A Case of Miliary Tuberculosis Complicated by Thyroid Involvement: Managing Rifampicin-Induced Thrombocytopenia With Rifabutin

This case report presents an unusual occurrence of miliary tuberculosis with thyroid tuberculosis in a 75year-old male patient, who successfully completed the treatment with rifabutin after rifampicin-induced thrombocytopenia. The patient has been suffering from diabetes mellitus and chronic heart failure, and had coronavirus disease of 2019 (COVID-19) just before being diagnosed with miliary tuberculosis. The patient had not been prescribed immunosuppressants and steroids. Chest computed tomography (CT) scans revealed multiple tiny nodules diffusely and equally distributed in bilateral lung fields. Subsequently, polymerase chain reaction (PCR) techniques on the urine samples and culture of sputum demonstrated positivity for Mycobacterium tuberculosis. Thus, we conclusively identified miliary tuberculosis and initiated treatment using anti-tuberculosis drugs. During treatment, the patient developed thyroid tuberculosis, resulting in an enlarged thyroid and hoarseness, but these symptoms improved with continued use of the anti-tuberculosis drugs. Moreover, regarding treatment, the rifabutin dosage was completed after changing drugs due to rifampicin-induced thrombocytopenia. Notably, miliary tuberculosis is rarely complicated by thyroid tuberculosis as a paradoxical reaction, and the substitution of rifabutin for rifampicin-induced thrombocytopenia is not fully studied. We present this case alongside relevant prior data for comprehensive clinical insight.