Non-randomized studies should be considered for assessing surgical techniques in rectal prolapse: prospective cohort study.

AIM: Randomized trials comparing surgical techniques for rectal prolapse are not always feasible. We assessed whether non-randomized comparisons of those who have had surgery with those still waiting would be confounding baseline health status. METHOD: This was a prospective cohort study in seven UK hospitals. Participants were ≥ 18 years and listed for surgical interventions of equivalent intensity for rectal prolapse. They were defined as short or long waiters (≤ 18 or > 18 weeks, respectively). Time on the waiting list was compared with baseline comorbidity (Charlson comorbidity index) and change from baseline in health status (EQ-5D-5L) at the time of surgery. RESULTS: In all, 203 patients were analysed. Median (interquartile range) waiting time was 13.7 weeks (8.1, 20.4) varying across sites. Baseline comorbidity was not an important predictor of waiting time. Median Charlson comorbidity index was 2 (0, 3) for short and 1 (0, 3) for long waiters. A change in waiting time by a week was associated with negligible improvement in the EQ-5D-5L index of 0.001 (95% CI -0.000 to 0.003, P = 0.106). CONCLUSION: Negligible change in patient reported health status while on the waiting list and lack of effect of comorbidities in influencing waiting time support the use of non-randomized pre-/post-studies to compare the effects of surgical interventions for rectal prolapse.

Risk factors for mortality in smear-negative tuberculosis suspects: a cohort study in Harare, Zimbabwe.

OBJECTIVE: To investigate mortality rates and risk factors for death among smear-negative tuberculosis (TB) suspects. DESIGN: Cohort study nested within a cluster-randomised trial of community-based active case finding. Smear-negative TB suspects were followed for 12 months, with home tracing where necessary. We calculated mortality rates and used regression analysis to investigate the relationship between clinical characteristics and death. RESULTS: Between February 2006 and June 2007, 1195 smear-negative TB suspects were followed for 1136.8 person-years. Human immunodeficiency virus (HIV) prevalence was 63.3%. During follow-up, 139 participants died (11.6%) and mortality rates remained high throughout; 119 (16.5%) HIV-positive individuals and 13 (3.1%) HIV-negative individuals died (HR = 5.8, 95%CI 3.3-10.4, P < 0.001). Advanced immunosuppression was the main risk factor for death among HIV-positive participants, with CD4 count < 50 cells/µ l associated with a 13-fold increased risk of death. Antiretroviral treatment (ART) was initiated by only 106 (14.7%), with long delays in accessing care. CONCLUSION: HIV-positive smear-negative TB suspects are at high and sustained risk of death. Current guidelines for the management of HIV-infected TB suspects are limited, and this study adds to evidence that specific policies are required to promote earlier HIV and TB diagnosis and reduce delays in ART initiation.

Diagnostic accuracy of commercial urinary lipoarabinomannan detection in African tuberculosis suspects and patients.

OBJECTIVE: To evaluate a commercially available antigen capture enzyme-linked immunosorbent assay (ELISA) based on detecting lipoarabinomannan (LAM) in urine for the diagnosis of tuberculosis (TB). DESIGN: Consenting TB suspects and registering TB patients prospectively recruited from three hospitals were asked for two sputum specimens for microscopy and culture, urine for LAM testing and blood for human immunodeficiency virus (HIV) testing, with radiological and clinical follow-up for 2 months. RESULTS: Of 427 participants, complete data were available from 397 (307 adult and 23 adolescent TB suspects, and 67 registering TB patients). HIV prevalence was 77%. TB was diagnosed in 195 (49%), including 161 culture-positive patients, and confidently excluded in 114 (29%) participants. LAM ELISA sensitivity was 44% (95%CI 36-52) for culture-confirmed TB (52% in smear-positive patients). Specificity was 89% (95%CI 81-94). Sensitivity was significantly higher in HIV-related TB (52%, 95%CI 43-62, P < 0.001) compared to HIV-negative TB (21%, 95%CI 9-37). Sensitivity in smear-negative patients was low (28%, 95%CI 13-43) for combined HIV-positive and -negative patients. CONCLUSION: Our findings confirm greater sensitivity of urine LAM detection for HIV-related TB. However, both sensitivity and specificity were suboptimal, suggesting that this version cannot confirm or exclude TB in either HIV-infected or non-infected patients.