Mycobacterium sherrisii Lung Infection in a Brazilian Patient with Silicosis and a History of Pulmonary Tuberculosis

Abstract EN

Nontuberculous mycobacteria (NTM) diseases became relevant with the emergence and spread of HIV and are also related to lung infection in non-HIV individuals with structural lung diseases.

Mycobacterium sherrisii is a NTM first characterized in 2004.

Only a few cases have been reported.

The aim of this case report is to describe the first detailed case of infection with M.

sherrisii in a patient with silicosis and history of pulmonary tuberculosis.

A 50-year-old HIV-negative white male, previous smoker, with silicosis and a history of treated pulmonary tuberculosis developed a worsening of cough and expectoration pattern, and two sputum samples were positive for acid-fast bacilli.

Presumptive treatment for pulmonary tuberculosis was initiated with rifampin, isoniazid, pyrazinamide, and ethambutol, but, at month 5 of treatment, despite correct medication intake and slight improvement of symptoms, sputum bacilloscopy remained positive.

Sputum cultures were positive Mycobacterium sherrisii.

Treatment regimen was altered to streptomycin (for 2 months), ethambutol, clarithromycin, rifabutin, and trimethoprim-sulfamethoxazole.

M.

sherrisii should be considered a possible etiological agent of lung infections in patients with pneumoconiosis and history of tuberculosis.