The Impact of Borderline Quantiferon-TB Gold Plus Results for Latent Tuberculosis Screening under Routine Conditions in a Low-Endemicity Setting.

Quantiferon-TB Gold Plus (QFT-Plus) is an interferon gamma release assay used to diagnose latent tuberculosis (LTB). A borderline range (0.20 to 0.99 IU/ml) around the cutoff (0.35 IU/ml) has been suggested for the earlier QFT version. Our aims were to evaluate the borderline range for QFT-Plus and the contribution of the new TB2 antigen tube. QFT-Plus results were collected from clinical laboratories in Sweden and linked to incident active TB within 3 to 24 months using the national TB registry. Among QFT-Plus results from 58,539 patients, 83% were negative (<0.20 IU/ml), 2.4% were borderline negative (0.20 to 0.34 IU/ml), 3.4% were borderline positive (0.35 to 0.99 IU/ml), 9.6% were positive (≥1.0 IU/ml), and 1.6% were indeterminate. Follow-up tests after initial borderline results were negative (<0.20 IU/ml) in 38.3%, without any cases of incident active TB within 2 years. Applying the 0.35-IU/ml cutoff, 1.5% of TB1 and TB2 results were discrepant, of which 52% were within the borderline range. A TB2 result of ≥0.35 IU/ml with a TB1 result of <0.20 IU/ml was found in 0.4% (231/58,539) of all included baseline QFT-Plus test results, including 1.8% (1/55) of incident TB cases. A borderline range for QFT-Plus is clinically useful as more than one-third of those with borderline results are convincingly negative upon retesting, without developing incident active TB. The TB2 tube contribution to LTB diagnosis appears limited.

Pattern of morbidity and mortality in Karbala hospitals during Ashura mass gathering at Karbala, Iraq, 2010.

Religious mass gatherings are increasingly common in Iraq and can harbour considerable public health risks. This study was aimed at determining morbidity and mortality patterns in hospitals in Karbala city, Iraq during the mass gathering for Ashura in 2010. We conducted a cross-sectional study on attendees at the 3 public hospitals in the city. The study period was divided into pre-event, event, and post-event phases. Morbidity and mortality data were obtained from hospital registry books and the coroner's office. About 80% of the 18 415 consultations were at emergency rooms. Average daily emergency room attendance was higher during the event compared with pre- and post-event phases, while average daily admissions decreased. Compared with the pre-event phase, a 7-fold increase in febrile disorders and a 2-fold increase in chronic diseases and injuries were noted during the event phase. There was no difference between the 3 phases for average daily death rate, nor for cause of death.