Loss of volunteer blood donors because of unconfirmed enzyme immunoassay screening results. Retrovirus Epidemiology Donor Study

BACKGROUND: Blood donors who test repeatably reactive on enzyme immunoassay (EIA) and are not confirmed as positive are a continuing problem for blood banks. Units are discarded and donors are deferred, in spite of multiple studies indicating that such donors are very rarely infected with the transmissible agents. Few data are available, however, with which to evaluate whether the discarded units are more likely to come from particular demographic subgroups. STUDY DESIGN AND METHODS: The Retrovirus Epidemiology Donor Study database of over 2 million allogeneic whole-blood donations collected in the years 1991 through 1993 was utilized. The prevalence of false-positive and indeterminate test results within demographic subgroups was computed for antibodies to human immunodeficiency virus, hepatitis C virus, and human T-lymphotropic virus (anti-HIV, anti-HCV, anti-HTLV, respectively) and hepatitis B surface antigen (false-positive only) as the proportion of donations that were repeatably reactive on EIA but negative or indeterminate on the confirmatory or supplemental test. RESULTS: Several demographic groups with increased prevalence of false- positive and indeterminate anti-HIV results were the same females, younger age groups, blacks, and first-time donors. Likewise, many of the demographic subgroups with increased prevalence of false-positive and indeterminate anti-HCV results were similar: older age groups, non- whites, lower education levels, first-time donors, donors making directed donations, and donors who had received transfusions. For anti- HTLV, by contrast, the oldest group had the highest prevalence of false- positive results but the lowest prevalence of indeterminate results: blacks had the lowest prevalence of false positive results but the highest prevalence of indeterminate results. CONCLUSION: If units that test repeatably reactive on EIA but that are not confirmed as positive are almost always from individuals not infected with the virus in question, then these results indicate that there may be sex-, race-, and/or age-linked proteins cross-reacting with the test kit materials. Elucidation of these antigenic determinates and their subsequent removal should be a priority.     

Heart rate variability and implication for sport concussion

Finding sensitive and specific markers for sports‐related concussion is both challenging and clinically important. Such biomarkers might be helpful in the management of patients with concussion (i.e. diagnosis, monitoring and risk prediction). Among many parameters, blood flow–pressure metrics and heart rate variability (HRV) have been used to gauge concussion outcomes. Reports on the relation between HRV and both acute and prolonged concussion recovery are conflicting. While some authors report on differences in the low‐frequency (LF) component of HRV during postural manipulations and postexercise conditions, others observe no significant differences in various HRV measures. Despite the early success of using the HRV LF for concussion recovery, the interpretation of the LF is debated. Recent research suggests the LF power is a net effect of several intrinsic modulatory factors from both sympathetic and parasympathetic branches of the autonomic nervous system, vagally mediated baroreflex and even some respiratory influences at lower respiratory rate. There are only a few well‐controlled concussion studies that specifically examine the contribution of the autonomic nervous system branches with HRV for concussion management. This study reviews the most recent HRV– concussion literature and the underlying HRV physiology. It also highlights cerebral blood flow studies related to concussion and the importance of multimodal assessment of various biological signals. It is hoped that a better understanding of the physiology behind HRV might generate cost‐effective, repeatable and reliable protocols, all of which will improve the interpretation of HRV throughout concussion recovery.     

Long-term therapy for pulmonary hypertension in children

This review recounts recent advances in the understanding and treatment of the processes that cause pulmonary hypertension in infancy and childhood. New discoveries have begun to unveil connections between the basic physiological mechanisms responsible for the regulation of pulmonary vascular tone and the abnormal responses of the pulmonary vasculature in a variety of disease conditions. These discoveries raise hope for new therapeutic interventions that may improve the high mortality and morbidity of both children and adults with pulmonary vascular disease. In the meantime, treatment efforts continue to be focused on the relief of pulmonary vasoconstriction with inhaled nitric oxide and intravenous prostacyclin in the short term and oral calcium channel blockers as the mainstay of long-term therapy. Lung transplantation often remains as the only viable option for continued survival when the pulmonary vascular disease is progressive.     

