Israel Medical Association Journal

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.

 

Objectives: To evaluate the performance of the C. DIFF QUIK CHEK COMPLETE^® assay, designed to simultaneously detect C. difficile-produced glutamate dehydrogenase (GHD) and toxins A and B.

Methods: Using the C. DIFF QUIK CHEK COMPLETE assay, the Tox A/B EIA, and polymerase chain reaction (PCR), we tested 223 stool specimens from hospitalized patients with antibiotics-associated diarrhea. Sensitivity and specificity, and positive and negative predictive values (PPV, NPV) were calculated for the C. DIFF QUIK CHEK COMPLETE test and the Tox A/B EIA against PCR

Results: The C. DIFF QUIK CHEK COMPLETE test had a sensitivity of 83.5% and specificity of 94.3% compared to PCR for Tox A/B, with 93.7% correlation (PPV 98.5%, NPV 91.7%). The Tox A/B EIA yielded corresponding values of 72.1% and 93.1%, with 85.6% correlation (PPV 85.1%, NPV 85.8%).

Conclusions: Given the importance of an early and appropriate diagnosis of Clostridium difficile-associated infection, the C. DIFF QUIK CHEK COMPLETE test may be of huge benefit to practitioners.

Objectives: To retrospectively analyze the results of a screening program for C-CMV performed at the Sheba Medical Center, Tel Hashomer, during a 1 year period, using real-time polymerase chain reaction (rt-PCR) from umbilical cord blood.

Methods: CMV DNA was detected by rt-PCR performed on infants’ cord blood. C-CMV was confirmed by urine culture (Shell-vial). All confirmed cases were further investigated for C-CMV manifestations by head ultrasound, complete blood count, liver enzyme measurement, ophthalmology examination and hearing investigation.

Results: During the period 1 June 2009 to 31 May 2010, 11,022 infants were born at the Sheba Medical Center, of whom 8105 (74%) were screened. Twenty-three (0.28%) were positive for CMV and 22 of them (96%) were confirmed by urine culture. Two additional infants, who had not been screened, were detected after clinical suspicion. All 24 infants were further investigated, and 3 (12.5%) had central nervous system involvement (including hearing impairment) and were offered intravenous ganciclovir for 6 weeks. Eighteen (82%) infants would not otherwise have been diagnosed.

Conclusions: The relatively low incidence of C-CMV detected in our screening program probably reflects the low sensitivity of cord blood screening. Nevertheless, this screening program reliably detected a non-negligible number of infants who could benefit from early detection. Other screening methods using saliva should be investigated further.

Background: During an influenza pandemic, clinicians need easily available clinical and laboratory criteria to distinguish influenza from similar respiratory illnesses. We compared A/H1N1/2009-polymerase chain reaction (PCR)-positive and matched PCR-negative hospitalized patients with suspected H1N1 influenza to identify factors that could assist physicians at patient admission.

Objectives: To identify factors significantly associated with A/H1N1/2009 infection.

Methods: A group of 145 patients with PCR-confirmed A/H1N1 2009 influenza admitted between 27 May 2009 and 3 December 2009 was matched with 145 PCR-negative patients by age, epidemiological week and pregnancy status. Epidemiological and clinical parameters and radiological findings on initial chest X-ray were compared between the two groups.

Results: Asthma (PCR+ 26%, PCR- 12%, P = 0.006) and military service (PCR+ 13%, PCR- 4%, P = 0.15) were associated with PCR-positive status in non-pregnant patients. At presentation, fever, cough, myalgia and fulfilling the pandemic influenza case definition were significantly more frequent in non-pregnant PCR+ patients (62/90/43/59% in PCR+ versus 38/69/30/35% in PCR-). In pregnant patients, fever and fulfilling the case definition were significantly associated with PCR-positive status. Mean leukocyte and absolute lymphocyte counts were significantly lower in both pregnant and non-pregnant PCR-positive patients. Significantly more PCR-negative non-pregnant patients (43% vs. 22% PCR+, P = 0.004) had abnormal chest X-ray (CXR) findings on presentation. In PCR-positive patients, patchy consolidation and interstitial infiltrates were the most common abnormalities.

