Israel Medical Association Journal

Background: Skin colonization of microorganisms in blood cultures (BCs) are generally considered clinically non-significant and can be the source of a true infection, particularly in immunosuppressed patients.

Objectives: To study the epidemiology and risk factors for bacteremia caused by contaminants.

Methods: This retrospective, descriptive study is based on adult BCs collected (2004–2013) and categorized as positive (True bacteremia [TrueB] or contamination) or negative. Clinical, demographic, and laboratory characteristics of BCs positive for the six most common potential contaminant pathogens (PCPs) that can cause TrueB and contamination (Coagulase-negative Staphylococcus [CoNS], Streptococcus viridans, Propionibacterium acnes, Corynebacterium spp., Bacillus spp., Clostridium spp.) were assessed. Ninety-two TrueB were identified vs. 196 contaminations (1:2 ratio).

Results: From 74,014 BCs, PCPs were found in 3735 samples, of which 3643 (97.5%) were contaminations and 92 (2.5%) were TrueB. The overall rate of BC contamination decreased during the study period from 6.7% to 3.8%. CoNS was the most common PCP. Bacillus spp. were only contaminants. Clostridium spp. and Streptococcus viridans were more often TrueB. In a multivariate model, predictors of TrueB included high creatinine levels, Streptococcus viridans in BC, and multiple positive BCs. A single culture of CoNS was strongly predictive of contamination.

Conclusions: Ten years of data on BCs, focusing on six PCPs, demonstrates a significant, yet insufficient reduction in the rate of contamination. High creatinine level, isolation of Streptococcus viridans, and multiple positive BCs were predictors of TrueB, while growth of CoNS was strongly predictive of contamination. This model could assist in diagnostic and therapeutic decision making.

Background: Increasing antibiotic resistance in the community results in greater use of empiric broad spectrum antibiotics for patients at hospital admission. As a measure of antibiotic stewardship it is important to identify a patient population that can receive narrow spectrum antibiotics.

Objectives: To evaluate resistance patterns of Escherichia coli bloodstream infection (BSI) from strictly community-acquired infection and the impact of recent antibiotic use on this resistance.

Methods: This single center, historical cohort study of adult patients with E. coli BSI was conducted from January 2007 to December 2011. Patients had no exposure to any healthcare facility and no chronic catheters or chronic ulcers. Data on antibiotic use during the previous 90 days was collected and relation to resistance patterns was assessed.

Results: Of the total number of patients, 267 BSI cases met the entry criteria; 153 patients (57%) had bacteria sensitive to all antibiotics. Among 189 patients with no antibiotic exposure, 61% of isolates (116) were pan-sensitive. Resistance to any antibiotic appeared in 114 patients and 12 were extended-spectrum beta-lactamase (ESBL) producers. Quinolone use was the main driver of resistance to any antibiotic and to ESBL resistance patterns. In a multivariate analysis, older age (odds ratio 1.1) and quinolone use (odds ratio 7) were independently correlated to ESBL.

Conclusions: At admission, stratification by patient characteristics and recent antibiotic use can help personalize primary empirical therapy.

Background: Several types of human papillomavirus (HPV) have been found to be associated with oral squamous cell carcinoma (OSCC). Still, the significance of HPV infection and its relationship to patient prognosis remains an important matter of debate.

Objectives: To investigate the incidence of HPV infection in OSCC patients in northern Israel populations to determine its role in the etiology and prognosis of OSCC.

Methods: OSCC tissues were gathered from the pathology departments at Rambam and Padeh medical centers in northern Israel. HPV DNA typing and immunohistochemistry for p16INK4A antibodies were conducted to evaluate their incidence in OSCC tissues. Statistical analysis regarding its expression in the different sub-populations (Jews, Arabs, Druze) was conducted using chi-square and Fisher’s exact tests.

Results: The study included 82 patients: 53 men and 29 woman; median age 62.1 years; 54 Jews, 25 Arabs, and 3 Druze. The overall incidence of HPV expression was 45% (n=37). The median age of HPV-positive patients was 53 years vs. 65.8 in the negative group (P < 0.001). The 5 year overall survival of HPV-positive patients was not significantly higher than HPV-negative patients. A significant association was found between P16 expression and overall survival (log-rank P = 0.001).

Conclusions: HPV infection in OSCC was not found to be significant in this study; however, P16 expression in the tumor tissue was found to be a positive prognostic factor for better survival.

Background: Ureaplasma species (Usp) are the most prevalent genital Mycoplasma isolated from the urogenital tract of both men and women. Usp may be commensals in the genital tract but may also be contributors to a number of pathological conditions of the genital tract. Because they can also just colonize the genital tract of healthy people, their pathogenic role can be difficult to prove.

