TY - CHAP M1 - Book, Section TI - Pneumocystis A1 - Raffanti, Stephen P. A1 - Person, Anna K. A2 - Knoop, Kevin J. A2 - Stack, Lawrence B. A2 - Storrow, Alan B. A2 - Thurman, R. Jason PY - 2021 T2 - The Atlas of Emergency Medicine, 5e AB - Pneumocystis jirovecii (formerly carinii) pneumonia (PJP) is the most common opportunistic infection in HIV-infected patients. Clinical suspicion for PJP pneumonia in any HIV patient presenting with complaints of dyspnea and nonproductive cough should remain high, especially in those with CD4 counts <200 cells/mm3 who are not on appropriate PJP prophylaxis. Presentations can be indolent, acute, or subacute, with associated symptoms including fever, fatigue, anorexia, weight loss, and chest pain. The complete blood count is usually normal except for lymphopenia, whereas serum lactate dehydrogenase (LDH) is often elevated. Arterial blood gases (ABGs) most often reveal a respiratory alkalosis, PO2 of 70 mm Hg or less, and an increased A-a gradient of 35 mm Hg or more. Radiographic chest findings are variable with diffuse interstitial alveolar infiltrates being common. Patients may have normal oxygen saturation levels at rest, but with ambulation, they often have a rapid desaturation. SN - PB - McGraw-Hill CY - New York, NY Y2 - 2024/03/29 UR - accessemergencymedicine.mhmedical.com/content.aspx?aid=1181057377 ER -