Dissemination of Aminoglycosides Resistance in Pseudomonas aeruginosa Isolates in Al-Diwaniya Hospitals

Pseudomonas aeruginosa is one of the primary opportunistic pathogens responsible for nosocomial infections. Aminoglycosides are an important component of antipseudomonal chemotherapy. Atotal of 350 clinical isolates were routinely collected . The isolates were classified according the source of collection to four groups (162 ear swab, 98 burn swab, 50 sputum samples and 40 urine samples). The results of culture and biochemical tests showed that 50 isolate was Pseudomonas aeruginosa, which then confirmed by API-20E. Antibiotic susceptibility test (by using the Kirby-pour technique) was performed to all these isolates , The results of antibiotic susceptibility test showed that 32 isolate (64%) resistance to at least one type of aminoglycosides which represented by gentamicin the highest (64%) and amikacin (26%) the lowest. The isolates that resistance to at least one type of aminoglycosides were screened for the presence of modifying enzyme genes (AACs, APHs, ANTs) and16S rRNA methylase genes by polymerase chain reaction. Five genes of AAC were found in 32 (64%) aminoglycosides resistant isolates, aac(6')-Ib (87.50%) was the most frequently identified gene, followed by aac(3)-II (31.25 %) , aac(6')-I (21.88%) , aac(3)-I (15.63%) and aac(6')-IIb (8.33%) . This study noted that the presence aph (3')-VI (25%) and ant (4')-IIb (21.88%) All of the isolates tested were exhibited positive results for the presence was the16rRNA methylase , armA (6.25%) was the lowest frequently identified gene among the16rRNA methylase genes , rmtA (31.25%) , rmtD (18.75%) , npmA (43.75%) was the most frequently identified gene among the16rRNA methylase genes .