Objectives: The aim of the study was to evaluate the efficacy of a quantitative polymerase chain reaction (qPCR) method for the discrimination between infection and colonization by measuring prevalence of Usp in asymptomatic versus symptomatic patients.

Methods: Urine samples were tested for U. parvum and U. urealyticum using a semi-quantitative multiplex PCR technique for sexually transmitted diseases (Anyplex™ STI-7 Detection Kit, Seegene, South Korea). A total of 250 symptomatic and 250 asymptomatic controls were included.

Results: A strong positive result for U. parvum was significantly more prevalent in symptomatic compared to asymptomatic patients. This finding was observed especially in women and in the young group (15–35 years of age). No significant differences were observed between the prevalence in symptomatic and asymptomatic patients of U. parvum with low strength of positivity and for U. urealyticum in all groups by age, gender, and strength of positivity.

Conclusions: The significant difference between the symptomatic and asymptomatic group in the highest positivity group for U. parvum using the Anyplex™ STI-7 detection kit in urine may indicate a high probability of infection rather than colonization, especially in women and young patients.

Background: The authors describe a multifaceted cross-infection control program that was implemented to contain an epidemic of multidrug-resistant microorganisms (MRO) (carbapenem resistant Pseudomonas aeruginosa and Acinetobacter baumannii; extended spectrum β-lactamase producing Klebsiella pneumoniae, Escherichia coli, Enterobacter Cloacae, and Proteus mirabilis; and ‎methicillin-resistant Staphylococcus aureus and Candida species). 

Objectives: To assess the effect of a control program on the incidence of cross-infection with MRO.

Methods: Clinical criteria triaged patients into a high-risk wing (HRW) or a low-risk wing (LRW). Strict infection control measures were enforced; violations led to group discussions (not recorded). Frequent cultures were obtained, and use of antibiotics was limited. Each quarter, the incidence of MRO isolation was reported to all staff members. 

Results: Over a 6 year period, 1028 of 3113 patients were placed in the HRW. The incidence of MRO isolation within 48 hours of admission was 8.7% (HRW) vs. 1.91% (LRW) (P < 0.001). Acquired MRO infection density was 30.4 (HRW) vs. 15.6 (LRW) (P < 0.009). After the second year, the incidence of group discussions dropped from once or twice a month to once or twice a year.

Conclusions: These measures contained epidemics. Clinical criteria successfully triaged HRW from LRW patients and reduced cross-infection between the medical center wings. The quarterly reports of culture data were associated with improved staff compliance. MRO epidemic control with limited resources is feasible. 

 

Background: Little is known about the incidence of urinary tract infections (UTI) in the dispersed Bedouin population. UTIs are routinely treated empirically according to local resistance patterns, which is important when evaluating the risk factors and antibiotic resistance patterns in the Bedouin population.

Objectives: To analyze risk factors, pathogens, and antibiotic resistance patterns of UTIs in the Bedouin population compared to the general population in southern Israel. To compare data from this study to that from a previous study conducted at our center.

Methods: We prospectively followed all patients hospitalized with community acquired UTIs during a 4 month period at Soroka Medical Center. We also compared results from this study to those from a study conducted in 2000.

Results: The study comprised 223 patients: 44 Bedouin (19.7%), 179 (80.3) non-Bedouin; 158 female (70.9%), 65 male (29.1). The Bedouin were younger (51.7 vs. 71.1 years of age, P < 0.001) and had a lower Charlson Comorbidity Index (2.25 vs. 4.87, P < 0.001). Enterobacteriaceae were the most common pathogens identified, and Escherichia coli (E. coli) was the most common with 156 (70%) strains identified, followed by Klebsiella spp. with 29 (13%), Proteus spp. with 18 (8%), pseudomonas with 9 (4%), and other bacteria including enterococci with 11 (5%). The prevalence of E. coli increased significantly from 56% in 2000 to 70% in this study. We also noted an increase in community acquired extended spectrum beta lactamase (ESBL) pathogens from 4.5% in 2000 to 25.5% in the present study. No statistically significant difference was observed between the Bedouin and general populations in the causal pathogens, resistance to antibiotics, length of therapy, and readmission rate within 60 days. 

Conclusions: The Bedouin population hospitalized for UTIs is younger and presents with fewer co-morbidities. Isolated pathogens were similar to those found in the general population as was the presence of drug resistant infections. Overall, a substantial percentage of pathogens were resistant to standard first-line antibiotics, driving the need to change from empiric therapy to aminoglycoside therapy. 

 

Background: Accurate assessment of liver fibrosis is crucial for the management of patients with hepatitis C virus (HCV) infection.

