Treating Primary Arthroprosthesis Infection Caused byMycobacterium abscessussubsp. abscessus

Abstract

Prosthetic joint infections (PJI) caused by nontuberculous mycobacteria are very rare, and results of treatment can be unpredictable. A 72-year-old female underwent hip replacement after an accidental fall in a local hospital in Santo Domingo. The postoperative period was uneventful except for a traumatic wound near the surgical scar. PJI caused byMycobacterium abscessus subsp.abscessuswas diagnosed 6 months later. A two-stage reimplantation was performed after a 3-month period of aetiology-directed therapy, including amikacin, imipenem, and clarithromycin.M.abscessusisolate was reported to be resistant to clarithromycin when incubation was protracted for 14 days and to harbour the geneerm(41). The patient manifested major side effects to tigecycline. At reimplant, microbiologic investigations resulted negative. Overall, medical treatment was continued for a 7-month period. When discontinued and at 6-month follow-up, the patient was clinically well, inflammatory markers were normal, and the radiography showed well-positioned prosthesis.Mycobacterium abscessussubsp.abscessusis a very rare cause of PJI, yet it must be included in the differential diagnosis, especially when routine bacteria cultures are reported being negative. Further investigations are needed to determine any correlations between clinical results andin vitrosusceptibility tests, as well as the clinical implications ofM.abscessussubsp.abscessusharbouring the functional geneerm(41). Moreover, investigations are needed for determine optimal timings of surgery and lengths of medical therapy to improve patient outcome.