Pneumocystis is found in the respiratory tract of most mammals and Man. Pneumonia from this organism was extremely rare or unknown before the advent of AIDS.
When the lymphocyte count of a person with AIDS drops below 500, or especially 200, pneumocystis pneumonia is a frequent complication. Symptoms include cough, fever, rapid breathing, and shortness of breath.. The chest x-ray typically shows a “ground glass” appearance, caused by fluid inside the air sacs and throughout the lung. Treatment is usually with trimethoprim sulfa.
Immunosuppressive therapy is often given for organ transplants and auto immune diseases these days. Patients and doctors should be on the lookout for pneumocystis symptoms in this situation. Even long-term corticosteroids can produce enough immunosuppression to allow pneumocystis to invade the body.
Pneumocystis Jeroveci is the causative organism, and used to be called pneumocystis Carini. Doctors suspect this disease when an immuno-suppressed patient, especially AIDS , has a dry cough, with pneumonia and a very low oxygen concentration, more severe than expected. Fluid taken from the lung shows several organisms in little sacks or cysts.
Treatment is with sulfonamids, if they are tolerated. Cortisone must be given not the same time to prevent a severe reaction from absorption of the dead organisms. Pneumocystis is a yeast-like fungus and is also discussed under opportunistic fungal infections.
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