An 18-year-old boy presented with on and off low-grade fever for 3 months and anorexia and progressive pallor for 1 month. The fever was more in evening times as remembered by the caregivers but was not associated with chills/rigor. There were no symptoms suggestive of respiratory, cardiovascular, gastrointestinal, hepatic, or renal involvement such as cough, fast breathing, breathlessness, pain abdomen, abdominal distension, jaundice, and change in color or amount of urine output. There was no history of any drug ingestion, apart from paracetamol during these 3 months and before that. Apart from pallor, the systemic examination was otherwise normal.
Hematological parameters revealed hemoglobin of 6 g/dl, normocytic and normochromic red blood cells, leukocyte count of 2640/mul, 64% lymphocytes, platelet count of 37,500/mul, and erythrocyte sedimentation rate was 22 mm in 1st h. Peripheral smear did not show any hemoparasites or any other abnormalities. Liver and kidney function tests, autoimmune profile, serum triglyceride, and ferritin levels for hemophagocytic lymphohistiocytosis (HLH), workup for viral and parasitic causes including malaria, hepatitis B and C, Epstein-Barr virus, parvovirus, and human immunodeficiency virus (HIV) were noncontributory. Workup for atypical bacterial infections such as bartonellosis and brucellosis was also negative. Serum Vitamin B12, folate, and lactate dehydrogenase levels were normal. Although Mantoux test showed an induration of 11 mm at 48 h, Chest X-ray was normal, and ultrasound abdomen showed only a few subcentimeteric mesenteric lymph nodes. Computed tomography of neck, chest, and abdomen also did not reveal any significant abnormality.
On asking leading questions, the parents revealed paternal grandfather is taking ATT for sputum-positive pulmonary TB for the past 5 months. Subsequently, bone marrow (BM) examination was performed, which revealed a hypocellular marrow, no blast cells, with infiltration by epithelioid granulomas having central caseating necrosis. Stain for AFB and GeneXpert was negative, but in view of positive contact history and corroborative findings, the diagnosis of bone marrow TB was considered. Sarcoidosis was ruled out as serum angiotensin-converting enzyme level, and urine calcium creatinine ratio was normal. He showed favorable clinical response with slow improvement in hematological parameters (repeat Hb-9 g/dl, total leukocyte count - 5670/mul, platelet count - 152,000/mul) and resolution of pyrexia within 2 months after starting ATT. Currently, on follow up after 1 year of instituting ATT, the child has completed the course of ATT 6 months back, latest hematological parameters are all within normal limits.