Cumulative False-Positive QuantiFERON-TB Interferon-γ Release Assay Results.

Rationale: Despite reports of unreliability, the QuantiFERON-TB interferon-γ release assay is increasingly used for the annual screening of individuals at risk for latent tuberculosis. Continued use of the QuantiFERON-TB assay suggests the need for more definitive evidence of its reproducibility and accuracy.

Objectives: To examine reproducibility and the accumulation of false-positive test results when the QuantiFERON-TB is repeated annually and to examine the validity of confirming positive test results with the performance of a second QuantiFERON-TB.

A comparison of random and post-accident urine opiate and opioid tests.

Opioid use is associated with poor reaction time, attention, balance and memory posing a potential threat to workplace safety. The purpose of this study is to determine if there is a statistical association between opiate/opioid use and work related accidents as measured by urine drug tests by comparing the proportion of opiate/opioid laboratory positive urine specimens for postaccident verses random samples. The prevalence of laboratory positive opiate/opioid tests, the odds ratio, Fisher's exact probability test and the population attributable risk were calculated for each comparison.

A trend analysis of laboratory positive propoxyphene workplace urine drug screens before and after the product recall.

Background: Propoxyphene was withdrawn from the US market in November 2010. This drug is still tested for in the workplace as part of expanded panel nonregulated testing.

Methods: A convenience sample of urine specimens (n = 7838) were provided by workers from various industries.

Respiratory hospitalizations of children living near a hazardous industrial site adjusted for prevalent dust: a case-control study.

The Neot Hovav Industrial Park (IP), located in southern Israel, hosts 23 chemical industry facilities and the national site for treatment of hazardous waste. Yet, information about its impact on the health of local population has been mostly ecological, focused on Bedouins and did not control for possible confounding effect of prevalent dust storms. This case-control study examined whether living near the IP could lead to increased risk of pediatric hospitalization for respiratory diseases.

Marijuana and workplace safety: an examination of urine drug tests.

Although the decriminalization of recreational marijuana and medical marijuana laws provide a compassionate answer for treatment-related issues in patients' lives, they leave questions open as to the impact on other realms of life, such as employment and safety. This is a case-control study comparing the proportion of marijuana positive urine specimens for post-accident verses random samples. The marijuana concentration of each sample underwent creatinine normalization to account for in vivo dilution.

Dilution of urine drug tests: is it random?

Background: The purpose of this study was to determine whether the act of in vivo urine dilution is a random phenomenon.

Methods: The sample population was divided into 4 groups for each of the drugs tested. The groups are precreatinine normalization laboratory positive, precreatinine normalization laboratory negative, and postcreatinine normalization laboratory drug positive, and postcreatinine normalization laboratory drug negative.

Creatinine normalization of workplace urine drug tests: does it make a difference?

Background: This study examines the effect of creatinine normalization on urine drug concentrations of 5 substances (amphetamines, cocaine, marijuana, opiates, and phencyclidine) and how this affects the proportion of reported positives.

Methods: The Wilcoxon matched-pairs signed-ranks test was used to compare the mean prenormalization urinary drug concentration with the mean postnormalization urinary drug concentration. Frequency analysis was performed on dichotomous drug test results and the information was used to complete McNemar testing for each drug to determine the difference of proportions for prenormalization positive drug tests to postnormalization positive drug test.

Comparison of random and postaccident urine drug tests in southern Indiana coal miners.

Background: This study examines the relationship between the use of 9 classes of substances (amphetamines, barbiturates, benzodiazepines, cocaine, marijuana, methadone, opioids, phencyclidine, and propoxyphene) and coal-mining accidents.

Methods: The control sample (n = 215) made up of miners that presented for random urine drug testing. The study sample (n = 100) consists of miners that presented for postaccident urine drug testing.

Elevated chromium levels and prosthetic joint implants.

Chromium is a naturally occurring, toxic heavy metal used in many industrial processes. The U.S.

Pleural plaques related to "take-home" exposure to asbestos: An international case series.

Context: While a large number of studies indicate the risks of high-level exposures to asbestos in the workplace setting, a relatively small number of studies describe the risk of pleural disease related to "take-home" asbestos brought into the household by workers exposed to asbestos. Consequently, the risk of pleural disease in family members of asbestos-exposed workers is likely underappreciated.

Case Presentations: Two families of siblings, one in Israel and one in the US, were evaluated because of their significant exposures to asbestos brought into the home by family members with heavy occupational exposures.

Durability of vaccinia immunization based on reaction at the rechallenge site.

The authors reviewed the immunization records of 621 patients who received vaccinia vaccination in our Occupational Medicine Clinic between July 26, 1994 and October 11, 2001 to evaluate the durability of the vaccine over time, as judged by the patients' local skin reactions following revaccination. Results of the study document a waning immunity to vaccinia immunization in the majority of re-vaccinees. Over 63.

Reactive airways dysfunction syndrome following exposure to a fluorocarbon.

This report describes the case of a 43-yr-old male who developed reactive airways dysfunction syndrome after exposure to a high level of bromotrifluoromethane (CF3Br, Halon 1301), a fluorocarbon widely used in automatic fire extinguishing systems. The patient was a previously healthy, nonatopic male, who developed wheezing and intermittent and reversible obstructive ventilatory impairment starting immediately after a large accidental nonfire-related release of CF3Br in a confined space.

Diagnosis of malignant pleural mesothelioma by supraclavicular lymph node biopsy.

Extrathoracic lymph node metastases in pleural mesothelioma are rare. A case of pleural mesothelioma diagnosed by supraclavicular lymph node biopsy is described. To our knowledge, this is the first reported case of pleural mesothelioma diagnosed in this manner.