Urinary tract infections caused by Shigella species

Molecular identification and antimicrobial resistance patterns of enterobacterales in community urinary tract infections among indigenous women in Ecuador: addressing microbiological misidentification

BACKGROUND

Antibiotic resistance of Enterobacterales poses a major challenge in the treatment of urinary tract infections (UTIs). In low- and middle-income countries (LMICs), standard microbiological (i.e. urine culture and simple disk diffusion test) methods are considered the "gold standard" for bacterial identification and drug susceptibility testing, while PCR and DNA sequencing are less commonly used. In this study, we aimed to re-identifying Enterobacterales as the primary bacterial agents responsible for urinary tract infections (UTIs) by comparing the sensitivity and specificity of traditional microbiological methods with advanced molecular techniques for the detection of uropathogens in indigenous women from Otavalo, Ecuador.

METHODS

A facility-based cross-sectional study was conducted from October 2021 to February 2022 among Kichwa-Otavalo women. Pathogens from urine samples were identified using culture and biochemical typing. Morphological identification was doble-checked through PCR and DNA sequencing of 16S, recA, and rpoB molecular barcodes. The isolates were subjected to antimicrobial susceptibility-testing using disk diffusion test.

RESULTS

This study highlighted a 32% misidentification rate between biochemical and molecular identification. Using traditional methods, E. coli was 26.19% underrepresented meanwhile Klebsiella oxytoca was overrepresented by 92.86%. Furthermore, the genera Pseudomonas, Proteus, and Serratia were confirmed to be E. coli and Klebsiella spp. by molecular method, and one Klebsiella spp. was reidentified as Enterobacter spp. The susceptibility profile showed that 59% of the isolates were multidrug resistant strains and 31% produced extended spectrum beta-lactamases (ESBLs). Co-trimoxazole was the least effective antibiotic with 61% of the isolates resistant. Compared to previous reports, resistance to nitrofurantoin and fosfomycin showed an increase in resistance by 25% and 15%, respectively.

CONCLUSIONS

Community-acquired UTIs in indigenous women in Otavalo were primarily caused by E. coli and Klebsiella spp. Molecular identification (16S/rpoB/recA) revealed a high rate of misidentification by standard biochemical and microbiological techniques, which could lead to incorrect antibiotic prescriptions. UTI isolates in this population displayed higher levels of resistance to commonly used antibiotics compared with non-indigenous groups. Accurate identification of pathogens causing UTIs and their antibiotic susceptibility in local populations is important for local antibiotic prescribing guidelines.

International travel and travelers' diarrhea - Increased risk of urinary tract infection

BACKGROUND

Urinary tract infections (UTIs) rank among the most common infections encountered in health care, with an annual incidence of 12% for women. Despite the vast numbers of international travels (over 1.5 billion annually), no prospective studies have had primary focus on UTIs during travel.

METHODS

We recruited in 2008-17 international travelers who all filled out pre- and post-travel questionnaires. Incidence rates of UTI were calculated separately for both sexes. Multivariable analyses were conducted to identify risk factors for UTI during travel.

RESULTS

In total 15/517 (2,9%) travelers acquired UTI during travel, yielding an annual incidence of 62% for female and 18% for male travelers. Travelers' diarrhea (TD) was identified as a factor predisposing to UTI (OR 9.2, 95% CI 1.5-+∞, p = 0.011); all UTI cases were recorded by travelers with TD.

CONCLUSIONS

To our knowledge, this is the first prospective study with a primary focus on UTI during travel. Our data reveal that among travelers the incidence of UTI far exceeds that reported for the general population. TD was identified as a major risk factor for the infection. Our results highlight the need for TD prevention as a means of also preventing UTI during travel.

Case report on a swift shift in uropathogens from Shigella flexneri to Escherichia coli: a thin line between bacterial persistence and reinfection

Background

Urinary tract infections (UTI) are mostly caused by bacteria. Urine cultures are usually a definitive measure to select the appropriate antibiotics for the elimination of a uropathogen and subsequent recovery from the infection. However, the preferred antibiotics as determined by urine culture and sensitivity may still not eliminate the infection and would require further examination to ascertain the cause of treatment failure which could be unresolved bacteriuria, bacterial persistence, immediate reinfection with a different uropathogen or misdiagnosis.

Case presentation

A 2-years 7 months-old female was admitted in the Regional hospital of Buea following persistent fever. An auto medication with amoxicillin was reported. Urinalysis was done on the first day and the sediment of the cloudy urine revealed many bacteria and few pus cells. Ceftriaxone was prescribed as empirical treatment and a request for urine and blood culture was made. Three days after admission, the temperature and CRP were 39.0 °C and 96 mg/l, respectively. The urine culture results (> 10⁵ CFU/ml of Shigella flexneri sensitive to ofloxacin) were presented to the doctor on the 4th day of admission. Patient was put on ofloxacin. Three days after, the temperature (38.5 °C) and CRP (24 mg/l) were still elevated. The blood culture result came out negative. A second urine culture was requested which came back positive (> 10⁵ CFU/ml of Escherichia coli resistant to ofloxacin and sensitive to meropenem and amikacin). Ofloxacin was discontinued and the patient put on meropenem and amikacin. The third urine culture recorded no significant growth after 48 h of incubation. The patient was discharged looking healthy once more with a normal body temperature.

Conclusion

Antibiotics tailored towards the elimination of a particular bacterial species may as well provide a favorable environment for other bacterial species that are resistant to it in the course of treating a UTI episode. This apparent treatment failure may first of all require a second urine culture for confirmation rather than considering the possibilities of a misdiagnosis.

Biomonitoring of the environmental indicator and pathogenic microorganisms assortment in foremost pilgrimage beaches of the Bay of Bengal, Southeast coast, India

The present study is aimed to monitoring the ecological indicator and pathogenic microorganism diversity in pilgrimage places beach sand on the Bay of Bengal coast. The samples were collected from three locations and four different sites, and were analyzed by following standard methods. The results clearly indicates, ritual activities were highly contaminated in the beach sand qualities, and exceeded with the standard permissible limit of WHO, USEPA, EU, CPCB beach sand recreational and other contacts activities including pH (11%), TBC (100%), TCB (97%), FCB (88%), TEB (75%), E. coli (75%), disease-causing possible level of Klebsiella (84%), Shigella (75%), Salmonella (63%) and Vibrio (56%). The statistical tools were applied to find the strong evidence. The current study pointed out the major effects on the diffusion of potentially pathogenic microorganisms along the shoreline provided useful information for the setup of measures for public health protection in the Bay of Bengal coast.