Raul Colodner

Risk Factors for the Development of Extended-Spectrum Beta-Lactamase-Producing Bacteria in Nonhospitalized Patients

Although the risk factors for acquiring infection by extended-spectrum beta-lactamase (ESBL)-producing bacteria have been investigated in hospitalized patients, such risk factors have not been defined in the community setting. In this study, clinical data from a total of 311 nonhospitalized patients with community-acquired urinary tract infection (128 with ESBL-positive strains and 183 with ESBL-negative strains) were obtained. According to a multivariate analysis, the following were identified as independent risk factors: previous hospitalization in the past 3 months (OR=8.95, 95%CI, 3.77–21.25), antibiotic treatment in the past 3 months (OR=3.23, 95%CI, 1.76–5.91), age over 60 years (OR=2.65, 95%CI, 1.45–4.83), diabetes (OR=2.57, 95%CI, 1.20–5.51), male gender (OR=2.47, 95%CI, 1.22–5.01), Klebsiella pneumoniae infection (OR=2.31, 95%CI, 1.17–4.54), previous use of third-generation cephalosporins (P=0.014, OR=15.8, 95%CI, 1.7–143), previous use of second-generation cephalosporins (P<0.0001, OR=10.1, 95%CI, 4.2–24), previous use of quinolones (P=0.001, OR=4.1, 95%CI, 1.8–9.0), and previous use of penicillin (P=0.003, OR=4.0, 95%CI, 1.6–9.0).

Clinical, epidemiological, and microbiological features of Vibrio vulnificus biogroup 3 causing outbreaks of wound infection and bacteraemia in Israel

Summary Background Vibrio vulnificus is a gram-negative bacterium that causes septicaemia and wound infection. Cases occur sporadically, and no previous outbreaks due to a common source or a clonal strain have been reported. In the summer and autumn of 1996 and 1997, an outbreak of invasive V vulnificus infection occurred in Israel in people who had recently handled fresh, whole fish purchased from artificial fish-ponds. Methods We reviewed clinical and epidemiological information, and undertook an environmental investigation to assess disease characteristics, modes of transmission, phenotypic characteristics of the bacterium, and fish-marketing policy. The clonal nature of 19 isolates was studied by biotyping, pulsed-field gel electrophoresis, and restriction-fragment length polymorphism (RFLP) analysis of a PCR fragment. Findings During 1996–97, 62 cases of wound infection and bacteraemia occurred. 57 patients developed cellulitis, four had necrotising fasciitis, and one developed osteomyelitis. In all cases, the fish were cultivated in inland fish-ponds. In the summer of 1996, fish-pond managers initiated a new marketing policy, in which fish were sold alive instead of being packed in ice. Phenotypically, the isolates had five atypical biochemical test results. The isolates were non-typeable by pulsed-field gel electrophoresis, and all had the same PCR-RFLP pattern which had not been seen previously. Interpretation The cause of the outbreak was a new strain of V vulnificus , classified as biogroup 3. A new fish-marketing policy that began in 1996 may have exposed susceptible people to the organism.

Empiric use of trimethoprim-sulfamethoxazole (TMP-SMX) in the treatment of women with uncomplicated urinary tract infections, in a geographical area with a high prevalence of TMP-SMX-resistant uropathogens

This study evaluated whether trimethoprim-sulfamethoxazole (TMP-SMX) is effective for treatment of uncomplicated urinary tract infections (UTIs) due to TMP-SMX-resistant (TMP-SMX-R) pathogens. Healthy nonpregnant premenopausal women with symptomatic lower UTI were assessed for the presence of pyuria and bacteriuria; if either was present, a urine sample was cultured and TMP-SMX was prescribed. Clinical and microbiologic cure was assessed at days 5-9 and 28-42 after cessation of therapy. For 71%, of patients, cultures grew TMP-SMX-susceptible (TMP-SMX-S) microorganisms, and for 29%, cultures grew TMP-SMX-R organisms. Escherichia coli remained the predominant bacteria in both groups of cultures. At visit 2, microbiological cure had been achieved in 86% of the patients in the TMP-SMX-S group and 42% of those in the TMP-SMX-R group. Similar differences were found at visit 3 by clinical evaluation. Treatment with TMP-SMX of uncomplicated UTI caused by TMP-SMX-R microorganisms results in microbiologic and clinical failure. In high-resistance areas, TMP-SMX should not be the empiric drug of choice for uncomplicated UTI.

Procalcitonin as a marker of acute pyelonephritis in infants and children

Abstract In the absence of specific symptomatology in children, the early diagnosis of acute pyelonephritis is a challenge, particularly during infancy. In an attempt to differentiate acute pyelonephritis from lower urinary tract infection (UTI), we measured serum procalcitonin (PCT) levels and compared these with other commonly used inflammatory markers. We evaluated the ability of serum PCT levels to predict renal involvement, as assessed by dimercaptosuccinic acid (DMSA) scintigraphy. Serum C-reactive protein (CRP), leukocyte counts, and PCT levels were measured in 64 children admitted for suspected UTI. Renal parenchymal involvement was assessed by 99mTc-DMSA scintigraphy in the first 7 days after admission. In acute pyelonephritis, the median PCT level was significantly higher than in the lower UTI group (3.41, range 0.36–12.4 μg/l vs. 0.13, range 0.02–2.15 μg/l, P<0.0001). In these two groups, respectively, median CRP levels were 120 (range 62–249 mg/l) and 74.5 (range 14.5–235 mg/l, P=0.012) and leukocyte counts were 15,910/mm3 (range 10,200–26,900) and 14,600/mm3 (range 8,190–26,470, P=0.34). For the prediction of acute pyelonephritis, the sensitivity and specificity of PCT were 94.1% and 89.7%, respectively; CRP had a sensitivity of 100%, but a specificity of 18.5%. We conclude that serum PCT may be an accurate marker for early diagnosis of acute pyelonephritis.

Who Are You—Staphylococcus saprophyticus?

Staphylococcus saprophyticus is a leading cause of cystitis in young women. S. saprophyticus shares many clinical features of urinary tract infection caused by Escherichia coli, but differs in pathogenesis, seasonal variation, and geographic distribution. This review summarizes what is known and what still needs to be learned about this microorganism.

Effectiveness of Estriol-Containing Vaginal Pessaries and Nitrofurantoin Macrocrystal Therapy in the Prevention of Recurrent Urinary Tract Infection in Postmenopausal Women

We compared the efficacy and safety of estriol-containing vaginal pessary use with those of oral nitrofurantoin macrocrystal (NM) therapy for preventing urinary tract infection (UTI) in postmenopausal women with recurrent UTI. Over a period of 9 months, 86 women received an estriol-containing vaginal pessary (0.5 mg estriol) twice weekly, and 85 women received NM (100 mg) once daily. We recorded 124 episodes of UTI in women who received estriol-releasing pessaries and 48 episodes of UTI in women treated with NM (P=.0003). Twenty-eight women (32.6%) who received estriol had no episodes of UTI versus 41 women (48.2%) in the NM group. There was a significant increase in the number of superficial cells in women who received estriol, whereas in the NM group, no such changes occurred. However, there was no change in the extent of Lactobacillus colonization and in the vaginal pH in women who received estriol. Use of an estriol-containing pessary is less effective than oral NM therapy in the prevention of bacteriuria in postmenopausal women because of its failure to restore the population of lactobacilli and to reduce the vaginal pH in these women.

Distribution and characteristics of Escherichia coli clonal group A

Among 1,102 recent Escherichia coli clinical isolates, clonal group A was identified in 17 of 20 (U.S. and non-U.S.) geographic locales, mainly among U.S. isolates (9% vs. 3%; p < 0.001) and those resistant to trimethoprim-sulfamethoxazole (10% vs. 1.7%; p < 0.001). The extensive antimicrobial resistance and virulence profiles of clonal group A may underlie its recent widespread emergence.

Risk factors for community-acquired urinary tract infection due to quinolone-resistant E. coli.

Background:Resistance to fluoroquinolone drugs is emerging among E. coli causing community acquired urinary tract infections (COMA-UTI).Objectives:To evaluate demographic and clinical risk factors associated with COMA-UTI due to quinolone-resistant E. coli (QREc).Methods:In this case-control study, clinical and demographic data from 300 COMA-UTI due to E. coli (including 150 QREc) were analyzed.Results:By univariate analysis QREc was associated to males, older patients, nursing home residents, functionally dependent, dementia, diabetes, cardiovascular diseases, immunosupression, nephrolithiasis, recurrent UTI, invasive procedures, hospitalization, and antibiotic use within previous 6 months. By multivariate analysis, use of ciprofloxacin (OR 20.6 [CI 2.3–179.2], p = 0.006) or ofloxacin (OR 7.5 [CI 2.9–19.4], p < 0.0001), previous invasive procedure (OR 6.6 [CI 3.0–14.7], p < 0.0001), recurrent UTI (OR 4.7 [CI 2.3–9.3], p < 0.0001), and previous hospitalization (OR 2.9 [CI 1.4–6], p = 0.003) were identified as independent risk factors for COMA-UTI due to QREc.Conclusion:In patients with one or more of the risk factors identified here, the empiric use of quinolones should be reconsidered.

Urinary tract infection among women aged 40 to 65: Behavioral and sexual risk factors

We conducted a case-control study to explore the role of health behavior and sexual and medical history on urinary tract infection (UTI) risk among otherwise healthy women aged 40-65. Cases and controls were recruited from nine practices and clinics in Michigan and a single clinic in Israel. In both countries, several factors were reported significantly more frequently among UTI cases than controls: a previous UTI within 12 months, incontinence symptoms, a recent episode of 30-plus minutes of cold hands, feet, back or buttocks, and recent antibiotic use. Cases were less likely than controls to report recent estrogen use, but the results were only statistically significant in Michigan. Sexual activity during the previous 2 weeks and having ceased menses were modestly, but not statistically significantly, protective at both study sites. Risk factors for UTI among women 40-65 differ from those for younger women and these differences cannot be attributed solely to changes in menopausal status.

Ertapenem Resistance among Extended-Spectrum-β-Lactamase-Producing Klebsiella pneumoniae Isolates

ABSTRACT Ertapenem resistance in Klebsiella pneumoniae is rare. We report on an ertapenem-nonsusceptible phenotype among 25 out of 663 (3.77%) extended-spectrum-β-lactamase (ESBL)-producing K. pneumoniae isolates in a multicenter Israeli study. These isolates originated from six different hospitals and were multiclonal, belonging to 12 different genetic clones. Repeat testing using Etest and agar dilution confirmed ertapenem nonsusceptibility in only 15/663 (2.3%) of the isolates. The molecular mechanisms of ertapenem resistance in seven single-clone resistant isolates was due to the presence of ESBL genes (CTX-M-2 in four isolates, CTX-M-10 and OXA-4 in one isolate, SHV-12 in one isolate, and SHV-28 in one isolate) combined with the absence of OMPK36. Seven of 10 isolates initially reported as ertapenem nonsusceptible and subsequently classified as susceptible showed an inoculum effect with ertapenem but not with imipenem or meropenem. Population analysis detected the presence of an ertapenem-resistant subpopulation at a frequency of 10−6. These rare resistant subpopulations carried multiple ESBL genes, including TEM-30, SHV-44, CTX-M-2, and CTX-M-10, and they lacked OMPK36. The clinical and diagnostic significance of the results should be further studied.