Conclusions: Under the conditions generated by the A/H1N1/2009 pandemic, radiological findings did not distinguish reliably between influenza and other febrile respiratory illnesses. Asthma, military service, the pandemic case definition (particularly fever, cough and myalgia) and lymphopenia were associated with confirmed H1N1 infection.
 

Background: The rate of infection with Clostridium difficile colitis and its associated mortality have been increasing in the last decade. The molecular epidemiology of C. difficile in Israel has as yet not been studied.

Objectives: To screen for the existence of the 027 and 078 ribotypes and determine the longitudinal molecular epidemiology of the circulating clinical C. difficile isolates in a large hospital in central Israel.

Methods: Polymerase chain reaction (PCR) ribotyping was performed on C. difficile isolates obtained from hospitalized patients from November 2003 to May 2004 (first study period) and September 2009 (second study period). Isolates with PCR[1] ribotype patterns, unlike those of the available reference strains (078 and 027), were labeled with letters. Forty-six isolates from the first study period and 20 from the second were analyzed.

Results: PCR strain typing of C. difficile isolates yielded approximately 26 unique ribotypes. During the first study period, ribotype A and B accounted for 30% and 28%, respectively, whereas ribotype E and K accounted for 6.5% for each. During the second study period, ribotypes A, E and K disappeared, and the incidence of ribotype B decreased from 28% to 15%. One isolate (1/20, 5%) emerged during the second period and was identified as ribotype 027. Moxifloxacin resistance was found in 93% of ribotype A isolates, 81% of the ribotype B group, and in 44% of other ribotypes.

Conclusions: The predominant ribotypes circulating in our institution were diverse and changing. This is the first report on the emergence of the 027 ribotype in Israel.

Background: An outbreak of pertussis occurred in a daycare center with 87.5% vaccination coverage.

Objectives: To assess the effectiveness of the acellular pertussis vaccine and prevention of pertussis after chemoprophylaxis with azithromycin.

Methods: We studied 31 daycare children aged 3–5.5 years exposed to a child with pertussis. Nasopharyngeal swabs were obtained for Bordetella pertussis culture and polymerase chain reaction initially, and at days 21 and 60 of follow-up, in cases exhibiting symptoms.

Results: Of the 31 daycare children 6 (19%) tested positive for B. pertussis by PCR[1], 4 of whom had not been vaccinated against the disease. Of the two vaccinated children who contracted pertussis, one had milder symptoms and the other was asymptomatic. The incidence of pertussis was significantly lower in the vaccinated group (2/27) than in the unvaccinated group (4/4) (P = 0.000), with efficacy of the vaccine calculated to be 92.5%. Azithromycin chemoprophylaxis was taken only by 14 of the 25 exposed children (56%). On day 21 follow-up, there was no further laboratory-diagnosed B. pertussis cases in any of the exposed children, regardless of whether or not chemoprophylaxis was taken.

Conclusions: Based on the children’s clinical manifestations and PCR findings a pertussis outbreak had occurred in the daycare center studied. Our findings support the importance of pertussis vaccination since all the unvaccinated children in the daycare center contracted the infection.

Background: Adenoviral infection in children undergoing stem cell transplantation is associated with significant morbidity and mortality. Identification of adenoviral infection by polymerase chain reaction from blood facilitates accurate and rapid diagnosis and surveillance. The incidence of adenoviral infection among children undergoing SCT[1] in Israel is not known.

Objective: To estimate the incidence of adenoviral infection in pediatric SCT patients and to characterize the morbidity associated with proven infection.

Methods: Blood samples obtained weekly from children who underwent allogeneic SCT were retrospectively tested for adenovirus using standard PCR[2]. A total of 657 samples collected from 32 patients were examined. Correlation was made between the presence of adenovirus in samples and clinical records.

Results: Of the 32 patients 4 had adenoviral infection by PCR (12.5%). Clinical disease was present in all four patients concurrent with positive PCR. Gastrointestinal complaints and abnormal hepatocellular enzymes were uniformly present. One patient died due to disseminated disease. T cell depletion was a significant risk factor for adenoviral infection (P = 0.03).

