A double pathogen strike: COVID-19 and talaromycosis Co-infection in a patient with post-tuberculosis lung disease

An 80-year-old woman from rural Guangxi with post-tuberculosis lung disease (PTLD) (hereinafter referred to as PTLD)presented with one month of cough and fever. One month prior, she had ingested raw rodent meat-a known exposure for Talaromyces marneffei. Chest HRCT showed bilateral tree-in-bud opacities superimposed on prior left lung destruction. Conventional microbiological tests, including acid-fast bacilli smears, were negative. A nasopharyngeal swab was positive for SARS-CoV-2 (cycle threshold 17). Metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid identified both T. marneffei and SARS-CoV-2. Her CD4⁺ count was 344/μL and HIV serology was negative. She received nirmatrelvir-ritonavir and sequential amphotericin B followed by voriconazole, with clinical and radiological improvement. This case illustrates that PTLD may serve as a local anatomical risk factor for talaromycosis even without systemic immunodeficiency.