Etiologies of FUo ■| nfection O Tuberculosis:. Disseminated Usually extrapulmonary Occurs in the lungs and significant pre-existing lung disease Pulmonary TB in AIDS is often subtle(normal chest X-rays→15-30%) a PPD(+)<50%of TB with PUO a Diagnosis often requires Bx of LN/Liver/Bone marrow Sputum smear(+)only 25% Clinic. variousEtiologies of FUO  Infection Tuberculosis: .. Disseminated  Usually extrapulmonary  Occurs in the lungs and significant pre-existing lung disease.  Pulmonary TB in AIDS is often subtle (normal chest x-rays → 15 – 30%).  PPD (+) < 50% of TB with PUO.  Diagnosis often requires Bx of LN/Liver/Bone marrow.  Sputum smear (+) only 25%  Clinic : various