Israel Medical Association Journal

Background: The kinetics of high sensitivity cardiac troponin T (hs-cTnT) levels after elective, biphasic, direct-current cardioversion for persistent atrial fibrillation/flutter remains unknown.

Methods: We examined hs-cTnT kinetics in 24 patients at baseline and at 2, 6 and 24 hours post-cardioversion, and again at 7 and 30 days. We also examined levels of creatine kinase, aspartate aminotransferase, lactate dehydrogenase, brain natriuretic peptide (BNP), and high sensitivity C-reactive protein (hs-CRP).

Results: Median (25th, 75th interquartiles) baseline hs-cTnT concentration was 19.8 (10.4, 35.2) ng/L with 14 patients presenting with levels above the 99th percentile (13 ng/L). Hs-cTnT levels did not change significantly over time although they tended to decrease by 30 days, 18.8 ng/L (12.5, 23.3). There was no significant rise in other markers of myocardial injury. Similarly, BNP and hs-CRP levels were elevated at baseline and tended to decrease over time.

Conclusions: Patients with persistent atrial fibrillation/flutter have elevated hs-cTnT levels, as part of a general rise in biomarkers such as BNP and hs-CRP, without a further rise after cardioversion. After cardioversion, there is a gradual non-significant decrease in biomarker levels over time, and thus a rise in hs-cTnT levels should not be attributed to cardioversion. 

 

Background: Predictive biomarkers for personalized treatment of neoplasms are suggested to be a major advancement in oncology and are increasingly used in clinical practice, albeit based on level II evidence. Target Now® (TN) employs immunostaining and RNA expression on tumor samples to identify potentially beneficial or ineffective drugs. 

Objectives: To explore retrospectively the predictive value of TN for patients with colorectal and gastric carcinomas. 

Methods: The study group comprised colorectal and gastric carcinoma patients with TN test reports. We identified chemotherapy regimens given for stage IV disease for which TN reports indicated prediction. Protocols were classified as having clinical benefit (CB; i.e., stable disease or any objective response) or progressive disease, and this was compared with the TN prediction. 

Results: Nineteen patients – 12 colorectal and 7 gastric carcinomas – met the inclusion criteria. There were 26 evaluable treatment protocols; of 18 with a CB 15 were predicted to have a CB while 3 were predicted to have a lack of CB. Of eight protocols that had no CB, seven were predicted to have a CB and one was predicted to have a lack of CB. A chi-square test was non-significant (P = 0.78). An exploratory analysis yielded a positive predictive value of 68% and a sensitivity of 83% for the TN test. 

Conclusions: This study emphasizes the need for larger multicenter studies to validate the TN test before it is adopted into clinical practice. 

 

Background: Diabetes mellitus (DM) is a metabolic sequel in people infected with HIV, especially following the advent of HAART. This may be a particular concern in immigrants due to lifestyle changes. 

Objectives: To characterize the prevalence of DM in HIV-infected Ethiopians in Israel, and to define the risk factors.

Methods: We retrospectively screened the records of 173 HIV-infected Ethiopians and 69 HIV-infected non-Ethiopian HIV patients currently registered at the HIV Clinic of Meir Medical Center. Data were also retrieved from 1323 non-HIV Ethiopians treated in the hospital between 2007 and 2012. The presence of DM was determined by family physician diagnosis as recorded in the hospital database or by the presence of one or more of the following: fasting glucose > 127 mg/dl, hA1C > 6.5% (> 48 mmol/mol), or blood glucose > 200 mg/dl. Population data and risk factors for DM were analyzed by univariate and multivariate analyses. 

Results: Among HIV-infected Ethiopian subjects, the prevalence of DM was 31% (54/173) compared to 4% (3/69) in HIV-infected non-Ethiopians and 8% (102/1323) in non-HIV-infected Ethiopians (P < 0.0001). The relatively increased prevalence of DM was age independent, but most noticeable in those under the median age (< 42 years). Body mass index (BMI) was a predictor for DM (OR 1.263, CI 1.104–1.444, P = 0.001), although its values did not vary between the two ethnic groups. 

Conclusions: HIV-infected Ethiopians are more likely to develop DM at low BMI values compared to non-Ethiopians. This observation questions the relevance of accepted BMI values in this population and suggests that preventive measures against DM be routinely taken in these subjects. 

 

Background: Approximately 80% of patients with myelodysplastic syndromes (MDS) receive multiple red blood cells (RBC), often multiple transfusions, and are therefore prone to develop alloantibodies against RBC. Because of increasing evidence for the role of immune dysregulation in the pathobiology of MDS, we hypothesized that in patients with MDS there is an increase in alloantibody formation beyond that expected by multiple transfusions.

