Respiratory tract infection

Respiratory Tract Infection

Dr. C.B.Pun

Respiratory Tract Infection.Respiratory tract infection refers to any of a number of infectious diseases involving the respiratory tract. An infection of this type is normally further classified as an upper respiratory tract infection (URTI) or a lower respiratory tract infection(LRTI). Lower respiratory infections, such as pneumonia, tend to be far more serious conditions than upper respiratory infections, such as the Respiratory Tract Infection common cold.

Upper respiratory tract infection

the upper respiratory tract is generally considered to be the airway above the glottis or vocal cords. This includes the nose, sinuses, pharynx, and larynx.

Typical infections of the upper respiratory tract include tonsillitis, pharyngitis, laryngitis, sinusitis, otitis media, certain types of influenza, and the common cold.Symptoms of URIs can include cough, sore throat, runny nose, nasal congestion, headache, low grade fever, facial pressure and sneezing.

Tonsillitis

Tonsillitis is inflammation of the tonsils most commonly caused by viral or bacterial infection. Symptoms may include sore throat and fever. When caused by a bacterium belonging to the group A streptococcus

Signs and symptoms

Common signs and symptoms include• sore throat• red, swollen tonsils• pain when swallowing• high temperature (fever)• coughing• headache• tiredness• chills• a general sense of feeling unwell (malaise)• swollen lymph nodes (glands) in the neck

Less common symptoms include:

• nausea• vomiting• furry tongue• bad breath (halitosis)• voice changes• difficulty opening the mouth (trismus)

Causes The most common cause is viral infection and

includes adenovirus, rhinovirus, influenza and It can also be caused by Epstein-Barr virus and cytomegalovirus.

Less common bacterial causes include: Staphylococcus aureus (including methicillin resistant Staphylococcus aureus or

MRSA ),Streptococcus pneumoniae, Mycoplasma pneumoniae. chlamydia pneumonia.

Diagnosis

The diagnosis of tonsillitis can be confirmed by culture of samples obtained by swabbing.

A single throat culture has a sensitivity of 90%-95% for the detection of tonsillitis.

Treatment

Treatments to reduce the discomfort from tonsillitis symptoms include:

•pain relief, anti-inflammatory, fever reducing medications (acetaminophen/paracetamol and/or ibuprofen)

•sore throat relief (warm salt water gargle, lozenges, dissolved aspirin gargle (aspirin is an anti inflammatory, do not take any other anti inflammatory drugs with this method), and iced/cold liquids)

If the tonsillitis is caused by group A streptococus, then antibiotics are useful with penicillin or amoxicillin being primary choices.Cephalosporins and macrolides are considered good alternatives to penicillin in the acute setting.

When tonsillitis is caused by a virus, the length of illness depends on which virus is involved. Usually, a complete recovery is made within one week; however, symptoms may last for up to two weeks. Chronic cases may be treated with tonsillectomy (surgical removal of tonsils) as a choice for treatment.

Pharyngitis

It is an inflammation of the throat. In most cases it is quite painful, and is the most common cause of a

sore throat. Like many types of inflammation, pharyngitis can be acute –

characterized by a rapid onset and typically a relatively short course – or chronic

can be accompanied by a cough or fever, for example, if caused by a systemic infection.

Most acute cases are caused by viral infections (40–80%), with the remainder caused by bacterial infections, fungal infections, or irritants such as pollutants or chemical substances. Treatment of viral causes are mainly symptomatic while bacterial or fungal causes may be amenable to antibiotics and anti-fungal respectively.

Pharyngitis

Cause

Viral Adenovirus – the most common of the viral causes. Orthomyxoviridae which cause influenza Herpes simplex virus can cause multiple mouth ulcers. Measles

Bacterial

A number of different bacteria can infect the human throat. The most common is Group A streptococcus, however others include Corynebacterium diphtheriae, Neisseria gonorrhoeae, Chlamydophila pneumoniae, and Mycoplasma pneumoniae.

Diagnostic approach

It is hard to differentiate a viral and a bacterial cause of a sore throat based on symptoms alone. Thus often a throat swab is done to rule out a bacterial cause.

Management

The majority of time treatment is symptomatic. Specific treatments are effective for bacterial, fungal, and herpes simplex infections.