A Desmoid Tumor-Staging System Separates Patients with Intra-Abdominal,Familial Adenomatous Polyposis-Associated Desmoid Disease by Behavior and Prognosis

Purpose  Intra-abdominal desmoid tumors associated with familial adenomatous polyposis are heterogeneous. A recent staging system categorizes desmoids according to size, symptoms, and complications. We applied the staging system to determine whether it separates patients into clinically significant groups. Methods  The staging system was applied to 101 patients with familial adenomatous polyposis. Results  There were 21 patients with Stage I tumors, 36 with Stage II, 26 with Stage III, and 18 with Stage IV. Twelve patients with Stage I and five with Stage II tumors needed no treatment. Eight patients with Stage I disease received medical treatment, as did 26 with Stage II, 16 with Stage III, and 15 with Stage IV. Six Stage I tumors had surgery, as did 20 Stage II, 12 Stage III, and 13 Stage IV. Chemotherapy was given to 1 Stage II tumor, 7 Stage III, and 5 Stage IV. No patient with Stages I or II disease died. Four Stage III patients (15 percent) and 8 Stage IV patients (44 percent) died from desmoids. Finally 89 percent with Stage I, 65 percent with Stage II, 59 percent with Stage III, and 50 percent with Stage IV disease were asymptomatic; 81 percent of Stage I desmoids, 78 percent of Stage II, 42 percent of Stage III, and 28 percent of Stage IV were stable or disappeared. Conclusion  Desmoid staging identifies tumors by prognosis and its use for designing prospective treatment studies is reasonable. Read meeting of The American Society of Colon and Rectal Surgeons, Philadelphia, Pennsylvania, April 30 to May 5, 2005. Reprints are not available.     

Financial Incentives for Pediatric HIV Testing (FIT): Caregiver Insights on Incentive Mechanisms,Focus Populations,and Acceptability for Programmatic Scale Up

AIDS and Behavior - Children living with HIV experience gaps in HIV testing globally; scaling up evidence-based testing strategies is critical for preventing HIV-related mortality. Financial...     

Renal cell carcinoma: dynamic thin-section CT assessment of vascular invasion and tumor vascularity

Dynamic thin-section computed tomography (CT) was used to evaluate renal cell carcinoma in 80 patients. The lesion was correctly staged with CT in 90% of patients. With use of the dynamic technique, the ipsilateral renal vein was depicted in 99% of patients. Extension of the tumor to the renal vein or the inferior vena cava was correctly detected in 18 of 19 patients. Actual depiction of tumor thrombus was a far more accurate indicator of renal vein invasion than was the identification of isolated renal vein enlargement. Dynamic thin-section CT of the kidney should be considered the routine method for comparison studies with other newer cross-sectional techniques in the evaluation of renal cell carcinoma.     

Intraocular tumors: evaluation with MR imaging

Sixty-seven ocular tumors were studied with magnetic resonance (MR) imaging and computed tomography (CT). These tumors included primary uveal melanoma (n = 55), circumscribed choroidal hemangioma (n = 3), diffuse choroidal hemangioma (n = 1), retinal capillary hemangioma (n = 1), medulloepithelioma (n = 1), choroidal nevus (n = 1), retinoblastoma (n = 1), and choroidal metastases (n = 4). MR imaging demonstrated all these lesions, while CT demonstrated 88%. Associated retinal detachment was more easily distinguished from the neoplasms with MR imaging. Extrascleral extension of melanoma and hemorrhagic cystic necrosis within the melanoma were clearly demonstrated with MR imaging, but not with CT. Ninety-three percent of melanomas were markedly hyperintense, compared with the intensity of the vitreous body, on T1-weighted images and hypointense on T2-weighted images. All metastatic lesions were isointense on T1-weighted images and hypointense on T2-weighted images. The circumscribed choroidal hemangiomas were hyperintense on T1-weighted images and isointense on T2-weighted images. MR imaging is superior to CT in detection of intraocular tumors and may be more specific in diagnosis.