Functional study of lipids of PNH red cell membranes: susceptibility of liposomes to reactive lysis

Lipids extracted with chloroform-methanol from red blood cell membranes of 7 PNH and 13 control subjects were used for the preparation of liposomes, which were then examined with the reactive lysis test. PNH liposomes lysed to a higher extent than control liposomes as indicated by the higher dilution of the limiting complement reagent that was necessary to lyse 50% of the PNH liposomes. A similar finding was also observed with liposomes made of lipids from AET-treated red cells. The enhanced reactive lysis can be attributed to the polar lipid fraction, as indicated by the increased lysis of hybrid liposomes prepared from this polar lipids extracted from PNH erythrocyte membrane and lipids extracted from normal erythrocyte membrane. The increased susceptibility to reactive lysis does not seem to be specific of PNH liposomes, since it was also observed with liposomes prepared from lipids of red cells from beta-thalassemia major and autoimmune hemolytic disease.     

Use of high-sensitivity digital ELISA improves the diagnostic performance of circulating brain-specific proteins for detection of traumatic brain injury during triage

ABSTRACT

Background: Historically, limited sensitivity associated with traditional immunoassay methods has prevented the use of brain-specific proteins as blood biomarkers of traumatic brain injury (TBI) during triage, as these proteins exhibit low circulating concentrations. Digital ELISA is a newly-developed technique that is up to 1000 times more sensitive than conventional ELISA methods. The purpose of this study was to determine whether the use of digital ELISA over conventional ELISA improves the performance of brain-specific proteins as blood biomarkers of TBI during triage.

Methods: Blood was sampled from TBI patients (n = 13) at emergency department admission, as well as from neurologically normal controls (n = 72). Serum levels of two brain-specific proteins, neurofilament light chain (NfL) and Tau, were measured via digital ELISA. Estimated conventional ELISA measures were generated by adjusting values according to the lower limits of detection achievable with commercially available conventional ELISA assays, and receiver operating characteristic (ROC) analysis was used to compare the diagnostic performance of digital ELISA measures to estimated conventional ELISA measures in terms of their ability to discriminate between TBI patients and controls.

Results: Used in combination, digital ELISA measures of NfL and Tau could discriminate between groups with 100% sensitivity and 91.7% specificity. Estimated conventional ELISA measures could only discriminate between groups with 7.7% sensitivity and 94.4% specificity. This difference in diagnostic performance was statistically significant when comparing areas under ROC curves.

Conclusions: The use of digital ELISA over conventional ELISA methods improves the diagnostic performance of circulating brain-specific proteins for detection of TBI during triage.     

Bariatric surgery is safe and effective in Medicare patients regardless of age: an analysis of primary gastric bypass and sleeve gastrectomy outcomes

BackgroundNumerous studies have shown that bariatric surgery in older patients is safe and effective. However, both the Agency for Healthcare Research and Quality (AHRQ) and a Medicare Evidence Advisory Committee (MEDCAC) have cited gaps in the evidence for outcomes in Medicare patients undergoing bariatric surgery. These gaps are predominantly in the safety and outcomes evidence in Medicare patients younger than 65 years old (Centers for Medicare and Medicaid Services [CMS] < 65).ObjectivesThe aim of our study was to review both the safety and efficacy of gastric bypass (RYGB) and sleeve gastrectomy (SG) in Medicare patients compared with other payers.SettingA single academic medical center.MethodsA prospectively maintained database of 3300 patients who underwent bariatric surgery between January 2007 and December 2017 was utilized. The outcomes of Medicare patients undergoing RYGB and SG were analyzed and compared to those of similar patients covered by Medicaid or Commercial insurers.ResultsThere were too few patients with commercial insurance older than 65 to compare to those with Medicare (CMS ≥ 65). Mortality at 90 days for CMS ≥ 65 was 1.3% and the overall complication rate was 20.1% (minor 15.6%; major 7.1%). Total weight loss (TWL) at 6 months and 1, 2, and 3 years was 25.3%, 30.0%, 29.9%, and 29.4% respectively. For any time after surgery, 23% of CMS ≥ 65 had complete remission of diabetes and 45% had partial remission.Demographic analysis of CMS < 65 found Medicare patients were significantly older with more diabetes, hypertension and hyperlipidemia than those with commercial payers. Mortality at 90 days for CMS < 65 was 0.6% and the overall complication rate was 18.3% (minor 14.3%; major 4.7%). Mortality was not significantly different between payers. After adjustment for baseline differences and comparing to the Medicare group, the commercial group was less likely to have minor complications (P = .019), any complications (P = .007), and extended length of stay (P < .001). The TWL for the entire cohort age <65 at 6 months and 1, 2, and 3 years was 28.1%, 34.1%, 34.1%, and 31.8% respectively. After adjusting for differences, there was no significant difference in TWL between payers. For any time after surgery, complete remission of diabetes was 45% in CMS < 65 patients and partial remission was 59%. The comparison of remission between groups was then adjusted for DiaRem score and surgery type. CMS < 65 patients had significantly less partial remission of diabetes than commercial patients (P = .034) but no difference in complete remission.ConclusionsRYGB and SG are both safe and effective in Medicare patients of all ages. CMS ≥ 65 have acceptable mortality and complication rates with TWL and diabetes remission similar to younger patients. CMS < 65 patients are older than those with commercial insurance with more comorbid disease. While they have longer hospital stays after bariatric surgery, their weight loss and complete remission of diabetes are no different than patients with Medicaid or commercial insurance. This study helps fill an important evidence gap in bariatric surgical patients raised by both Agency for Healthcare Research and Quality, and a Medicare Evidence Advisory Committee.     

Medical action for global security (MEDACT): Founding statement

Two principles should underpin the provision of primary health care to refugees: (a) that refugees should have the same access to quality primary care services as the local population, and (b) any specialist service should have the goal of full integration of the refugee into normal general practice. The various ways in which medical care can be provided to refugees and the knowledge, skills and attitudes important to such provision are described. One way in which such a service was provided in east Kent is reported. The term ‘refugee’ encompasses newly arrived refugees who are awaiting a decision from the Home Office, as well as those who have been given permission to stay, either as recognized Refugees under the provisions of the 1951 United Nations Convention, or with Exceptional or Indefinite Leave to Remain.     

Acute renal failure in a neonate due to pelviureteric candidal bezoars successfully treated with long-term systemic fluconazole

Systemic candidiasis with renal involvement is a rare but well-recognized complication during intensive care treatment in very-low-birth-weight infants. We report a term neonate who developed anuria associated with bilateral bezoar formation in the renal pelvis and candidemia. The treatment consisted of placement of a nephrostomy tube in the left kidney, short-term irrigation with amphotericin B and iv, and later, oral administration of fluconazole.