A 5-month-old boy presented with fever, cough, and tachypnea that he had had for 1 month. There also was a history of poor weight gain for 2 months. The child was born full-term at a private hospital, and the mother's antenatal course was uneventful. There was no postnatal history of bleeding, jaundice, diarrhea, poor feeding, vomiting, or seizures. There was no family history of tuberculosis.
The physical examination findings included tachypnea, tachycardia, pallor, and fever. Arterial oxygen saturation was 92% on room air and improved to 98% after starting supplemental oxygen therapy. There were multiple variable-sized ulcers with a necrotic base over the trunk and right forearm.
Chest examination revealed extensive bilateral crepitations, but air entry was normal. On abdominal examination, the liver was palpable 6 cm below the costal margin, and the spleen could be palpated 2 cm below the costal margin. The results of the remainder of the systemic examination and ophthalmological examination were normal.
Tests showed a hemoglobin level of 8 g/dL; a total leukocyte count of 12,000/[micro]L, with 80% lymphocytes; a platelet count of 1,000,000/[micro]L; and an elevated erythrocyte sedimentation rate (40 mm/h). Serum biochemistry profile findings showed elevated oxaloacetate and aspartate transaminase levels (200 U/L [normal, less than 50 U/L] and 250 U/L [normal, less than 50 U/L], respectively). The TORCH profile (toxoplasmosis, rubella, cytomegalovirus infection, and herpesvirus infection) findings were negative except for an elevated IgG antibody level against cytomegalovirus.
The patient's chest radiograph is shown in the Figure.
What is the likely diagnosis?
The patient's chest radiograph showed bilateral, diffuse, tiny, round shadows ranging from 1 to 2 mm in size. Three consecutive early-morning gastric aspirate samples were negative for Mycobacterium tuberculosis, and the tuberculin test result was nonreactive. A biopsy specimen from the edge of a skin lesion showed epithelioid cell granulomas with Langerhans giant cells and central caseation necrosis. A diagnosis of miliary tuberculosis was made. A 4-drug antituberculosis regimen was started (isoniazid, 5 mg/kg; rifampicin, 10 mg/kg; pyrazinamide, 30 mg/kg; and ethambutol 15 mg/kg). (1) There was significant improvement in both skin and pulmonary lesions, and the patient was discharged after 3 weeks of hospitalization.
Miliary tuberculosis arises as a result of widespread lymphohematogenous dissemination of tubercle bacilli. The lesions are small (1 to 2 mm) foci of yellow-white consolidation scattered...