Clinical features of rare disseminated Mycobacterium colombiense infection in nine patients who are HIV-negative in Guangxi, China.

Objectives: Localized or disseminated infection caused by different nontuberculous mycobacteria (NTM) species has been increasingly reported in recent years, but reports of Mycobacterium colombiense infection are extremely rare. Herein, we analyzed the clinical features of patients with disseminated M. colombiense infection.

Methods: Patients diagnosed with disseminated M. colombiense infection between February 4, 2016 and August 25, 2021 at the First Affiliated Hospital of Guangxi Medical University were retrospectively analyzed.

Results: NTM infection was diagnosed in 248 HIV-negative patients. Of these, nine patients with disseminated M. colombiense infection were enrolled. Five of these patients were positive for anti-interferon-γ autoantibodies. The lung, lymph nodes, bones, and joints were the most commonly involved organs. Anemia, fever, lymphadenopathy, cough and expectoration, and ostealgia were the most common symptoms. The levels of white blood cells and neutrophils were increased in eight patients. M. colombiense was detected by both metagenomic next-generation sequencing (mNGS) and culture in four patients and only by mNGS in the remaining five patients. All patients received combination anti-NTM therapy; five underwent surgery. The condition of eight patients improved, and one died during the treatment.

Conclusion: Patients infected with M. colombiense can present as disseminated infections, easily involving multiple organs, such as the lung, lymph nodes, bone, and joints, with fever, lymphadenopathy, and increased white blood cell and neutrophil counts. mNGS plays a crucial role in the early diagnosis of M. colombiense infection. Once diagnosed, timely and effective anti-NTM therapy, combined with local surgery if necessary, can improve the prognosis of patients with this condition.