Co-Infection Pneumonia with Mycobacterium abscessus and Pneumocystis jiroveci in a Patient without HIV Infection Diagnosed by Metagenomic Next-Generation Sequencing

Co-infection pneumonia with ( ) and ( ) is rarely reported in previously healthy patients without HIV infection. The diagnosis of pneumonia of and remains challenging due to its nonspecific clinical presentation and the inadequate performance of conventional diagnostic methods. We report the case of a 44-year-old previously healthy male transferred to our hospital in February 2020 with a 4-month history of productive cough and one month of intermittent fever. At local hospital, the metagenomic next-generation sequencing(mNGS) detected sequences in blood; with the antifungal therapy (Caspofungin, trimethoprim-sulfamethoxazole [TMP-SMX] and methylprednisolone [MP]), the patient still had hypoxemia, cough and fever. Then he was transferred to our hospital, the mNGS of bronchoalveolar lavage fluid (BALF) detected the sequences of and . CD4+ T-lymphocytopenia in the peripheral blood cells was presented and HIV serology was negative. Caspofungin, TMP-SMX, clindamycin and MP were used to treat pneumonia (PJP). Moxifloxacin, imipenem cilastatin and linezolid were used to treat infection. Clinical progress was satisfactory following antifungal combined with anti- therapy. Co-infection pneumonia with and as reported here is exceptionally rare. mNGS is a powerful tool for pathogen detection. infection could be a risk factor for infection. This case report supports the value of mNGS in diagnosing of and , and highlights the inadequacies of conventional diagnostic methods.