Abstract: The data of 4 patients with Mycobacterium murinum infection from October 30, 2019 to November 25, 2019 were analyzed retrospectively. Of four patients, one was male and three were females. The patients aged from 39 to 60 years old. They all were stabbed by sea bass and presented with infiltrating nodules on the hands or upper limbs. The biopsy of lesions showed infectious granulomas. The atypical mycobacteriosis were found in all patients. The treatment of clarithromycin combined with rifampicin and ethambutol was effective. 

Key words: Mycobacterium murinum infection, swimming pool granulomasea bass, atypical mycobacterium