Objectives: To evaluate the performance of liver segment-to-spleen volume ratio in predicting the severity of liver fibrosis.

Methods: Sixty-four consecutive HCV patients were enrolled in this retrospective study. All patients underwent contrast-enhanced computed tomography (CT) and were divided into three groups based on their hepatic fibrosis stage evaluated by shear-wave elastography (SWE): non-advanced (F0–F1, n=29), advanced (F2, n=19) and severe fibrosis (F3–F4, n=16). Using semi-automated liver segmentation software, we calculated the following liver segments and spleen volumes for each participant: total liver volume (TLV), caudate lobe (CV), left lateral segment (LLV), left medial segment (LMV), right lobe (RV) and spleen (SV), a well as their ratios: CV/SV, RV/SV, LLV/SV, LMV/SV and TLV/SV.

Results: RV/SV was found to discriminate between patients with non-advanced and advanced fibrosis (P = 0.001), whereas SV, CV, RV, TLV/SV, LMV/SV and RV/SV discriminated between patients with advanced and severe fibrosis (P < 0.05). RV/SV ≤ 3.6 and RV ≤ 2.9 were identified as the best cutoff values to differentiate non-advanced from advanced fibrosis and advanced from severe fibrosis with sensitivities of 72.2% and 92.7%, specificities of 72.7% and 77.8%, and with an area under the receiver operating characteristic (ROC) curve of 0.797 and 0.847, respectively (P ≤ 0.002).

Conclusions: RV/SV may be used for the assessment and monitoring of liver fibrosis in HCV patients prior to the administration of antiviral therapy, considering SWE as the reference method.

Background: The optimal approach to the evaluation of asymptomatic bacteruria in stroke patients is uncertain. 

Objectives: To compare elderly patients after an acute stroke with and without asymptomatic bacteriuria for the development of symptomatic urinary tract infections (UTI).

Methods: We prospectively monitored patients over 65 years of age admitted to our rehabilitation hospital after an acute stroke, with and without asymptomatic bacteriuria, for the development of symptomatic UTIs. The prevalence of bacteriuria was determined by urine cultures obtained 2 and 4 weeks after admission. Patients with and without persistent bacteriuria were compared to identify variables associated with bacteriuria.

Results: Fifty-five patients were included in the study. The prevalence of asymptomatic bacteriuria at baseline was 20%. Of all 55 stroke patients, 13 (23.6%) developed a symptomatic UTI during the 30 day follow-up. Patients with stroke and asymptomatic bacteriuria at baseline had an increased risk of developing a symptomatic UTI (54.5% with asymptomatic bacteriuria vs. 15.9% without, P = 0.011). To exclude the effects of several confounders, we performed multivariate Cox regression analysis, which showed that bacteruria remained a significant covariate for symptomatic UTI (hazard ratio 2.86, 95% confidence interval 0.71–10.46, P = 0.051). When subjects who experienced symptomatic urinary infection were included, the prevalence of bacteriuria in the study cohort declined to about 45.5% by 30 days. 

Conclusion: Elderly patients with stroke and asymptomatic bacteriuria have an increased risk of developing a symptomatic UTI compared to those without asymptomatic bacteriuria during a 30 day post-stroke follow-up.

 

Background: Antibiotic treatment of Clostridium difficile infection (CDI) has a high failure rate. Fecal microbiota transplantation (FMT) has proven very effective in treating these recurrences. 

Objectives: To determine which method of fecal microbiota transplantation (upper or lower gastrointestinal) and which type of donor (a relative or unrelated) is superior.

Methods: This is a retrospective analysis of treatment protocols and outcomes in 22 patients with refractory or recurrent CDI who underwent FMT at two Israeli facilities. Each center used a different donor type, stool preparation and method of delivery. The Tel Aviv Sourasky Medical Center used unrelated fecal donors and frozen stool samples and delivered them primarily (92%) via the lower gastrointestinal (GI) tract. Shaare Zedek Medical Center used fresh donor stool of relatives and delivered them primarily (90%) via the upper GI tract.

Results: FMT had an overall 2 month cure rate of 89%. Patients treated with FMT that was executed through the lower GI tract recovered faster from the infection (1.6 ± 1.08 vs. 2.4 ± 1 days for the upper tract, P = 0.03). The results also showed that patients who received lower GI tract FMTs were more likely to be cured of CDI (100% vs. 75% for upper tract FMTs, P = 0.16). Five patients (22%) died of CDI/FMT-unrelated causes and two (10%) died of CDI/FMT-related causes during the study period.

Conclusions: Lower GI tract FMT is a safe and effective treatment for refractory and recurrent CDI, and yields quicker results than upper GI tract FMT.