Israel Medical Association Journal

Background: Healthcare workers (HCWs) have close interaction with confirmed or suspected coronavirus disease 2019 (COVID-19) patients. Infection rates reported among HCWs is between 3% and 17%, and asymptomatic HCWs are a potential source of nosocomial transmission to vulnerable patients and colleagues. Universal mask use and good supply of personal protective equipment was implemented early at our institution.

Objectives: To determine the rate of infection by the serologic status of HCWs during first three COVID-19 waves, based on occupation and risk of exposure, compared to Israeli general population.

Methods: We conducted a prospective cohort study at Emek Medical Center from April 2020 to April 2021. A total of 101 HCWs volunteered to be followed at six time points by a serology test and a questionnaire.

Results: A total of 101 HCWs completed six serologic tests. All participants were seronegative at the four initial tests. The cumulative seropositivity rate for COVID-19 in HCWs was 9.9% (10/101). Only three seropositive HCWs (2.97%) were hospital-acquired.

Conclusions: Seroprevalence and seroconversion dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in 101 HCWs during COVID-19 outbreaks at Emek Medical Center were similar to the epidemiological curve of positive polymerase chain reaction results of the Israeli population, as published by the Israeli Ministry of Health, at each time point. Universal mask use and infection control measures may have contributed to a low hospital infection rate.

Background: Patients with severe coronavirus disease-2019 (COVID-19) are susceptible to superimposed infections.

Objectives: To describe COVID-19 patients who presented with complications due to Candida bloodstream co-infection (candidemia) and their outcome in a single center in northern Israel (Emek Medical Center) during the second outbreak of COVID-19 in Israel (15 June 2020 to 20 September 2020).

Methods: A retrospective study of COVID-19 patients presenting with candidemia was conducted, including clinical and laboratory data. The incidence of candidemia among hospitalized COVID-19 patients was compared to a historical cohort of non-COVID-19 controls.

Results: Three COVID-19 patients complicated with candidemia were documented. All three patients died shortly after the detection of candidemia. Three different Candida sp. were isolated from the blood cultures: C. albicans, C. parapsilosis, and C. glabrata. The incidence of candidemia among COVID-19 patients was 0.679 episodes per 1000 hospital days.

Conclusions: Our small sample suggests a much higher incidence of candidemia among COVID-19 patients compared to a historical cohort of non-COVID-19 controls. All clinicians treating COVID-19 patients in GICU should be aware of this complication

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: 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: Recent studies show that vaccination of health care workers (HCW) might reduce influenza transmission and mortality among hospitalized patients. No studies have compared the incidence of laboratory-proven influenza in vaccinated versus unvaccinated hospital HCW. 

Objectives: To evaluate the effectiveness of influenza vaccination among hospital HCW and to examine the attitudes of this population towards influenza vaccination.

Methods: We performed a prospective cohort study between 1 January and 30 April 2014 of 1641 HCW at our medical center; 733 were vaccinated and 908 not vaccinated. A random sample of 199 subjects was obtained: 97 vaccinated and 102 non-vaccinated. Participating individuals were contacted on a weekly basis during the flu season and were asked to report any respiratory or flu symptoms and, if positive, to undergo a polymerase chain reaction (PCR) test for influenza. 

Results: In the general HCW population, vaccination was more frequent among physicians 298/498 (58%) than among nurses (324/862 (38%) and among males than females. Flu symptoms were reported by 20 of 199 participants, 13 in the non-vaccinated group (12.7%) and 7 in the vaccinated group (7.2%). A positive PCR test for influenza A virus was present in 4 of 20 people tested (20%). All positive cases were from the non-vaccinated group (P = 0.0953). 

Conclusions: Non-vaccinated HCW showed a higher, although not statistically significant, tendency for contracting laboratory-proven influenza than the vaccinated population. The main reasons for vaccination and non-vaccination were personal beliefs and habits. Education efforts are needed to improve compliance. Larger studies could further clarify this issue.

 

Background: Due to increasing antimicrobial resistance, there has been renewed interest in old drugs that have fallen into disuse because of toxic side effects. One such drug is chloramphenicol. Data on the use and susceptibility patterns to chloramphenicol in developed countries in recent years are limited.

Objectives: To assess the susceptibility of bacteria to chloramphenicol, and evaluate the use of chloramphenicol in Israeli hospitals as influenced by infectious disease specialists’ attitudes with regard to its potential harms.

Methods: A national survey was conducted in all Israeli hospitals. Questionnaires were sent to the directors of infectious disease units and included items on chloramphenicol susceptibility in clinical isolates, use of chloramphenicol for the treatment of inpatients, local recommendations for use of chloramphenicol, and concerns regarding side effects.

