Clinical Microbiology: Open Access

Abstract

Threatening Problem of Stenotrophomonas maltophilia Producing Extended-Spectrum Beta-Lactamases: Prevalence and Automated Antibiotic Susceptibility Pattern

Nada Abdel-Aziz, Mohamed-Mofeed Fawaz Morsy, Sahar Saadallah Amin, Kawthar I Mohammed, Ahmed E Alharbi and Issam Alshami

Background: Stenotrophomonas maltophilia (S. maltophilia) is one of the most common emerging multi-drug resistant organisms. It is associated with difficult detection, treatment, and increased mortality particularly among immune compromised and debilitated individuals. Objectives: To determine the prevalence and antibiotic susceptibility pattern of S. maltophilia as emerging problem from different clinical isolates. Methods: A cross sectional study was conducted on 14000 cases. The isolates of Gram negative bacilli were identified based on conventional microbiological procedures. Extended spectrum beta lactamases (ESBLs) producing S. maltophilia identification and antibiotic susceptibility was further confirmed using automated BD Phoenix system where the panel of Gram negative antibiotics was tested. Results: Out of 14000 reviewed cases, 2100 were proved to be culture positive. Among Gram negative isolates, 1.5% was proved to be S. maltophilia. One hundred fourteen of Gram negative isolates were proved to be ESBL producers. More than half of ESBL isolates were E-coli. S. maltophilia represents (8.77%) of total Gram negative ESBL producers, while ESBL producing S. maltophilia represent (83.33%) among the total number of S. maltophilia isolates. Half number of S. maltophilia isolates was obtained from blood. About 83 % of S. maltophilia isolates showed resistance to all Gram negative Panels of antibiotics, while 100% of isolates were sensitive to Trimethoprimsulfamethoxazole (TMP – SXT). 16.67% of isolates showed sensitivity to ciprofloxacin (CIP), ceftazidime (CAZ). Conclusion: ESBL producing S. maltophilia is frequently resistant to a wide range of commonly used antimicrobials. Routine sensitivity reporting is required to detect these threatening, multidrug resistant organisms. Trimethoprim-sulfamethoxazole (TMP – SXT) is recommended as the agent of choice for the treatment of S. maltophilia infections. Alternatively, fluoroquinolones and ceftazidime (CAZ) may be used.