Pneumocystis infection

Last updated: Saturday, 22, January, 2011
PresentationAppropriate Tests


Diagnosis is most reliably made by bronchial lavage with microscopy (special stains) and cytological examination.

PCR is available in some laboratories.

Infection occurs in the presence of Immunodeficiency, especially

  • Post-transplant immunosuppression
  • Corticosteroids
  • Severe protein malnutrition
  • AIDS
See also Infection (increased susceptibility)


Extrapulmonary pneumocystis infection can occur in AIDS, but is rare.

It is usually seen in patients with pneumocystis pneumonia who have not been receiving prophylactic cotrimoxazole.

Biopsy or FNAB (special stains) of involved tissue, eg, lymph node, is usually diagnostic.