Results: Chloramphenicol is used in 83.3% of hospitals, mostly for the treatment of aspiration pneumonia. While 22.2% of infectious disease unit directors believe that chloramphenicol should be avoided because of dangerous side effects, 88.9% believe there is a place for chloramphenicol in the treatment of patients in this era of increasing antibiotic resistance. Chloramphenicol susceptibility is routinely assessed in 44.4% of hospitals, with high susceptibility rates found among gram-positive, gram-negative and anaerobic bacteria.

Conclusions: In an era of increasing antibiotic resistance, many Israeli infectious disease unit directors believe that chloramphenicol has a role in the treatment of respiratory tract and other infections in hospitalized patients.

Background: Community-acquired pneumonia is a common infection and is associated with high rates of morbidity and mortality. Most patients with CAP[1] are treated empirically.

Objectives: To identify common pathogens causing CAP in hospitalized patients in northern Israel and to evaluate the correlation between etiology and disease severity.

Methods: We conducted a prospective study of patients with CAP hospitalized at HaEmek Medical Center, Afula. We collected demographic, clinical and laboratory data (blood and sputum cultures, serology, pneumococcal urinary antigen test, and respiratory multiplex-polymerase chain reaction from nasopharyngeal swab), and radiologic evaluation was performed.

Results: A total of 126 patients and 24 controls were enrolled. At least one pathogen was identified in 84 cases (66.7%), more than one in 43 patients (34.1%), and no pathogens in 42 (33.3%). Typical bacteria were found in 23 (18.3%), atypical bacteria in 66 (52.4%), and viruses in 42 (33.3%). The number (%) of patients with pathogens isolated was: Chlamydophila pneumoniae 26 (20.6%), Streptococcus pneumoniae 23 (18.3%), Mycoplasma pneumoniae 23 (18.3%), influenza virus A-B 20 (15.9%), Coxiella burnetti 8 (6.3%), and parainfluenza and adenovirus 13 (10.3%) each. A correlation was found only between a high PORT score on admission and S. pneumoniae, although atypical pathogens did not show class predominance.

Conclusions: S. pneumoniae, M. pneumoniae and C. pneumoniae were the most common pathogens isolated, while co-infection was very frequent. PORT score did not predict any of the pathogens involved. The choice of empiric antimicrobial treatment for CAP should be made according to local epidemiologic data.

Background: Due to increasing antimicrobial resistance there has been renewed interest in old drugs that have fallen into disuse because of toxic side effects.

Objectives: To evaluate the susceptibility profile, in our hospital, of Enterobacteriaceae and Streptococcus pneumoniae isolates to chloramphenicol and to compare them with the susceptibility to amoxicillin-clavulanate.

Methods: All isolates of Enterobacteriaceae and S. pneumoniae recovered in our lab during a one year period were tested for susceptibility to chloramphenicol and amoxicillin-clavulanate or penicillin, respectively.

Results: Of 413 Enterobacteriaceae isolates, 182 (44.1%) were resistant to amoxicillin-clavulanate, but only 76 (18.4%) were resistant to chloramphenicol. Of 189 isolates of S. pneumoniae, 4 (2.1%) were highly resistant to penicillin and 73 (38.8%) were partially resistant, while only 2 (1.1%) were resistant to chloramphenicol. None of the 24 S. pneumoniae isolates causing invasive diseases exhibited resistance to chloramphenicol.

Conclusions: In an era of increasing resistance to many antibiotic preparations, chloramphenicol might have a role in the treatment of intraabdominal and respiratory tract infections.

Background: Identification of pathogens and their susceptibility to antimicrobials is mandatory for successful empiric antibiotic treatment.

Objectives: To compare the clinical characteristics of patients with bacteremia, as well as the bacterial distribution and antimicrobial susceptibility in community, hospital and long-term care facilities during two periods (2001–2002 and 2005–2006).

Methods: The study was conducted at the HaEmek Medical Center, a community 500-bed teaching hospital in northern Israel serving a population of ~500,000 inhabitants. All episodes of bacteremia (n=1546) during two 2 year periods (2001–2 and 2005–6) were prospectively recorded, evaluated and compared (755 in 2001–2 and 791 in 2005–6).

