One of the most common and prevalent respiratory diseases existing in this world is pneumonia. Around 450 million cases throughout the world and around 10 million cases per year in India are affected due to pneumonia.

Pneumonia is an inflammatory disease affecting the entire lungs ranging from the airways to the parenchyma to the alveoli. There are different types of pneumonia based on different criteria. The first types include community-acquired pneumonia (CAP), hospital-acquired (HAP), and ventilator-acquired (VAP), now some have combined as healthcare-associated (HCAP).

The second set is based on anatomy. Bronchopneumonia is seen as patches over the bronchi. Lobar pneumonia is seen in the single or multiple lobes and interstitial pneumonia is in-between gaps and spaces.

The next set is based on etiology. It is classified as primary, secondary, and suppurative (necrosis is involved). The last set is based on the microorganism involved. It can be viral, bacterial, or fungal.

The main cause of pneumonia is microorganisms. The common virus is influenza, corona, and adeno types. The common bacteria are S.pneumoniae, H,influenzae. Some common fungi are candida, aspergillus, and mucor.

The disease is mostly due to the proliferation of microorganisms mostly in the lower respiratory tract. This is maybe from the infected persons either through direct or indirect contact, also from the environment.

So they occupy spaces and gaps present in the respiratory system. Since it is a foreign substance, the immune system is triggered and the process of inflammation takes place. These immune cells arrive at the target site and start to phagocytize them. In this process, the immune cells release certain chemical mediators.

This results in some prominent symptoms like fever and body chills. Also, the dead cells and immune cells are present in the gaps throughout the respiratory system which is seen clearly as white spots in X-ray. These substances block the CO2 leave out of the alveoli and the O2 to enter the alveoli hence obstructing the process of respiration.

The characteristic feature seen in pneumonia is the alveoli and air sacs filled with inflammatory cells and cell debris. This can occur due to some faults/defects in the lung immune defense mechanisms. Some are loss of cough reflex, defect in natural immunity, congestion, injury to mucus, and ciliary hairs.

Some of the symptoms seen in pneumonia are mentioned below.

  • Headache
  • Low blood pressure
  • High fever & chills
  • Fatigue
  • Joint pain
  • Vomiting
  • Cough and sputum

Around 90% frequency for fatigue, 70-90% for cough, and 75% for fever. Blood tests for estimating the count of individual immune cells (CBC- complete blood count), chest X-ray, sputum testing, pulse oximetry, bronchoscopy, and lung biopsy are some of the detection methodologies for pneumonia.

Stopping the habit of smoking, getting vaccines, maintaining a good diet and regular exercise are some preventive methods that can be followed. It is better to avoid overcrowded places for safety.

Antibiotics, analgesics, and rest are some of the basic level treatments. Neuraminidase inhibitors can be used for viral pneumonia. There are some other drugs like amantadine, doxycycline, etc. for the viral type of pneumonia.


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