Department of Microbiology, Sir Salimullah Medical College, Mitford, Dhaka, Bangladesh
Background and objectives: Emergence of
extended spectrum beta-lactamase (ESBL) producing bacteria is a major
public health concern. Detection of multi drug resistant (MDR) ESBL
producing organisms is necessary to prevent its spread and effective
treatment. The purpose of the present study was to determine the
magnitude of ESBL producing organism in hospital setting and to compare
the suitability of double disc synergy test (DDST) and
cefepime-clavulanate E-test method for the detection of ESBL producing
organisms in routine microbiology laboratory.
Materials and methods:
The study was carried out in the Department of Microbiology, Sir
Salimullah Medical College, Dhaka from January 2011 to December 2011.
Clinical samples included urine and pus from patients with suspected
urinary tract and wound infections respectively. Standard
microbiological methods were employed for isolation and identification
of the organisms. DDST and E-test were used to detect ESBL producing
Gram negative organisms.
A total of 186 Gram-negative organisms were isolated from various
samples. Among the 186 Gram negative bacteria, 120 (64.5%) were Esch. coli while 33 (17.7%), 20 (10.8%) and 11 (5.9%) were Pseudomonas sp, Klebsiella sp and Proteus
sp respectively. Out of total 186 isolates, 77 (41.4%) and 73 (39.2%)
isolates were found ESBL producers by DDST and E-test method (p=0.674)
respectively. Compared to Escherichia coli, Pseudomonas and Proteus, significantly high (p<0.01) proportion of Klebsiella
were ESBL positive by both DDST and E-test methods. The detection rate
of ESBL producing organisms was not significantly different by DDST and
E-test (41.4% vs 39.2%). Non-determinable result was obtained for 4
(2.2%) isolates by E-test method.
Conclusion: In our present
study, a substantially large number of clinical isolates were found
ESBL producers. Compared to E-test, DDST was found as a reliable,
convenient and inexpensive method for detection of ESBL producing
organism in routine microbiology laboratory practice.
IMC J Med Sci 2018; 12(1): 32-36