This patient has strongly suspected pulmonary tuberculosis and will begin four-drug therapy with isoniazid, rifampin, pyrazinamide, and ethambutol. All patients starting antituberculous therapy should have baseline measurements of aminotransferases, bilirubin, alkaline phosphatase, serum creatinine, and a platelet count. Specific adverse effects of ethambutol include a retrobulbar neuritis manifesting as decreased green-red color discrimination or decreased visual acuity. Therefore, baseline testing of color discrimination and visual acuity with monthly questioning regarding any visual abnormalities is recommended for patients taking ethambutol, with monthly testing for patients taking the drug for more than 2 months, patients with kidney disease, and patients receiving more than 15 to 25 mg/kg of ethambutol. Rash and peripheral neuritis are also reported with ethambutol use. Adverse effects of isoniazid use include peripheral neuropathy, hepatitis, rash, and a lupus-like syndrome. Pyrazinamide can cause hepatitis, rash, gastrointestinal upset, and hyperuricemia. Rifampin can cause hepatitis, gastrointestinal upset, rash, and orange coloring of body fluids. All patients should be evaluated at least monthly for adherence to these medications as well as possible adverse reactions.

Baseline audiogram and vestibular testing (including Romberg testing) is recommended for patients receiving streptomycin, an aminoglycoside with adverse effects, including ototoxicity (hearing and vestibular disturbances), neurotoxicity, and nephrotoxicity. Monthly questioning regarding vestibular/auditory symptoms and monthly assessments of kidney function are recommended.

Patients with HIV who become infected with tuberculosis should have a CD4 cell count performed as part of baseline monitoring.