Objectives: To determine the prevalence rates of alloantibodies in patients with MDS who are transfusion dependent and compare them to those of non-MDS patients matched for number of RBC units they received. 

Methods: The blood bank database was screened to identify non-MDS patients matched for age and number of units transfused. Logistic regression analysis was applied to determine factors affecting alloantibody formation. 

Results: Of 60 patients with MDS, 18 (30%) developed alloantibodies against RBC. Transfusion-dependent MDS and non-MDS patients (N=56 each), matched for number of RBC units and age, were compared. Fifteen MDS patients (27%) but only 12 non-MDS patients (12%) developed alloantibodies (P = 0.057). The relative risk for developing antibodies in MDS patients was 2.14, and MDS was the strongest predictor for formation of alloantibodies during transfusion therapy (odds ratio 3.66, confidence interval 1.4–9.3). 

Conclusions: Patients with MDS are at increased risk to develop RBC alloantibodies, partly because these patients receive multiple RBC transfusions. Whether matching for RH and KEL would lead to lower rates of RBC alloantibodies remains to be determined.

 

Background: Exposure to air pollution in the form of particulate matter smaller than 10 µm in diameter (PM10) has been associated with increased morbidity and mortality. However, since air pollution is correlated with confounding factors that might otherwise affect health, identifying the causal link has proven challenging. 

Objectives: To identify the effect of PM10 on hospital admissions due to respiratory illnesses. 

Methods: We used the Instrumental Variable (IV) methodology to control for confounding factors affecting hospital admissions. Exploiting the timing of sandstorms as an instrumental variable allows for a better estimate of the relationship between PM10 and hospital admissions. Data on PM concentrations and hospital admissions rates were compiled for Israel’s two largest cities, Jerusalem and Tel Aviv, for 2007–2009. We compared our IV estimates to those derived from a Poisson regression, which is commonly used in the existing literature. 

Results: Sandstorms led to an increase of 307 µg/m3 of PM10 concentrations. A 10 µg/m3 increase in PM10 is associated with a 0.8% increase in hospital admissions due to respiratory conditions, using Poisson regression. The same finding was noted using the IV methodology. 

Conclusions: The association between PM10 and hospital admission reflects a primarily causal relationship. Instrumental variable methodology could be applied to analysis of the effect of air pollution on hospital admissions. 

 

Background: Extracorporeal membrane oxygenation (ECMO) may serve as a bridge to regain cardiac function in refractory resuscitation. However, its use has so far been limited owing to low availability, especially in emergency departments. 

Objectives: To describe two children with acute myocarditis successfully treated with ECMO in the emergency department of a tertiary pediatric medical center. 

Description: The children presented with vomiting, followed by rapid deterioration to cardiogenic shock that failed to respond to conservative treatment. Given the urgency of their condition and its presumably reversible (viral) etiology, treatment with ECMO was initiated in the department’s resuscitation room. 

Results: Outcome was excellent, and cardiac function remained normal throughout 6 and 10 months follow-up. 

Conclusions: Extracorporeal life support has enormous potential in the emergency department and warrants further assessment.  

Background: In recent years several reports have been published describing dogs’ ability to detect, by scent, patients with cancer. This ability is based on the sniffing of volatile organic elements that are secreted by malignant cells, react to them. 

Objectives: To evaluate the ability of trained dogs to detect (i) breast cancer cell cultures (MCF7) compared to the control pseudo-normal keratinocyte cell line (HaCaT), and then (ii) melanoma (BG) and (iii) type 2 epithelial lung carcinoma (A549) malignant cell cultures to which they were not previously exposed in the course of their training.

Methods: Cell cultures were prepared in a standard manner. Two Belgian Shepherd dogs were trained and then tested in a single-blind test (for dogs and trainers) on their ability to detect the "target specimen," a MCF7 breast cancer cell culture. Following this, the ability of the dogs to detect cancer cell cultures that they were not previously exposed to (i.e., A549, BG) was tested. In each test round, four specimens placed in identical blocks were arranged in a line with one meter between them: one target specimen (MCF7, A549, BG), two control specimens (HaCaT), and a sample containing cell culture medium only.

Results: The two dogs picked out all the target specimens of MCF7 breast cancer cell cultures that they were trained to detect (10/10) as well as all the target specimens that they were not previously exposed to [A549 (5/5) and BG (5/5)], but did not pick out the control specimens or the cell culture medium. Thus, the sensitivity, specificity, and positive and negative predictive values for both dogs were 100%.

