title: Emergence of resistance to clarithromycin during treatment of disseminated cutaneous Mycobacterium chelonae infection: case report and literature review.
abstract: Results of in vitro susceptibility studies and one clinical trial have led to recommendations of clarithromycin monotherapy for the treatment of disseminated cutaneous Mycobacterium chelonae infections. We describe the case of a 65-year-old woman, immunocompromised by the use of chronic steroid therapy, who developed disseminated cutaneous infection with M. chelonae and failed clarithromycin monotherapy due to the development of drug resistance. In the relapse isolate we document the presence of a single point mutation at position 2058 in the gene coding for 23S rRNA peptidyltransferase regions, a mutation previously implicated in the development of resistance to clarithromycin. Two susceptible control isolates lacked the mutation. Three additional reports in the literature of patients developing recurrent skin lesions with clarithromycin-resistant M. chelonae following initial response to monotherapy are summarized. We demonstrate that clarithromycin monotherapy in patients with disseminated cutaneous infections can lead to clarithromycin resistance and therapeutic failure associated with a single point mutation at position 2058 of 23S rRNA.
authors.affiliation: Division of Infectious Diseases, Department of Medicine, Medical University of South Carolina and Ralph H. Johnson VA Medical Center, Charleston, South Carolina, USA.
authors.forename: R K
authors.initials: RK
authors.lastname: Vemulapalli
authors.forename: J R
authors.initials: JR
authors.lastname: Cantey
authors.forename: L L
authors.initials: LL
authors.lastname: Steed
authors.forename: T L
authors.initials: TL
authors.lastname: Knapp
authors.forename: N M
authors.initials: NM
authors.lastname: Thielman
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017291:Clarithromycin / Q000627:therapeutic use*; D004351:Drug Resistance / Q000235:genetics; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D008826:Microbial Sensitivity Tests; D009165:Mycobacterium Infections, Nontuberculous / Q000188:drug therapy* / Q000382:microbiology / Q000473:pathology; D016926:Mycobacterium chelonae / Q000187:drug effects* / Q000235:genetics; D010458:Peptidyl Transferases / Q000235:genetics; D017354:Point Mutation; D012338:RNA, Ribosomal, 23S / Q000235:genetics; D017192:Skin Diseases, Bacterial / Q000188:drug therapy* / Q000473:pathology; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D012338:RNA, Ribosomal, 23S; D010458:Peptidyl Transferases; D017291:Clarithromycin