Multifocal pneumonia is a type of pneumonia that affects more than one area of the lungs and causes similar symptoms to other types of pneumonia. It can either affect one (unilateral) or both (bilateral) of the lungs at one time and can be caused by the same pathogens (bacteria, viruses, and fungi) that cause other types of pneumonia. What makes multifocal pneumonia different is how the illness presents in the lungs, with more than one site of infection and inflammation. Bacteria such as Streptococcus pneumoniae or Legionella pneumophila, and fungi such as Pneumocystis pneumonia, Coccidioidomycosis, or Cryptococcus are all capable of causing multifocal pneumonia.

Multifocal pneumonia can be diagnosed through chest radiography, which may show airspace and interstitial opacities in multiple areas of the lungs. Symptoms of multifocal pneumonia include fever, cough, wheezing, and dyspnea. If diagnosed early, multifocal pneumonia can be treated with a relatively short recovery period. However, this type of pneumonia tends to result in a more severe infection that may require hospitalization.

Multifocal pneumonia can be mistaken for other respiratory illnesses, such as COVID-19 interstitial pneumonia, which is a novel acute respiratory illness caused by SARS-CoV-2 infection. The treatment options for multifocal pneumonia include the removal of offending agents and steroids in severe cases.