ADA: adenosine deaminase; AFB: acid fast bacilli; CD4: cluster of differentiation 4; CSF: cerebrospinal fluid; HIV: human immunodeficiency virus; LF-ULAM: lateral flow urine lipoarabinomannan; NAAT: nucleic acid amplification test; N/A: not applicable; TB: tuberculosis. The gene discussed is CD4; the disease is tuberculosis.