Septic Prepatellar Bursitis due to Mycobacterium Massiliense

Background A man in his forties presented with pain, erythema, edema of his left knee. Four months prior to admission, patient suffered a left Achilles tendon rupture and was using an immobilization boot for 2 months. During that time patient had not noted any fever, chills or constitutional symptoms, but after the boot was removed, he was diagnosed with left knee bursitis and underwent drainage three times as outpatient with negative fluid cultures and with intra-articular steroids injection. Additionally patient was treated with oral doxycyline 100 mg every 12 hours for 5 days without clinical improvement. His past medical history was significant for hypertension, hyperlipidemia and obstructive sleep apnea. Patient had a past surgical history of inguinal hernia repair and septoplasty. Patient had no known allergies. His social history was negative for smoking, alcohol or substance abuse. Patient worked in an office-based job, had a dog at home and had travelled to Puerto Rico 3 weeks prior to his admission.