Improved sensitivity of an interferon-gamma release assay (T-SPOT.TB™) in combination with tuberculin skin test for the diagnosis of latent tuberculosis in the presence of HIV co-infection

Background Interferon-gamma release assays (IGRA) are more specific than the tuberculin skin test (TST) for the diagnosis of Mycobacterium tuberculosis infection. Data on sensitivity are controversial in HIV infection. Methods IGRA (T-SPOT.TB) was performed using lymphocytes stored within 6 months before culture-confirmed tuberculosis was diagnosed in HIV-infected individuals in the Swiss HIV Cohort Study. Results 64 individuals (69% males, 45% of non-white ethnicity, median age 35 years (interquartile range [IQR] 31-42), 28% with prior AIDS) were analysed. Median CD4 cell count was 223 cells/μl (IQR 103-339), HIV-RNA was 4.7 log10 copies/mL (IQR 4.3-5.2). T-SPOT.TB resulted positive in 25 patients (39%), negative in 18 (28%) and indeterminate in 21 (33%), corresponding to a sensitivity of 39% (95% CI 27-51%) if all test results were considered, and 58% (95% CI 43-74%) if indeterminate results were excluded. Sensitivity of IGRA was independent of CD4 cell count (p = 0.698). Among 44 individuals with available TST, 22 (50%) had a positive TST. Agreement between TST and IGRA was 57% (kappa = 0.14, p = 0.177), and in 34% (10/29) both tests were positive. Combining TST and IGRA (at least one test positive) resulted in an improved sensitivity of 67% (95% CI 52-81%). In multivariate analysis, older age was associated with negative results of TST and T-SPOT.TB (OR 3.07, 95% CI 1,22-7.74, p = 0.017, per 10 years older). Conclusions T-SPOT.TB and TST have similar sensitivity to detect latent TB in HIV-infected individuals. Combining TST and IGRA may help clinicians to better select HIV-infected individuals with latent tuberculosis who qualify for preventive treatment.

Active surveillance of antibiotic resistance prevalence in urinary tract and skin infections in the outpatient setting

The aim of the study was to evaluate the need for active surveillance of antibiotic resistance in ambulatory infections. We measured the prevalence of antibiotic resistance in urinary tract infections (UTIs) (n = 1018) and skin infections (n = 213) diagnosed in outpatients between September 2008 and February 2009 in the Canton of Bern, Switzerland. Samples were stratified into 'solicited' (diagnostic work-up for study purpose only) and 'routine' (diagnostic work-up as part of standard care). Susceptibility patterns were compared for 463 Escherichia coli isolates from UTIs (231 solicited; 232 routine) and 87 Staphylococcus aureus isolates from skin infections (35 solicited; 52 routine). Overall, E. coli showed higher susceptibility to ampicillin, amoxicillin-clavulanic acid and norfloxacin in solicited than in routine samples. Among 15-45-year-old patients, susceptibility rates were comparable between solicited and routine samples for all antibiotics except for amoxicillin-clavulanic acid. However, among patients >45 years old, isolates from routine samples showed lower susceptibility to all β-lactams tested and quinolones than those from solicited samples. Extended-spectrum β-lactamase (ESBL)-producing E. coli isolates were rare (solicited, 0.4%; routine, 1.7%; p 0.4). Susceptibility patterns of S. aureus were comparable between solicited and routine samples. Therefore, in the outpatient setting, susceptibility rates for E. coli isolates differ by indication for urinary culture and age. Surveillance based on samples taken during standard care may underestimate susceptibility rates for uncomplicated infections, especially among the elderly. Reports of resistance data should include age stratification.

[Coumarin-induced necrotic purpura of the skin -- case report and review of the literature]

We report the case of a 28-year old woman with extensive red-black colored lesions of the skin on the left thigh, which appeared without trauma. The disease arrived during longterm coumarin therapy because of a deep vein thrombosis and an antiphospholipid syndrome. After consideration of the differential diagnoses and due to the typical clinical picture we made the diagnosis of coumarin necrosis. We review the clinical and therapeutic features for this rare complication.

Preferential recruitment of bone marrow-derived cells to rat palatal wounds but not to skin wounds

To investigate the contribution of bone marrow-derived cells to oral mucosa wounds and skin wounds.

Diffusion-weighted MR imaging including bi-exponential fitting for the detection of recurrent or residual tumour after (chemo)radiotherapy for laryngeal and hypopharyngeal cancers

To assess whether diffusion-weighted magnetic resonance imaging (DW-MRI) including bi-exponential fitting helps to detect residual/recurrent tumours after (chemo)radiotherapy of laryngeal and hypopharyngeal carcinoma.