A person having CD-4 count of 200 presents with difficulty of breathing. Most probabl diagnosis is?

ANSWER: (D) Pneumocystis cariniREF: Harrisons 17th ed chapter 182, CURRENT Medical Diagnosis & Treatment Chapter 31. HIV Infection & AIDSThe host factors that predispose to the development of Pneumocystis pneumonia (PcP) include defects in cellular and humoral immunity. The risk of PcP among HIV-infected patients rises markedly when circulating CD4+ T cell counts fall below 200/uL.Pneumocystis pneumonia is the most common opportunistic infection associated with AIDS. Pneumocystis pneumonia maybe difficult to diagnose because the symptoms--fever, cough, and shortness of breath--are nonspecific.Other persons at risk for PcP are patients receiving immunosuppressive agents (particularly glucocorticoids) for cancer and organ transplantation; those receiving biologic agents such as infliximab and etanercept for rheumatoid arthritis and inflammatory bowel disease; children with primary immunodeficiency diseases; and premature malnourished infants.