Analgesics such as NSAIDs and acetaminophen can help reduce the pain associated with a sore throat.

Antibiotics are useful if a bacterial infection is the cause of the sore throat. For viral infections, antibiotics have no effect.

Oral analgesic solutions.

Laryngitis

Laryngitis is an inflammation of the larynx. It causes hoarse voice or temporary complete loss of the voice because of irritation to the vocal folds (vocal cords). Dysphonia is the medical term for a vocal disorder, of which laryngitis is one cause.

Laryngitis is categorized as acute if it lasts less than a few days. Otherwise it is categorized as chronic, and may last over three weeks.

Laryngitis

Causes

Noninfectious causes

• Acid reflux disease, resulting in laryngitis gastrica.• Allergies.• Excessive coughing, smoking, or alcohol consumption.• Inflammation due to overuse of the vocal cords• Prolonged use of inhaled corticosteroids for asthma treatment.• Thermal or chemical burns.• Laryngeal trauma, including iatrogenic one caused by endotracheal intubation.

Infectious causes

•Viral infections can be caused by rhinovirus, influenza virus, coronavirus..

•Bacterial infections can be caused by group A streptococcus, C. diphtheriae, M.catarrhalis, and M.tuberculosis. Bacterial infections usually follow pre-existing viral infection.

•Fungal infections can be caused by Histoplasma, Blastomyces, Candida.

Symptoms

• Dysphonia (hoarseness) or aphonia (inability to speak)• Dry, sore, burning throat• Coughing• Dysphagia (difficulty in swallowing)• Sensation of swelling in the area of the larynx• Cold or flu-like symptoms • Swollen lymph nodes in the throat, chest, or face• Fever• Dyspnea (difficulty in breathing)• Increased production of saliva

Treatment General measures: Voice rest is important

If laryngitis is due to gastroesophageal reflux, an H2-inhibitor (such as ranitidine) or proton-pump inhibitor (such as omeprazole) is used to reduce gastric acid secretions

In viral laryngitis, drinking sufficient fluids is helpful.

If laryngitis is due to a bacterial or fungal infection, appropriate antibiotic or antifungal therapy is given.

Sinusitis

Sinusitis is inflammation of the paranasal sinuses, which may be due to infection, allergy, or autoimmune issues. Most cases are due to a viral infection and resolve over the course of 10 days.

Sinusitis

Classification•acute sinusitis — a new infection that may last up to four weeks.

•subacute sinusitis — an infection that lasts between four and 12 weeks, and represents a transition between acute and chronic infection;

•chronic sinusitis — when the signs and symptoms last for more than 12 weeks.

Signs and symptoms

Headache/facial pain or pressure of a dull, constant, or aching sort over the affected sinuses is common with both acute and chronic stages of sinusitis. This pain is typically localized to the involved sinus and may worsen when the affected person bends over or when lying down. Pain often starts on one side of the head and progresses to both sides.

Sinus infections can also cause inner ear problems due to the congestion of the nasal passages. This can be demonstrated by dizziness, "a pressurized or heavy head", or vibrating sensations in the head. Other symptoms of sinusitis include bad breath and Post-nasal drip.

Recent studies suggest that up to 90% of "sinus headaches" are actually migraines.

due to the autonomic nerve stimulation that can also cause tearing (lacrimation) and a runny nose (rhinorrhea).

cause:

Factors which may: predispose someone to developing sinusitis include allergies

Diagnosis

Acute Bacterial and viral acute sinusitis are difficult to distinguish. However, if symptoms last less than 10 days, it is generally considered viral sinusitis. When symptoms last more than 10 days, it is considered bacterial sinusitis. At this point 30% to 50% of cases are bacterial. Chronic For sinusitis lasting more than 12 weeks

Antibiotics

The vast majority of cases of sinusitis are caused by viruses and will therefore resolve without antibiotics.However, if symptoms do not resolve within 10 days, amoxicillin is a reasonable antibiotic to use first for treatment with amoxicillin/clavulanate being indicated when the person's symptoms do not improve after 7 days on amoxicillin alone.Antibiotics are specifically not recommended in those with mild / moderate disease during the first week of infection

Common cold

The common cold (also known as nasopharyngitis, rhinopharyngitis) is a viral infectious disease of the upper respiratory tract which affects primarily the nose. Symptoms include coughing, sore throat, runny nose, sneezing, and fever which usually resolve in seven to ten days, with some symptoms lasting up to three weeks.

the cause of the common cold; the rhinoviruses are the most common.

