Disseminated Mycobacterium tilburgii infection in a person with AIDS: A case report

Background: Mycobacterium tilburgii is a nonculturable, nontuberculous mycobacterium that occasionally causes serious infections in individuals with immune deficiencies. Owing to its nonculturable nature, its antimicrobial susceptibility has not been assessed, and the optimal treatment regimen is unclear. Herein, we report a case of disseminated M. tilburgii infection in a person with AIDS, identified using metagenomics next-generation sequencing (mNGS) and polymerase chain reaction (PCR). Case presentation: A 33-year-old man presented with a 3-month history of abdominal pain, lymphadenopathy, intermittent night hot flashes, night sweats, and weight loss. No pathogen was detected during initial routine investigations. M. tilburgii was subsequently identified in a left cervical lymph node sample using mNGS. Furthermore, M. tilburgii infection was detected in a bone marrow sample based on PCR of 16S rRNA and hsp65 gene sequencing. The person was treated with a combination of moxifloxacin, clarithromycin, ethambutol, rifabutin, and amikacin. The laboratory results improved, and the patient's symptoms resolved. Conclusion: M. tilburgii may be missed in diagnostic tests because it cannot be grown using routine culture techniques. Early diagnosis and timely and effective treatment are critical in patients with M. tilburgii infection; therefore, molecular techniques are recommended for patients with suspected M. tilburgii infection.