PNEUMONIA : DEFINTION, CAUSES, TYPES, DIAGNOSIS, TREATMENT
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Pneumonia Clinical Approach |
Pneumonia is a clinical picture that should be the bread and butter of the undergraduate and postgraduate. There is no escaping this case, as many people present to the hospital complaining of fever, cough and sputum to be soon diagnosed as pneumonia. Here are the facts to recognize and treat pneumonia. On one hand, toddlers in pneumonia is significantly common, pneumonia in adults is equally important.
In today's blog, we are going to cover What is pneumonia, Causes, Types, Clinical features including Signs and Symptoms of pneumonia, Complications, Diagnosis, and finally the Treatment for pneumonia.
DEFINITION
Pneumonia is defined as an inflammatory consolidation of the pulmonary parenchyma caused by pyogenic organisms. Besides, infection pneumonia can also be caused by aspiration, inhalation of noxious chemicals or trauma to the chest.
CAUSES
Pneumonia can be a result of a variety of cause. The most common are;
1) Bacterial pneumonia: Most common organism is Streptococcus pneumoniae. Other organisms include Haemophilus influenza and Mycoplasma pneumoniae. An infection by Mycoplasma organism gives rise to Tuberculous Pneumonia.
2) Viral pneumonia: More common in pediatric patients. Para-influenza, RSV, rhinovirus, coronavirus and etc.
3) Fungal pneumonia: Rare but can be seen in immuno-compromised patients (AIDs, long term steroid therapy, immunosuppressant); most common organisms are aspegillus fumigatus, cryptococcus neoformans, histoplama capsulatum, histoplasma capsulatum, pneumocystic jiroveci and coccidiomycosis.
4) Parasitic pneumonia: toxoplasma gondii, strongyloides stercoralis and ascariasis.
5) Aspiration pneumonia: Usually occurs in those with stroke, myasthenia, bulbar palsies, decreased consciousness, oesophageal disease, or patients with poor dental hygiene.
6) Chemical pneumonia: Noxious chemicals are inhaled and may cause inflammation. Common chemical includes gasoline, petroleum pesticides and etc.
7)Tumors: Benign tumors or malignant tumors may lead to obstruction, narrowing of bronchus and subsequent infection.
8) Trauma: Trauma to the chest (e.g. Motor Vehicle Accident) can cause inflammation of the lung parenchyma.
TYPES
Pneumonia can be classified based on how it was acquired:
1.) Community Acquired Pneumonia:
The most common type of pneumonia, it is most of the result of an infection. It is defined as pneumonia that develops outside of the hospital/nursing care home or within 48 hours of hospital admission.
2.) Institutional-Acquired Pneumonia:
This can be further subdivided into two types Healthcare-associated pneumonia (HCAP) and nursing home-associated pneumonia.
Risk factors for Institutional Acquired Pneumonia:
- Exposure to antibiotics, chemotherapy or wound care within 30 days of current illness
- Hospitalization for 2 or days within 90 days of hospitalization
- Haemodialysis
- Residence in a nursing home or long term care facility
- Home nursing care
- Contact with close family members with multi drug resistant bacteria
3.) Nosocomial Pneumonia:
This can be subdivided into 2 categories Hospital Acquired Pneumonia (HAP) and Ventilator Acquired Pneumonia (VAP). The similarity between the two are the duration which occurs 48 hours. The difference, is how they are acquire.
HAP is acquired after 48 hours of hospital admission while VAP is acquired after endotracheal intubation. This is the result of Multi Drug Resistant bacteria that are present in the hospital setting.
On basis of affected area of lung, Pneumonia can again be classified as:
1.) Lobar pneumonia: Involves lobe of the lung in its entirety.
2.) Bronchopneumonia: Does not involve the entire lobe
CLINICAL FEATURES
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CLINICAL FEATURES OF PNEUMONIA |
HISTORY OF PNEUMONIA
- Fever that can present with chills and rigor
- Productive Cough with purulent sputum
- Dyspnoea
- Haemoptysis
- Pleuritic Pain (pain on inspiration)
PHYSICAL EXAMINATION OF PNEUMONIA
- Pyrexia (Fever)
- Cyanosis
- Tachypnoea
- Tachycardia
- Hypotension
- Diminished expansion
- Dull to percussion
- Increased tactile and vocal fremitus
- Bronchial Breathing
The severity of the illness can be quantified using the “CURB-65” scoring system.
- Confusion
- Urea greater than 7 mmol/L
- Respiratory rate equal or more than 30 breaths/min
- Blood Pressure less than 90 systolic and/or 60 diastolic
- Over the Age of 65
COMPLICATIONS
Complications of Pneumonia include the following:
- Pleural Effusion
- Empyema
- Lung abscess
- Respiratory failure
- Septicemia
- Brain abscess
- Pericarditis
- Myocarditis
- Cholestatic jaundice
DIAGNOSIS
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Chest Xray showing Pneumonia |
Following tests are done to diagnose Pneumonia, Chest x-ray and sputum being the most useful.
- Full Blood Count: white cell count is raised in bacterial pneumonia.
- Arterial Blood Gas: In severe pneumonia, hypoxia and/or hypercapnia.
- ESR: In case of tuberculous pneumonia, the range will be 80-100 mm.
- Chest X-Ray: Areas of Consolidation can be seen.
- Sputum Examination: sputum should be examined with culture and sensitivity in the case of bacterial infection. Acid Fast Bacilli smear and culture to look out for tuberculous pneumonia, Fungal Culture as the name suggest to look for spores and hyphae of fungal organisms.
- Pleural Fluid: pleural fluid is aspirated and cultured for diagnosis.
TREATMENT
Treatment is to cure the cause of Pneumonia as soon as possible followed by symptomatic relief to the patient:
- Antibiotics: Give according to sensitivity result to avoid MDR.
- Chest Physio: Patients will present with sputum, this helps relieve the symptoms by removing secretions.
- Bronchodilators: may help reduce dyspnoea.
- Hydration: Patient may be dehydrated from fever. Follow fluid resuscitation protocol.
- O2 therapy: In severe cases of pneumonia. Keep oxygen saturation above 92% to avoid respiratory distress.
- Analgesia: If patient complains of pain on inspiration, paracetamol can provide relief.
- Discharged patients should come again for follow-up after 6 months and another chest x-ray taken.
REFERENCES
1. Khajotia RR.Excellence in Clinical Case Presentation in Medicine. Melaka: Colour Box Publishing House; 2012
2. Lawson P, Chen W. Oxford Handbook of Clinical Medicine, 9th ed. New York: Oxford University Press; 2014Labels: MBBS Students, Medicine, Paediatrics