Pneumocystis jirovecii, formerly known as a protozoan but now classified as a fungus, causes Pneumocystis pneumonia. It was previously called P. carinii but is now known as P. jirovecii. The fungus forms rounded cysts containing multiple nuclei that can spread from the lungs of infected individuals through the air. Pneumocystis pneumonia develops when both cellular and humoral immunity are defective, allowing the organisms to multiply uncontrolled in the lungs and cause illness. Diagnosis involves examining samples from the lungs under a microscope or using PCR to detect the organism's DNA. Treatment is with the antibiotic TMP/SMX administered orally or intravenously.

1. Pneumocystis jirovecii
PRESENTED BY,
JAYAPRIYA R
BP211513
I-M.Sc Microbiology
Sacred Heart College,

2. GENERAL CHARACTERISTICS :
 Pneumocystis jirovecii, the fungus that causes Pneumocystis
pneumonia.
Till Recently P.jirovecii was thought to be protozozan but is
now considered a fungus. Pneumocystis jirovecii used to be
called
Fungus:Ascomycetes
Class: Pneumocystidomycetes
Family: Pneumocystidaceae
Species: P. jirovecii
Kingdom: Fungi

3. MORPHOLOGY:
Pneumocystis jirovecii
cysts are
 rounded and
approximately
in size, although thin-
walled cysts exist also.
 Cyst Contains
nuclei.

4. PATHOGENESIS:
PCP spreads from
Some healthy adults can carry the Pneumocystis fungus in
their and it can spread to
other people, including those with
Disease occurs when both cellular immunity and humoral
immunity are defective.
Once inhaled, the trophic form of Pneumocystis organisms

5. PATHOGENESIS:
Multiple host immune defects allow for uncontrolled
organisms and development of
illness.
 Activated alveolar macrophages are
unable to eradicate Pneumocystis organisms.
 Increased alveolar-capillary permeability is visible on
electron microscopy.

6. SYMPTOMS:
Sudden start of Fever
Dry Cough
Difficulty breathing
Chest pain
Chills
Fatigue (tiredness)
With little or No mucus.

8. LABORATORY DIAGNOSIS:
PCP is diagnosed using a sample from a
The sample is usually that is either coughed up by the
patient Sputum or collected by a procedure called
Sometimes, a small sample of is used to
diagnose PCP.

9. The patient’s sample is sent to a laboratory, usually to be
Polymerase chain reaction can also be used to detect
Pneumocystis DNA in different types of samples.
A blood test to detect (a part of the cell wall of
many different types of fungi) can also help diagnose PCP.

10.  PCP must be treated with prescription medicine. Without
treatment,
The most common form of treatment is
trimethoprim/sulfamethoxazole (TMP/SMX), which is also
known as
This medicine is given by or through a
TMP/SMX can cause side effects such as and Other
medicines are available for patients who cannot take
TMP/SMX.
or
TREATMENT: