Antimicrobial susceptibility of Helicobacter pylori strains isolated from children in Israel.

OBJECTIVES: Helicobacter pylori is a bacterial pathogen causing inflammation of the gastric mucosa that may lead to peptic ulcer, perforation or malignancy. Children are at risk of contracting H. pylori and developing subsequent morbidity. Diagnosis and management in children are difficult and merit a different approach compared with adults. This study aimed to describe the antimicrobial resistance rates of H. pylori to amoxicillin, tetracycline, clarithromycin, metronidazole, levofloxacin and rifampicin. METHODS: Biopsies (n=154) collected during endoscopic examinations were cultivated for 10days using a growth medium selective for H. pylori, of which 89 were H. pylori-positive. Antimicrobial resistance of the strains was assessed by Etest to establish minimum inhibitory concentrations (MICs) according to British Society for Antimicrobial Chemotherapy guidelines. RESULTS: Resistance rates were most notable for amoxicillin and clarithromycin at 12% and 35% with MICs of 0.74µg/mL and 2.51µg/mL, respectively. Resistance rates to tetracycline and levofloxacin were 8% and 2% with MICs of 2.57µg/mL and 2.0µg/mL, respectively. Resistance rates to rifampicin and metronidazole were 3% and 8% with MICs of 2.0µg/mL and 9.71µg/mL, respectively. CONCLUSION: Current rising antibiotic resistance rates for H. pylori are of concern. Performance of culture enables determination of the susceptibility profile, which may lead to a better choice of, and perhaps narrower spectrum, antibiotic agent. In light of these findings, we suggest that optimising the choice of antibiotic agent in children with H. pylori infection remains a challenge for clinicians and thus requires further investigation in randomised clinical trials.

[RESISTANCE OF HELICOBACTER PYLORI TO ANTIBIOTICS IN ISRAEL: PAST VS PRESENT].

INTRODUCTION: Helicobacter Pylori (H. Pylori) is a spiral shaped Gram-negative bacterium which is known to cause chronic gastric inflammation (gastritis) that could develop into a gastric or duodenal ulcer. The standard first line therapy for H. Pylori infection is a 7-14 days period of "triple therapy" consisting of proton pump inhibitors (PPI) and the antibiotics clarithromycin and amoxicillin or metronidazole. Recently there has been an increase in H. Pylori resistance to antibiotic treatment. Throughout the years 1999, 2002, 2010, 2013 and 2014 studies have been conducted in Israel that examined H. Pylori resistance rates for commonly used antibiotics. These studies included 40-138 participants who were diagnosed with infection caused by H. Pylori. Based on information derived from these studies, there is a clear increase in H. Pylori resistance to antibiotics, particularly to tetracycline, amoxicillin and clarithromycin.

Antimicrobial susceptibility of Clostridium difficile isolates in Israel.

OBJECTIVES: An increase of Clostridium difficile isolates with reduced susceptibility to various antimicrobial agents has been observed, including isolates that are non-susceptible to antibiotics that are routinely used for treatment of C. difficile, such as vancomycin and metronidazole. We determined the susceptibility rates of C. difficile isolates from hospitals in northern Israel to various antibiotics including tigecycline, which was not previously reported from Israel. METHODS: A total of 81 stool samples were collected from three hospitals in northern Israel from patients with C. difficile infection. Specimens were screened for BI/NAP1/027 ribotype, cultured, and sensitivity tests were performed for vancomycin, metronidazole, moxifloxacin, and tigecycline. Statistical tests were applied for analysing the differences in distribution of resistance between the different antibiotics and between BI/NAP1/027 and resistance of antibiotics. RESULTS: Reduced susceptibility was found among 6/81 isolates for vancomycin, 4/81 for metronidazole, and 17/81 for moxifloxacin. Only 1 isolate had reduced susceptibility to tigecycline, with a mean MIC of 0.05µg/mL. Reduced susceptibility to moxifloxacin was significantly associated with reduced susceptibility to vancomycin (p=0.016) and to metronidazole (p=0.0276), and reduced susceptibility to metronidazole was associated with reduced susceptibility to vancomycin (p=0.0259). Eight of 81 isolates (9.9%) were positive for BI/NAP1/027 ribotype and had significantly higher non-susceptibility rates to moxifloxacin and vancomycin compared with BI/NAP1/027 negative isolates (p<0.0001 and p=0.0113, respectively). CONCLUSIONS: We found higher non-susceptibility rates to vancomycin and metronidazole than most previous studies, while tigecycline resistance rates are very low in northern Israel, rendering it a potential agent for treating CDI.

Correlation between fecal calprotectin levels, disease severity and the hypervirulent ribotype 027 strain in patients with Clostridium difficile infection.

BACKGROUND: Clostridium difficile is the most common infectious etiology of nosocomial diarrhea. Fecal calprotectin (fc) is a sensitive marker of intestinal inflammation, found to be associated with enteric bacterial infections and inflammatory bowel disease. METHODS: We evaluated fc levels using a Chemiluminescent immunoassay method, in hospitalized patients with C. difficile infection (CDI) diagnosed by molecular stool examination and assessed correlation with virulent ribotype 027 strain infection, antibiotic susceptibility by gradient Etest strip performed on C. difficile colonies and clinical and laboratory measures of disease severity. Statistical analysis was performed for correlation of fc levels with clinical and laboratory parameters, disease severity and patient outcomes. RESULTS: Overall 29 patients with CDI were admitted at the Poria medical center in northern Israel, during June 2014-May 2015. Resistance to metronidazole was found in 3 (10.3 %) isolates and to vancomycin in 5 (17.2 %) isolates. Regarding patient outcomes, within 30 days of CDI diagnosis, recurrence of disease occurred in 10 (34.5 %) patients and 2 patients (6.9 %) died. Seven (24.1 %) isolates were C. difficile ribotype 027. Mean fc level was 331.4 µg/g (21-932). Higher fc levels were found in patients with C. difficile ribotype 027 (p < 0.0005). Fc levels were also correlated with elevated peripheral blood white cell count (p = 0.0007). A trend for higher fc levels was found in patients with a higher clostridium severity score index (p = 0.0633). No correlation was found between fecal calprotectin levels and age, sex, functional status, community versus hospital acquired CDI, antibiotic susceptibility, fever, and creatinine levels. CONCLUSIONS: Our study highlights the fact that fc has a potential role as a biomarker of disease severity and binary toxin producing ribotype associated disease.

Efficacy of an Enrichment Media for Increasing Threshold for Carbapenem-Resistant Enterobacteriaceae Screening.

BACKGROUND: Identification of carbapenem-resistant Enterobacteriaceae (CRE) is complex and a major laboratory challenge; clinical cultures may diagnose only some of the CRE carriers among patients, thus it is crucial to perform asymptomatic carriage screening. MATERIALS AND METHODS:  We compare the efficacy of a rectal sample culture prior to enrichment with BHI (Brain Heart Infusion) Broth and following 18-24 h. All rectal samples were applied on CHROMagar KPC selective growth media and then seeded on MacConkey agar selective growth media with an applied disk of Imipenem antibiotic on top of the media, then inserted into enrichment BHI Broth. After 18-24 h incubation with enrichment media, all samples were applied again on this media. RESULTS: From the 2,245 rectal samples, CRE colonies were found in 96 (4.3%). Following enrichment with BHI Broth, CRE colonies were found in 111 (4.9%) CHROMagar KPC plates and 106 (4.7%) MacConkey agar. CONCLUSION: We were able to demonstrate that the number of CRE-positive results increased due to use of additional enrichment with BHI Broth. Therefore, we recommend applying this method of addition of liquid enrichment media as part of a culture protocol routine for CRE screening.

Association of Streptococcus bovis presence in colonic content with advanced colonic lesion.

AIM: To prospectively examine the association between presence of Streptococcus bovis (S. bovis) in colonic suction fluid and the endoscopic findings on colonoscopy. METHODS: From May 2012 to March 2013, 203 consecutive patients who underwent colonoscopy for any reason were enrolled in the study. Exclusion criteria included: antibiotic use in the previous month, age younger than 18 years, and inadequate preparation for colonoscopy. The colonoscopy was performed for the total length of the colon or to the occluding tumor. The endoscopic findings were registered. Samples were obtained proximal to the colonoscopic part of the suction tube from each patient and sent to the clinical microbiology laboratory for isolation and identification of S. bovis. Samples were incubated in enrichment media with addition of antibiotic disks for inhibition of growth of Gram-negative rods. The samples were seeded on differential growth media; suspected positive colonies were isolated and identified with Gram staining, catalase, and pyrrolidonyl arylamidase tests, and further identified using a VITEK2 system. Statistical analyses were performed using the Student's t and χ(2) tests. RESULTS: Of the 203 patients recruited, 49 (24%) patients were found to be S. bovis carriers; of them, the endoscopic findings included: 17 (34.7%) cases with malignant tumors, 11 (22.4%) with large polyps, 5 (10.2%) with medium-sized polyps, 6 (12.2%) with small polyps, 4 (8.1%) with colitis, and 6 (12.2%) normal colonoscopies. Of 154 patients found negative for S. bovis, the endoscopic findings included: none with malignant tumors, 9 (5.8%) cases with large polyps, 11 (7.1%) with medium-sized polyps, 26 (16.9%) with small polyps, 7 (4.5%) with colitis, and 101 (65.6%) normal colonoscopies. S. bovis (Gram-positive coccus) is considered part of the normal intestinal flora. There is an association between S. bovis bacteremia and colonic neoplasia. It is not well understood whether the bacterium has a pathogenetic role in the development of neoplasia or constitutes an epiphenomenon of colorectal neoplasms. There was a clear relationship between positivity for S. bovis in colonic suction fluid and findings of malignant tumors and large polyps in the colon. CONCLUSION: There is an association between S. bovis bacteremia and malignant colonic lesions; this should prompt for development of a reliable screening method for advanced colonic lesions.

Catheter-associated candiduria: Risk factors, medical interventions, and antifungal susceptibility.

BACKGROUND: Catheter-associated candiduria is a common clinical finding in hospitalized patients, especially in the intensive care unit. The objective of this study was to obtain demographic and clinical data regarding the prevalence of Candida spp in catheterized in-patients and the medical interventions provided to these patients in a northern Israeli hospital between 2011 and 2013. METHODS: Isolation and identification of microorganisms were performed on 1,408 urine culture samples 48 hours after catheter insertion. Antifungal Etest susceptibility tests were carried out on every Candida-positive urine sample. Demographic and clinical data were gathered to determine risk factors and medical interventions. RESULTS: Candiduria was detected in 146 catheterized in-patients out of the 1,408 patients included in this study. C albicans was detected in most cases (69.1%). Fever was observed in 52 (35.61%) patients, and leukocyturia was observed in 48 cases (32.87%). Diabetes mellitus was associated with C albicans candiduria. There were 93 patients (63.69%) who did not receive any medical intervention for their candiduria. CONCLUSION: Candida is the second leading pathogen causing catheter-associated urinary tract infection or asymptomatic colonization, whereas previous studies showed Candida as the third leading pathogen. Clinical signs and symptoms, such as fever and laboratory tests, cannot distinguish between asymptomatic colonization and infection. Because the management of catheter-associated candiduria is still controversial, additional studies should be carried out.

An efficiency comparison between three invasive methods for the diagnosis of Helicobacter pylori infections: Culture from stomach biopsy, rapid urease test (CUTest(®)), and histologic examination of gastric biopsy.

BACKGROUND: Helicobacter pylori is one of the most prevalent pathogenic bacteria in the world, and humans are its principal reservoir. There are several available methods to diagnose H. pylori infection. Disagreement exists as to the best and most efficient method for diagnosis. METHODS: In this paper, we report the results of a comparison between three invasive methods for H. pylori diagnosis among 193 patients: culture, biopsy for histologic examination, and rapid urease test (CUTest(®)). RESULTS: We found that all three methods have a high sensitivity and specificity for the diagnosis of infections caused by H. pylori. However, the culture method, which is not used routinely, also showed high sensitivity, probably due to biopsies' seeding within 30 minutes, using warm culture media, non-selective media, and longer incubation. CONCLUSIONS: Although not a routine test, culture from biopsy can be meaningful in identification of antibiotic-resistant strains of H. pylori and should therefore be considered a useful diagnostic tool.

Improvement and optimization of the classical gastric biopsy culture technique for Helicobacter pylori diagnosis using trypsin.

Helicobacter pylori infection represents a key factor in the aetiology of various gastrointestinal diseases. H. pylori infection diagnosis is generally achieved using both invasive (e.g. biopsy of the gastric epithelium) and non-invasive methods. Therefore, cultivation on a growth medium becomes complex. Trypsin is a proteinase enzyme that plays a role in an early stage of tissue digestion. In this study, we used trypsin in order to improve the diagnostic sensitivity of the H. pylori cultivation technique. We used 46 duplicate antrum biopsy specimens, divided into trypsin-treated and non-treated groups. The tissues were seeded on a selective H. pylori growth agar medium. We demonstrated that the classic H. pylori culture technique misses the growth of a large number of H. pylori colonies. Significantly more colonies were found in the trypsin-treated specimens group.

Resistance of Helicobacter pylori to tetracycline, amoxicillin, clarithromycin and metronidazole in Israeli children and adults.

The aim of this study was to examine Helicobacter pylori-resistance rate to different antibiotics: tetracycline, amoxicillin, clarithromycin and metronidazole, and to compare eradication rates in adults and children in Israel. The study was based on the hypothesis of high-resistance rates to clarithromycin and metronidazole especially in adults and overall low-resistance rates to tetracycline and amoxicillin. One seventy six biopsies from patients with dyspeptic symptoms were cultured of which 100 were from adults (19-79 years) and 76 from children (7-17 years). All positive cultures were examined by Epsilometer test for MIC determination against tetracycline, amoxicillin, clarithromycin and metronidazole. 48.3% (85 out of 176) were H. pylori positive, of which 44% were from adults and 54% from children. Antibiotic resistance was seen in 31 out of 44 (70.5%) for metronidazole, 1 out of 44 (2.3%) for amoxicillin, 10 out of 44 (22.3%) for clarithromycin and 1 out of 44 (2.3%) for tetracycline among adults. Antibiotic resistance was seen in 10 out of 41 (24.4%) for metronidazole, 5 out of 41 (12.2%) for amoxicillin, 10 out of 41 (24.4%) for clarithromycin and 1 out of 41 (2.4%) for tetracycline among children. High rates of H. pylori resistance to metronidazole and clarithromycin was found especially among adults. Therefore, to increase the success rate of anti-H. pylori treatment, other classes of antibiotics need to be considered.

Do wheelchairs spread pathogenic bacteria within hospital walls?

Transmission of nosocomial pathogens has been linked to transient colonization of health care workers, medical devices and other constituents of patients' environment. In this paper we present our findings concerning the presence of pathogenic bacteria on wheelchairs, and the possibility that wheelchairs constitute a reservoir of these bacteria and a means of spreading them. In this work we examined four wheelchairs, each from a different location: the internal medicine ward, the emergency department, the general surgery ward and wheelchair stockpile of the transportation unit of the hospital. The samples were collected and cultured on different media. Bacterial identification and antimicrobial sensitivity testing were carried out using accepted practices in the microbiology laboratory. We found that wheelchairs are contaminated with several pathogenic bacteria, among them antibiotic-resistant strains such as MRSA, Pseudomonas aeruginosa, Acinetobacter baumanni etc. Since there is no specific guideline protocol that deals with disinfection and cleaning frequency of wheelchairs in hospitals, we suggest each hospital to write one.

A rare bacteremia caused by Cedecea davisae in patient with chronic renal disease.

PATIENT: Female, 77. FINAL DIAGNOSIS: Bacteremia. SYMPTOMS: Chills • diarrhea • fever • nausea. MEDICATION: - CLINICAL PROCEDURE: X-Ray • CBC • urine and blood cultur. SPECIALTY: Infectious diseases. OBJECTIVE: Rare disease. BACKGROUND: Cedecea davisae is a gram negative, oxidase negative bacilli that include 5 species. In the medical literature there are very few reports that describe infections caused by different species of the Cedecea genus. CASE REPORT: In this paper we report a fourth case of bacteremia in a 77 year-old patient with a chronic renal disease that was successfully treated with ceftazidim and ciprofloxacin. Additionally, we present a review of all the reported infections that were caused by C. davisae. CONCLUSIONS: Five cases (not including our report) of Cedecea bacteremia were reported so far. Cedecea infections and particularly C. davisae infections can be difficult to treat due to the antibiotic resistance of the bacterium. Therefore we propose to consider treating C. davisae bacteremia with a combined antibiotic treatment until getting laboratory results for antibiotic-sensitivity tests.