Q. A 3-year-old boy has had a cough for 20 days, fever (100-101) once a day for 20 days, and his weight is 10 kg. Residing near a TB clinic. Montoux neg, Hb-9.5, ESR-17, TLC-5000, lypmpho 74 percent.USG abdomen normal, MP neg, widal neg, urine-NAD cxr mild rt hilar prominence, no lymphadenopathy. What should be done to rule out tuberculosis? How should it be approached? The fever is not responding to any antibiotics.