Conclusions: The results of this study support the assumption that cancer cells have a unique odor pattern, and that this odor pattern is common to different types of cancer.

 

Background: Several studies have identified associations between low vitamin D concentrations and risk of upper respiratory infections (URI). T lymphocytes have a major anti-viral role, are affected by vitamin D metabolism, and may mediate the link between vitamin D and URIs. Competitive swimmers have a relatively high rate of URIs, alongside a high prevalence of low vitamin D concentration. 

Objectives: To examine the associations linking T cell receptor excision circles (TREC, markers of thymus activity), circulating 25(OH)D concentrations and the effect of vitamin D supplementation, and URI symptoms in young competitive swimmers.

Methods: We tested 82 adolescent swimmers for serum 25(OH)D and TREC concentrations and found that 55 had vitamin D insufficiency. Randomized supplementation of either vitamin D3 or placebo was given for 12 winter weeks. URI symptoms were recorded weekly. The associations between TREC copy numbers, vitamin D and URI burden were examined.

Results: TREC concentrations decreased with the participants’ age (r = -0.346, P = 0.003), with no significant between-gender difference. TREC concentrations did not materially differ among subjects with normal, insufficient or deficient vitamin D status, and were not affected by vitamin D supplementation. No significant correlations were found between TREC levels or their changes during the study period, and mean URI severity or duration. 

Conclusions: Thymus activity, represented by higher TREC levels, was not related to vitamin D concentrations or status, and was not affected by vitamin D supplementation in adolescent swimmers. TREC concentrations were not associated with URI severity or duration in this population.

 

Background: Isolation of methicillin-resistant Staphylococcus aureus (MRSA) in healthy individuals is not common in Israel. In our hospital, about 30% of MRSA isolates were SCCmec types IV and V.

Objectives: To identify the demographic and clinical characteristics of patients carrying MRSA SCCmec type IV or V, and to compare them with each other and with those of patients with SCCmec types I-III.

Methods: We conducted a case-control study that included 501 patients from whom MRSA was isolated: 254 with SCCmec type I, II, or III, and 243 isolates from SCCmec types IV or V. 

Results: MRSA was isolated from surveillance cultures in 75% of patients and from a clinical site in 25%. The majority of our study population was elderly, from nursing homes, and with extensive exposure to health care. First, we compared characteristics of patients identified through screening. Statistically significant predictors of SCCmec V vs. IV were Arab ethnicity (OR 7.44, 95%CI 1.5–37.9) and hospitalization in the year prior to study inclusion (OR 5.7, 95%CI 1.9–16.9). No differences were found between patients with SCCmec types I-III and patients with SCCmec type IV or V. Analysis of the subset of patients who had clinical cultures yielded similar results. 

Conclusions: SCCmec types IV and V were common in the hospital setting although rare in the community. It seems that in Israel, SCCmec IV and V are predominantly health care-associated MRSA. 

 

Background: Anemia confers an adverse prognosis in patients with ST-elevation myocardial infarction (STEMI). Several mechanisms have been implicated in the etiology of anemia in this setting, including inflammation, blood loss, and the presence of comorbidities such as renal failure.

Objectives: To evaluate the adequacy of bone marrow response as potentially reflected by elevation in blood and reticulocyte counts.

Methods: Consecutive men with STEMI who underwent primary percutaneous intervention within 6 hours of symptom onset and who presented to our catheterization laboratory during a 36 month period were included in the study. The cohort was divided into quartiles according to hemoglobin concentration, and differences in clinical and laboratory characteristics between the groups were evaluated.

Results: A total of 258 men with STEMI were recruited, 22% of whom suffered from anemia according to the World Health Organization classification (hemoglobin < 13 g/dl). Men in the lowest quartile of hemoglobin concentration presented with significantly lower white blood cell and platelet counts (9.6 ± 2.9 vs. 12.6 ± 3.6 x103/µl, P < 0.001) and (231 ± 79 vs. 263 ± 8 x103/µl, P < 0.01), respectively, despite higher inflammatory biomarkers (C-reactive protein and fibrinogen) compared with patients in the upper hemoglobin concentration quartile. Reticulocyte production index was not significantly higher in anemic patients with a value of 1.8, 1.4, 1.5 and 1.6 in the ascending hemoglobin quartiles, respectively (P = 0.292). 

Conclusions: Anemic men with STEMI have relatively lower leukocyte and platelet counts as well as a reduced reticulocyte count despite higher inflammatory biomarkers. These findings might suggest inadequate bone marrow response.