A Case of Polyserositis with Pericarditis Caused by

The incidence of diseases and deaths caused by non-tuberculous mycobacteria (NTM) has been increasing globally. However, the broad and nonspecific clinical manifestations of NTM infections make diagnosis challenging, compounded by the difficulty in isolating NTM organisms. While NTM are rarely associated with heart disease, including pericarditis, and pleural effusion, such presentations are exceptional. We report the case of an 85-year-old female who presented with polyserositis, characterized by pleural and pericardial effusion, and was diagnosed with an unusual manifestation of NTM infection causing pericarditis. Initially, the patient was misdiagnosed with tuberculosis, which delayed the correct diagnosis and appropriate treatment. Upon accurate diagnosis, her condition improved with adjustments to the treatment regimen. This case highlights the importance of considering NTM infection in the differential diagnosis, particularly when faced with atypical presentations. Early recognition and timely microbiological testing are crucial for accurate diagnosis, enabling targeted treatment and improving patient outcomes. LEARNING POINTS: Non-tuberculous mycobacteria infection can have non-specific presentations such as weight loss and night sweats, which are similar to lymphomas and tuberculosis.Unusual presentations of non-tuberculous mycobacteria infection, such as pleural effusions and pericarditis, can occur.Diagnosis is needed to ensure the correct treatment and may require polymerase chain reaction testing.