Pneumocystis Carani

1. Pneumocystis carinii
Pneumonia
 Pneumocystis carinii pneumonia (PCP)
is an opportunistic infection that occurs in
immunosuppressed populations, primarily
patients with advanced human
immunodeficiency virus infection.

2. The classic presentation of
nonproductive cough, shortness of
breath, fever, bilateral interstitial
infiltrates and hypoxemia does
not always appear

3.  Before the epidemic of acquired
immunodeficiency syndrome (AIDS)
in the early 1980s,

4. Pneumocystis carinii pneumonia
(PCP) was a rare infection that
occurred in immunosuppressed
patients with protein malnutrition or
acute lymphocytic leukemia, or in
patients receiving corticosteroid
therapy.

6. Risk Factors and Clinical
Presentation
Defective T-cell immunity is the
primary risk factor for PCP.
 Associated clinical signs are well
defined in HIV infection and
reflect the degree of CD4+ cell
depletion

7. Physical findings are also
nonspecific.
 fine dry rales or may be
unremarkable.
In 2 to 6 percent of cases, PCP
may present with a spontaneous
pneumothorax.

8. Extrapulmonary pneumocystosis
occurs rarely, involving organs
such as the heart, skin, spleen,
thyroid or eyes.

9. The chest film typically shows
diffuse interstitial infiltrates but
can be normal in at least one
third of cases.

10. Less commonly, lobar infiltrates,
effusions or cavitary lesions mimic
other pulmonary processes.

11. Many other diseases may have a
similar presentation, including
mycobacterial, fungal, viral or
bacterial pneumonias, heart
failure, Kaposi's sarcoma and
pulmonary emboli.

12. Diagnosis
 P. carinii cannot be routinely cultured
and is identified by stains
demonstrating the cyst wall or the
trophozoite.
 Before the emergence of AIDS, PCP
was diagnosed by open lung biopsy.

13. Less invasive procedures-sputum
induction and bronchoalveolar
lavageare now the methods of
choice

14. Periodic acid-Schiff and
Papanicolou stains have been
used to display the characteristic
honeycombed froth associated
with P. carinii

15. Papanicolou staining
 It uses a combination of
haematoxylin, Orange G, eosin Y,
Light Green SF yellowish, and
sometimes Bismarck Brown Y.

16. PAS staining
 is a staining method used to etect
glycogen in tissues

17. The reaction of periodic acid
selectively oxidizes the glucose
residues, creates aldehydes that react
with the Schiff reagent and creates a
purple-magenta color

18. Solutions and Reagents:
0.5% Periodic Acid Solution:
 Periodic acid 0.5 g
 Distilled water 100 ml