title: Molecular Characterization of Cotrimoxazole Resistance Genes and Their Associated Integrons in Clinical Isolates of Gram-Negative Bacteria from Tanzania.
abstract: Cotrimoxazole is widely used, particularly as a prophylactic drug in HIV patients. We assessed resistance mechanisms among cotrimoxazole resistant-Gram negative bacterial isolates (n = 123) obtained from blood (n = 69) and urine (n = 54) from Tanzanian patients. sul genes were detected in 98% (121/123) of the isolates. Coexistence of sul1 and sul2 was common (49/123). The dfr genes were found in 63% (77/123) of all isolates. sul1, dfrA15, and dfrA5 genes predominated among Klebsiella pneumoniae, while sul2 and dfrA1 genes were frequent in Escherichia coli isolates. Two isolates, both K. pneumoniae, carried sul3. Integrons were detected in 81.3% (100/123) of all isolates. Class 1 integrons were found in 95% (42/44), 53% (23/43), and 80.6% (25/31) of K. pneumoniae, E. coli, and other Enterobacteriaceae isolates, respectively. Class 2 integrons were found in 14% of E. coli, but not in K. pneumoniae. All sul1 genes in K. pneumoniae were carried in class 1 integrons. Gene cassette arrays dfrA5 and dfrA15-aadA1 were most frequently associated with class 1 integrons, while class 2 integrons contained only dfrA1-sat2-aadA1 gene cassettes. This is the first report of sul3 gene in K. pneumoniae from human sources. The finding that mechanisms differ between E. coli and K. pneumoniae may broaden our understanding of cotrimoxazole resistance.
authors.affiliation: 1 Department of Clinical Science, University of Bergen , Bergen, Norway .|2 Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences (MUHAS) , Dar es Salaam, Tanzania .
authors.forename: Joel
authors.initials: J
authors.lastname: Manyahi
authors.affiliation: 3 Department of Medicine, National Centre for Tropical Infectious Diseases, Haukeland University Hospital , Bergen, Norway .
authors.forename: Marit Gjerde
authors.initials: MG
authors.lastname: Tellevik
authors.affiliation: 2 Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences (MUHAS) , Dar es Salaam, Tanzania .|4 Parliament of Tanzania, United Republic of Tanzania , Dodoma, Tanzania .
authors.forename: Faustine
authors.initials: F
authors.lastname: Ndugulile
authors.affiliation: 1 Department of Clinical Science, University of Bergen , Bergen, Norway .|2 Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences (MUHAS) , Dar es Salaam, Tanzania .
authors.forename: Sabrina J
authors.initials: SJ
authors.lastname: Moyo
authors.affiliation: 1 Department of Clinical Science, University of Bergen , Bergen, Norway .|3 Department of Medicine, National Centre for Tropical Infectious Diseases, Haukeland University Hospital , Bergen, Norway .
authors.forename: Nina
authors.initials: N
authors.lastname: Langeland
authors.affiliation: 1 Department of Clinical Science, University of Bergen , Bergen, Norway .|3 Department of Medicine, National Centre for Tropical Infectious Diseases, Haukeland University Hospital , Bergen, Norway .
authors.forename: Bjørn
authors.initials: B
authors.lastname: Blomberg
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003430:Cross-Sectional Studies; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000382:microbiology; D005798:Genes, Bacterial; D006801:Humans; D032023:Integrons; D007710:Klebsiella Infections / Q000188:drug therapy / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests; D011446:Prospective Studies; D013636:Tanzania; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology; D014552:Urinary Tract Infections / Q000188:drug therapy / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination
keywords: Gram-negative bacteria; Tanzania; cotrimoxazole resistance genes