c
Diabetes Medical Management
Thiazolidinediones (glitazones):
Mode of actionActivates nuclear receptors called PPARs effecting
gene transcription
EffectsDecreased insulin resistanceIncreased free fatty acid & glucose metabolismWeight gain (↑ appetite)Pioglitazone only now (Rosi. ↑ CHD and MIs)
Diabetes Medical ManagementInsulinNICE recommends (3).. Cont. Metformin &
Sulfonylurea
1st: Intermediate NPH (porcine) insulin ON or BDOr long-acting OD if difficulty injecting
2nd: Biphasic BDparticularly if HbA1c >9% or problem with hypos
3rd: Add mealtime boluses as appropriate or consider switch to basal bolus or add thiazolidenedione
Insulin in Type 1
•How does the insulin Mx differ?▫Loss of intrinsic insulin secretion – Basal-
bolus insulin or S/C pumps needed
▫Usually a younger presentation▫S/C pumps may allow a more normal daily
routine▫Pumps require good compliance
Diagnosis Criteria
•What are the diagnostic criteria for diabetes?▫Fasting Glucose level >7.0 mmol/L▫Random Glucose level >11.1 mmol/L
▫One reading if symptomatic or two if asymptomatic
▫Also now HbA1c of 48 mmol/mol (6.5%) can be used for diagnosing diabetes (<6.5% does NOT exclude the diagnosis)
Diagnosis Criteria
•Impaired Glucose Tolerance▫7.8 mmol/L - 11.0 mmol/L▫2 hours post 75g oral glucose tolerance
test▫Greater risk of CVD and DM than IFT
•Impaired Fasting Tolerance▫6.1 mmol/L - 6.9 mmol/L ▫Fasting serum glucose
Prognosis
•75% of those with T2DM will die of heart disease
•15% of a CVA•The mortality rate from CVD is 5x higher
in those with DM (1)
•Over 60% of T1DM patients will NOT suffer serious complications. Especially if no complications by 10- 20 years post-diagnosis (5)
Complications of Diabetes
•Cardiovascular:▫Ischaemic heart disease, Cerebrovascular
disease, Peripheral vascular disease
•Renal:▫Diabetic nephropathy caused by
hyperfiltration of glucose and atheromatous changes to the blood vessels of the kidneys
Complications of Diabetes
•Neuropathic:▫Neuropathy of any nerve!▫Autonomic (GU, GI, postural hypotension)▫peripheral sensorimotor e.g glove and
stocking▫mononuritis incl. CNs▫Charcot’s foot, diabetic ulcers▫PAIN
Complications of Diabetes
• Retinopathy:▫Background
▫Pre-proliferative
▫Proliferative
• Maculopathy:
Acute complicationsHONK
▫a hyperosmolor hyperglycaemic non-ketotic state
▫T2DM
▫Usually as a result of dehydration and illness▫Inability to take diabetic medication
▫Symptoms weakness, cramps, visual impairment, confusion seizures +/- nausia & vomiting (less than DKA)
Acute complicationsHONKManagement:
▫A-E approach▫Fluid resuscitation with normal saline▫Electrolyte replacement esp. potassium▫Insulin (aiming for SLOW reduction of
serum glucose, approx 3mmol/hr)▫Senior guidance for insulin sliding scale▫VTE prophylaxis
Acute complications
DKA▫Ketonaemia (>3 mmol/L), or ketonuria (>2+)▫Bicarbonate <15 mmol/L or venous pH <7.3▫Blood glucose >11 mmol/L or known DM (not
a good indicator of severity)
▫Caused by infections, non-compliance, acute illnesses (e.g. PEs, thyroid disease etc), CVD/MI
Acute complicationsDKASymptoms:
polydipsia, polyuria, nausea & vomiting, abdominal pain
Management:Correct dehydration with IV crystaloidsReduce glucose 3mmol/L/hourRegularly monitor potassium (ECG)Do not routinely give bicarbonate or phosphateTreat the underlying illnessContinue to monitor fluid balance & electrolytes 1-2
hourly
Summary
1. Diagnosis >7.0mmol/L (fasting) >11.1mmol/L (random)
2. Minimise risk factors and maintain tight control
3. Diabetes complications: Heart, Kidneys, Eyes & Nerves PLUS DKA in T1DM, HONK in T2DM
References
1. http://www.patient.co.uk/doctor/diabetes-mellitus2. http://www.patient.co.uk/doctor/management-of-type-2-di
abetes3. http://bit.ly/GIVIAW (NICE)4. http://bit.ly/GKfqM1 (NICE)5. http://emedicine.medscape.com/article/117739-overview