There are many types of Pneumonia and you may observe your doctor using various terms for describing pneumonia like community acquired Pneumonia, walking Pneumonia, etc. The classification of Pneumonia is done for the easy management of the disease.

Let’s see various ways of classifying Pneumonia.

On the basis of location acquired

Community-acquired pneumonia (CAP): When a person gets infected with pneumonia and he/she has not been hospitalized recently, then it is called as Community-acquired pneumonia.

It is regarded as most common type of pneumonia. The CAP is caused by Streptococcus pneumonia (Bacterium), viruses, atypical bacteria, Gram-negative bacteria and Haemophilus influenza.

Walking Pneumonia: The less severe form of community-acquired pneumonia is called as “Walking pneumonia”.  Here, the individual does not need any hospitalization and he/she may continue to walk due to less severe symptoms.

Walking pneumonia is caused by the Mycoplasma pneumonia (atypical bacterium).

Hospital-acquired (HAP/Nosocomial pneumonia): As the name suggests, this type of pneumonia is acquired by the individuals during or after hospitalization due to any other illness or procedure. The symptoms of Hospital-acquired Pneumonia develop at least 72 hrs after admission.

The causes and treatment of HAP are different from CAP. It is caused by Hospital-acquired microorganisms such as Pseudomonas, Enterobacter, MRSA, and Serratia. It is more deadly than CAP.

On the basis of area of lung affected

Lobar pneumonia: It involves infection in single lobe, or one section of a lung. It is caused by Streptococcus pneumoniae  or Klebsiella pneumonia.

Multilobar pneumonia: It involves infection in more than one lobe of lungs. It is considered to be more severe form of pneumonia where lungs are affected in patches around the bronchi or bronchioles.

Interstitial pneumonia: It involves infection in the regions present between the alveoli. It is caused by viruses or atypical bacteria.

On the basis of cause of Pneumonia

Aspiration pneumonia: It is caused by aspirating foreign objects that leads to pneumonia. These objects may contain anaerobic bacteria or contribute to other causes of pneumonia.

The aspiring objects include oral or gastric contents during eating, or after vomiting/reflux. It usually affects patients in hospitals.

Eosinophilic pneumonia: It is caused by the trigger of eosinophils (WBC) in the lungs as an immune response to infection or other environmental factors.

Chemical pneumonia: It is caused by chemical toxicants like pesticides that reach the lungs via inhalation or skin contact. The lipoid Pneumonia results from the presence of toxic oil in the lungs.

Bronchiolitis obliterans organizing pneumonia (COP/BOOP): It is caused by inflammation of the small airways present in the lungs.

Dust pneumonia: It is caused due to extreme exposure to dust that settles into the lungs alveoli.

Necrotizing pneumonia: It is caused by anaerobic bacteria and results in significant necrosis of lung cells, and lung abscess.

Opportunistic pneumonia: It occurs in the individuals with weakened immune system due to AIDS and strong chemotherapy. It is caused by cytomegalovirus, Mycobacterium avium-intracellulare and infectious agents.

Double pneumonia: It refers to acute lung injury (ALI) or acute respiratory distress syndrome (ARDS).

Severe acute respiratory syndrome: It is caused by the SARS coronavirus and it is highly contagious in nature.