In vitro susceptibility to 19 agents other than β-lactams among third-generation cephalosporin-resistant Enterobacteriaceae recovered on hospital admission

Extended-Spectrum Beta-Lactamase-Producing Gram-Negative Bacteria on Healthcare Workers' Mobile Phones: Evidence from Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia

Background

Mobile phones are widely used in hospital settings for different purposes. Mobile phones of healthcare workers (HCWs) could be colonized or harbor extended-spectrum beta-lactamase (ESBL) producing gram-negative bacteria and may act as source of infectious agents. The aim of this study was to determine the rate of extended-spectrum beta-lactamase-producing Gram-negative bacteria on mobile phones of healthcare workers, to assess their antimicrobial susceptibility patterns and associated factors.

Methods

A laboratory-based cross-sectional study was conducted involving a total of 572 samples by rubbing swabs of the front screen, back, keypad, and metallic surfaces of mobile phones of healthcare workers using simple random sampling technique. All specimens were screened for ESBL using ESBL CHROME agar and confirmed using double-disk diffusion test (DDDT). Antibiotic susceptibility testing was done by the Kirby–Bauer disk diffusion technique on Mueller–Hinton agar. Data were analyzed using SPSS version 25, odds ratio and p-value was calculated to determine the association among variables.

Results

Overall, the number of mobile phones contaminated by gram-negative bacteria was 454 out of 572 (79.4%). Female sex (OR 0.651, p-value=0.039) and service year (OR 0.468, p-value=0.038) of healthcare workers were found to be the most significant factors associated with healthcare professionals’ mobile phone and bacterial contamination. Nine percent of the isolates were ESBL-producers. K. pneumoniae (27%) was the dominant ESBL-producing isolate followed by Acinetobacter spp. (14.5%) and E.coli (14.5%). ESBL-producers were highly resistant to ampicillin (95.8%), piperacillin (83.3%), cotrimoxazole (70.8%), and chloramphenicol (54.2%), but highly sensitive to meropenem (87.5%), amikacin (85.4%), and piperacillin-tazobactam (81.2%).

Conclusion

ESBL-producing Gram-negative bacteria were isolated from 8.3% of HCWs’ mobile phones. As high as 79.4% of the isolates were multidrug resistant. Mobile phones can lead to bacterial cross-contamination and could be a source of nosocomial infections.

ESBL colonization and acquisition in a hospital population: The molecular epidemiology and transmission of resistance genes

A prospective cohort study (German Clinical Trial Registry, No. 00005273) was performed to determine pre-admission colonization rates, hospital acquisition risk factors, subsequent infection rates and colonization persistence including the respective molecular epidemiology and transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (EPE). A total of 342 EPEs were isolated from rectal swabs of 1,334 patients on admission, at discharge and 6 months after hospitalization. Inclusion criteria were patients’ age > 18 years, expected length of stays > 48 hours, external referral. The EPEs were characterized by routine microbiological methods, a DNA microarray and ERIC-PCR. EPE colonization was found in 12.7 % of admitted patients, with the highest rate (23.8 %) in patients from nursing homes. During hospitalization, 8.1 % of the patients were de novo EPE colonized, and invasive procedures, antibiotic and antacid therapies were independent risk factors. Only 1/169 patients colonized on admission developed a hospital-acquired EPE infection. Escherichia coli was the predominant EPE (88.9 %), and 92.1% of the ESBL phenotypes could be related to CTX-M variants with CTX-M-1/15 group being most frequent (88.9%). A corresponding β-lactamase could not be identified in five isolates. Hospital-acquired EPE infections in patients colonized before or during hospitalization were rare. The diversity of the EPE strains was much higher than that of the underlying plasmids. In seven patients, transmission of the respective plasmid across different species could be observed indicating that the current strain-based surveillance approaches may underestimate the risk of inter-species transmission of resistance genes.

Ceftriaxone-associated nephrolithiasis and gallstone in adults

Background

Ceftriaxone (CTX) is widely used for the treatment of bacterial infections; however, side effects such as gallstone and nephrolithiasis have been reported in children. There is limited information about urinary tract calculi as CTX side effects in adults. Therefore, the present study was aimed to evaluate the incidence of gallstone and nephrolithiasis following CTX administration.

Methods

The present study was conducted in the Vali-e-Asr Hospital. Eighty-four patients with various infectious diseases with different daily treatment (mean ± SD: 4.19±2.54) were included in this study, consisting of 49 females and 35 males. The mean of total doses used in patients was 10.2143 (SD: 5.8585). To detect possible gallstone, gallbladder sludge, and urolithiasis, patients were evaluated by serial ultrasound before and after CTX treatment. Patients with renal and hepatobiliary dysfunction were excluded from the study and did not receive any nephrotoxic drugs during this study. Demographic parameters including age, sex, body mass index, dosage of CTX, as well as the duration of treatment and hospitalization were determined. Statistical significances were determined using Fisher’s exact test and independent t-test.

Results

Results from our study showed that the incidence of gallstone and nephrolithiasis were 8.8% and 1.5% following CTX administration, respectively. Surprisingly, we found a significant correlation in terms of age between patients with and without gallstone (P=0.03).

Conclusion

Our findings suggest that the patients’ age might play a role in the development of such a complication. This indicates the need for a close monitoring of CTX-treated patients to assess the possible formation of gallstone and nephrolithiasis.