Signs and symptoms

The typical symptoms of a cold include cough, runny nose, nasal congestion and a sore throat, sometimes accompanied by muscle ache, fatigue, headache, and loss of appetite.

Cause

ViralThe common cold is a viral infection of the upper respiratory tract. The most commonly implicated virus is a rhinovirus (30–80%), a type of picornavirus with 99 known serotypes. Others include: coronavirus (10–15%), influenza viruses (10-15%) adenoviruses (5%), enteroviruses, and metapneumovirus.

Transmission

The common cold virus is typically transmitted via airborne droplets (aerosols), direct contact with infected nasal secretions, or fomites (contaminated objects).Which of these routes is of primary importance has not been determined, however hand-to-hand and hand-to-surface-to-hand contact seems of more importance than transmission via aerosols.

Diagnosis The distinction between different viral upper respiratory tract

infections is loosely based on the location of symptoms with the common cold affecting primarily the nose, pharyngitis the throat, and bronchitis the lungs.

Self-diagnosis is frequent.

Prevention The only possibly useful ways to reduce the spread of cold viruses

are physical measures such as hand washing and face masks; in the healthcare environment, gowns and disposable gloves are also used.

Management

Symptomatic

Treatments that help alleviate symptoms include simple analgesics and antipyretics such as ibuprofen and acetaminophen/paracetamol.

In adults the symptoms of a runny nose can be reduced by first-generation antihistamines; however, these sometimes have adverse effects such as drowsiness

Antibiotics and antivirals

Antibiotics have no effect against viral infections and thus have no effect against the viruses that cause the common cold

Lower respiratory tract infection

Bronchitis

Pneumonia

Bronchitis Bronchitis is an inflammation of the mucous

membranes of the bronchi (the larger and medium-sized airways that carry airflow from the trachea into the more distal parts of the lung parenchyma).

Cough, a common symptom of acute bronchitis, develops in an attempt to expel the excess mucus from the lungs.

Other common symptoms of acute bronchitis include: sore throat, shortness of breath, fatigue, runny nose, nasal congestion, low-grade fever, pleurisy, malaise, and the production of sputum.

Bronchitis may be diagnosed by a physician during a thorough physical examination. Due to the nonspecific signs and symptoms exhibited by individuals with bronchitis, diagnostic tests such as a chest x-ray to rule out pneumonia, a sputum culture to rule out whooping cough or other bacterial respiratory infections, or a pulmonary function test to rule out asthma or emphysema may be used.

Treatment for acute bronchitis is primarily symptomatic. Non-steroidal anti-inflammatory drugs (NSAIDs) may be used to treat fever and sore throat. Even with no treatment, most cases of acute bronchitis resolve quickly.

Chronic bronchitis Chronic bronchitis, a type of chronic obstructive pulmonary

disease, is defined by a productive cough that lasts greater than three months each year for at least two years in the absence of other underlying disease. Bacterial bronchitis is defined as a chronic productive cough with a positive bronchoalveolar lavage that resolves with antibiotics.

Symptoms of chronic bronchitis may include wheezing and shortness of breath, especially upon exertion and low oxygen saturations.The cough is often worse soon after awakening and the sputum produced may have a yellow or green color and may be streaked with specks of blood.

Chronic bronchitis is treated symptomatically

Pneumonia Pneumonia is an inflammatory condition of the lung—

affecting primarily the microscopic air sacs known as alveoli. It is usually caused by infection with viruses or bacteria and less commonly other microorganisms,and other conditions such as autoimmune diseases.

  Typical symptoms include a cough, chest pain, fever, and

difficulty breathing. Diagnostic tools include x-rays and culture of the sputum. Vaccines to prevent certain types of pneumonia are available. Treatment depends on the underlying cause. Bacterial pneumonia is treated with antibiotics. If the pneumonia is severe, the affected person is generally admitted to hospital.

Thank you….