Conclusions: In the patient population studied, the incidence of adenoviral infection in children undergoing SCT was 12.5%. The combination of gastrointestinal symptoms and abnormal hepatocellular enzymes should raise the suspicion of adenoviral infection, especially when occurring during the first few months after SCT. 

Background: According to the U.S. Centers for Disease Control guidelines, prolonged rupture of membranes mandates intrapartum antimicrobial prophylaxis for group B Streptococcus whenever maternal GBS[1] status is unknown.

Objectives: To evaluate the local incidence, early detection and outcome of early-onset GBS sepsis in 35–42 week old neonates born after PROM[2] to women with unknown GBS status who were not given intrapartum antimicrobial prophylaxis.

Methods: During a 1 year period, we studied all neonates born beyond 35 weeks gestation with maternal PROM ≥ 18 hours, unknown maternal GBS status and without prior administration of IAP[3]. Complete blood count, C-reactive protein, blood culture and polymerase chain reaction amplification of bacterial 16S rRNA gene were performed in blood samples collected immediately after birth. Unfavorable outcome was defined by one or more of the following: GBS bacteremia, clinical signs of sepsis, or positive PCR[4].

Results:  Of the 3616 liveborns 212 (5.9%) met the inclusion criteria. Only 12 (5.7%) of these neonates presented signs suggestive of sepsis. PCR was negative in all cases. Fifty-eight neonates (27.4%) had CRP[5] > 1.0 mg/dl and/or complete blood count abnormalities, but these were not significantly associated with unfavorable outcome. Early-onset GBS sepsis occurred in one neonate in this high risk group (1/212 = 0.47%, 95% CI 0.012–2.6). 

Conclusions: In this single-institution study, the incidence of early-onset GBS sepsis in neonates born after PROM of ≥ 18 hours, unknown maternal GBS status and no intrapartum antimicrobial prophylaxis was 0.47%.

The Israel Ministry of Health’s epidemiology department reported a record number of 1564 new pertussis cases in 2004. This brings the incidence rate to 23 per 100,000 population, indicating a marked increase in the prevalence of pertussis, from 1–3/100,000 in 1998, 9 in 2001, to 14 in 2003. The rate of atypical pertussis presentations in vaccinated patients, the decline in pertussis immunity post-vaccination, and the decreased awareness of potential infections in the adult population make the diagnosis of pertussis difficult and contribute to the rising incidence. In this article we review the current literature in order to increase awareness of the occurrence of pertussis in children as well as adults, discuss the laboratory diagnostic methods being used, and report the currently recommended means of treating the disease.

Objectives: To assess the relative efficacy of clinical and laboratory methods in the diagnosis of Bordetella pertussis by patient age and immunization status.

Methods: We compared the clinical and laboratory diagnosis of B. pertussis in 87 pre-vaccinated, 78 recently vaccinated, and 75 post-vaccinated children with suspected pertussis. Serum and nasopharyngeal swabs were obtained for serology, culture and polymerase chain reaction.

Results: PCR[1] and culture identified 41% and 7% of patients with B. pertussis, respectively (P < 0.001). All positive cultures were PCR-positive. Positive PCR was less common among those recently vaccinated than among those in the pre- (P < 0.001) and post-vaccinated groups (P < 0.05). Positive culture was more common among those pre-vaccinated than among those recently vaccinated (P < 0.01). Positive tests for immunoglobulin M and A were more common among the post-vaccinated than the pre- and recently vaccinated (P < 0.001), respectively. Logistic regression analyses revealed that clinical criteria have no significant association with infection in recently and post-vaccinated children. Among the pre-vaccinated children, whoop and cough duration were associated with a positive PCR (odds ratio 7.66 and 0.5, P < 0.001). Seventy-six percent of pre-vaccinated, 39% of recently vaccinated and 40% of post-vaccinated children with positive PCR did not meet the U.S. Centers for Disease Control diagnostic criteria for B. pertussis.

Conclusions: PCR is a useful tool for pertussis diagnosis, particularly in pre-vaccinated infants. The yield of culture and serology is limited, especially among pre- and recently vaccinated children. In pre-vaccinated infants with whoop and less than 2 weeks of cough, PCR testing should be implemented promptly.