Results: In both periods the urinary tract was the main port of entry in community and long-term care facility bacteremia, while the urinary tract – primary and catheter-related – were similar in frequency as sources of hospital bacteremia. Escherichia coli was the most frequent pathogen isolate. No significant changes in the frequency of methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase-producing bacteria were seen between the two 2 year periods (2001–2 and 2005–6). The susceptibility of non-ESBL[1]-producing E. coli decreased for some antibiotics while non-ESBL-producing Klebsiella pneumoniae susceptibility profile improved in the same period. A non-statistically significant trend of increased resistance in gram-negative isolates to quinolones, piperacillin and piperacillin-tazobactam was observed, but most isolates still remained highly susceptible to carbapenems. There was a small increase in mortality rate in hospital bacteremia during the second period.

Conclusions: Continuous surveillance is imperative for monitoring the local epidemiology and for developing local treatment guidelines.

Background: In an era of increasing antimicrobial resistance, knowledge of local antimicrobial susceptibility patterns of common uropathogens is essential for prudent empiric therapy of community-acquired urinary tract infections.

Objectives: To define antimicrobial susceptibility of Gram-negative uropathogens in northern Israel over a 10 year period and to compare it with antibiotic-use patterns in the same community.

Methods: We tested the susceptibility of all Gram-negative urinary isolates from outpatients at HaEmek Medical Center over the years 1995, 1999, 2002 and 2005 to common antimicrobial agents. MIC₉₀ of Escherichia coli to some of these agents was determined and antibiotic consumption data over the years 2000–2005 (DDD/1000/day) were obtained.

Results: We observed a rise in susceptibility rates of E. coli to amoxicillin-clavulanate, trimethoprim-sulfamethoxazole and nitrofurantoin and of other Gram-negative isolates to amoxicillin-clavulanate, ceftriaxone and cephalothin. Susceptibility rates of all Gram-negative uropathogens to ciprofloxacin decreased significantly. MIC₉₀ of E. coli for all drugs tested remained stable. There was a significant decrease in the use nitrofurantoin and TMP-SMX[1] and a significant increase in the use of ampicillin, cephalothin and ceftriaxone.

Conclusions: Antibiotic resistance patterns mostly remained unchanged or improved slightly. There was, however, a constant decrease in susceptibility of all Gram-negative uropathogens to ciprofloxacin. Antibiotic use patterns could not explain the changes seen in antibiotic susceptibility patterns.

Background: The global spread of tuberculosis necessitates the development of an effective vaccine and new treatment modalities. That requires a better understanding of the differences in regulation of the immune responses to Mycobacterium tuberculosis between individuals who are susceptible or resistant to the infection. Previous immune studies in young Ethiopian immigrants to Israel did not demonstrate anergy to purified protein derivative or a Th2-like cytokine profile.

Objectives: To evaluate the profile of Th1 and Th2 cytokine production in immigrant TB patients, in comparison with asymptomatic control subjects.

Methods: The present study included (part 1): 39 patients with acute TB[1] (group 1), 34 patients with chronic relapsing TB (group 2), 39 Mantoux-positive asymptomatic TB contacts (group 3), and 21 Mantoux-negative asymptomatic controls (group 4). Patients were mainly immigrants from Eastern Europe and Ethiopia. Levels of interferon gamma, interleukin 2 receptor, IL-6[2] and IL-10 were measured in serum and in non-stimulated and PPD[3]-stimulated peripheral blood mononuclear cell culture supernatants, using commercial ELISA kits. In addition (part 2), levels of IFNg[4] and IL-12p40 were evaluated in 31 immigrant Ethiopian patients and 58 contact family members.

Results: Patients with acute disease tended to secrete more cytokines than contacts, and contacts more than chronic patients and controls, without a specific bias. None of the patients showed in vitro anergy. Discriminant probability analysis showed that from the total of 12 available parameters, a cluster of 6 (IFNg-SER[5], IFNg-PPD, IL-2R[6]-SER, IL-10-SER, IL-10-NS[7] and IL-6-PPD) predicted an 84% probability to become a TB contact upon exposure, 71% a chronic TB patient and 61% an acute TB patient. Family-specific patterns of IFNg were demonstrated in the second part of the study.

Conclusions: Firstly, no deficiency in cytokine production was demonstrated in TB patients. Secondly, acute TB patients secreted more cytokines than contacts, and contacts more than unexposed controls. Thus, neither anergy nor a cytokine dysregulation explains susceptibility to acute TB disease in our cohort, although chronic TB patients produced less cytokines than did acute patients and less than asymptomatic contacts. Thirdly, a certain cytokine configuration may predict a trend of susceptibility to acquire, or not acquire, clinical TB. It is presently unclear whether this finding may explain the disease spread in large populations. Finally, the familial association of IFNg secretion levels probably points towards a genetic regulation of the immune response to Mycobacterium tuberculosis.