Increased detection of hepatitis C virus infection in commercial plasma donors by a third-generation screening assay

BACKGROUND: Routine screening of blood donations with second-generation hepatitis hepatitis C virus (HCV) assays has substantially reduced the occurrence of posttransfusion hepatitis. However, following the development of third-generation assays, several studies indicated that these assays may identify HCV-infected individuals who are not identified by second-generation assays. STUDY DESIGN AND METHODS: The sensitivity of a third-generation HCV enzyme-linked immunosorbent assay (ELISA-3) was compared with a second-generation ELISA (ELISA-2) in a side-by-side study of 9936 commercial blood donors. ELISA-reactive specimens were subjected to supplemental analysis by third-generation recombinant immunoblot assay and polymerase chain reaction. RESULTS: ELISA-3 demonstrated greater sensitivity than ELISA-2, detecting 1 additional recombinant immunoblot assay-positive specimen per 2000 tested. ELISA-3 also detected 1 additional HCV-infectious polymerase chain reaction-positive unit among approximately 10,000 units screened. CONCLUSION: The incremental sensitivity achieved with ELISA-3 can be expected to eliminate approximately 20 infectious donations per week among those made by commercial donors in the United States. In accordance with previous studies, most of the improved sensitivity of ELISA-3 derives from its increased detection of anti-c33c (NS3), rather than from the inclusion of HCV antigen NS5.     

Livedo reticularis associated with interferon α therapy in two melanoma patients

We report two patients who developed intense livedo reticularis clearly related to the administration of interferon alpha 2b as an adjuvant therapy for melanoma. Histological studies showed scattered perivascular infiltrates without vasculitis. Laboratory tests excluded any underlying condition. Resolution of the symptoms was observed in both patients when interferon alpha was withdrawn. These cases highlight the occurrence of livedo reticularis as an uncommon side-effect of interferon alpha treatment.     

Instrumented measurement of anterior-posterior laxity of the knee joint after tibial plateau fracture

The Knee Signature System (KSS) was used to measure anterior-posterior laxity of the knees of 34 patients who had an old tibial plateau fracture. The mean total tibial translation with respect to the femur was 9.8 (range 3.1–19.5) mm in the injured knees and 7.5 (range 3.1–14.2) mm in the uninjured knees (P < 0.01). A side-to-side difference (injured versus uninjured knee) to 3 mm or more was found in 13 knees (38%). Neither mode of treatment nor extent of residual displacement of the condyles had any correlation with the sagittal translation. Because complete rupture of cruciate ligaments in association with tibial plateau fracture has been proven to be uncommon and changes in bony configuration did not affect the result, the abnormal tibial translation was left to be a consequence of stretching of the ligaments increasing multi-dimensional instability of the knee joint. The phenomenon was found more pronounced in older patients whose tolerance of ligaments and other soft tissues against stretching forces is decreased. Therefore, when using the KSS device, a side-to-side difference of 3 mm or more in sagittal translation of the tibia with respect to the femur is not always an indication of anterior cruciate ligament deficiency, when such differences are found in patients with an old tibial plateau fracture.     

Clinical application of human egg cryopreservation

Clinical egg cryopreservation has been applied during a 4-year period with some limited success. Mostly mature and a few immature eggs were frozen slowly and thawed rapidly in 1,2-propanediol and sucrose, and subsequently inseminated by intracytoplasmic sperm injection (ICSI). Three studies were performed in which: (i) it was established that 55% of aged unfertilized mature eggs survive freezing; (ii) in 22 cycles of thawed donated eggs cryosurvival was 24% with 15 cycles reaching transfer, and five pregnancies were initiated, one of which went to term at 39 weeks with fraternal twin boys, and one remains ongoing at 37 weeks; and (iii) in five cycles, where in-vitro fertilization patients had some of their own eggs frozen/ thawed, cryosurvival of mature eggs was poor at only 2.2%, although 44% sibling germinal vesicle (GV) stage eggs survived. A normal female infant delivered at 40 weeks arose from transfer of two embryos where GV eggs underwent in- vitro maturation post-thaw and were fertilized by ICSI. Pregnancies reported here and by others indicate a burgeoning awareness of the potential benefits of egg cryopreservation, prompting cautious optimism for the future of this technology.      

Plasma and serum micronutrient concentrations in preschool children

Abstract The plasma concentrations of vitamin A, vitamin E, β-carotene and serum concentrations of zinc, retinol-binding protein and prealbumin were examined for a random cluster sample, stratified by socioeconomic status, of 467 healthy preschool children. Children were aged 9–62 months; 44% were females. The mean plasma values were: vitamin A, 1.29 µmol 1^-1; vitamin E, 18.9 µmol 1^-1; and β-carotene, 0.30 µmol 1^-1. The mean serum values were: zinc, 13.9 µmol 1^-1; retinol-binding protein, 25.5mg 1^-1; and prealbumin, 186.2 mg 1^-1. The mean molar ratio of vitamin A to retinol-binding protein for the study group was 1.10. There were no differences in the mean values of any of the measured micronutrients between the genders. The results of this survey do not indicate that the prevalence of micronutrient deficiency in this preschool population is of public health significance.     

An auto-anti-M causing hemolysis in vitro

A 64-year-old white man, who had never received a transfusion, was found to have anti-M in his serum. The antibody agglutinated all M+ red cells in room-temperature tests. When the ionic strength of the test milieu was reduced by use of an additive solution and the tests were incubated at 37 degrees C, the antibody hemolyzed M + N- but not M+N+ red cells. All M+ red cells reacted in indirect antiglobulin tests using polyspecific antiglobulin reagents when such tests followed an initial incubation at room temperature. When red cells and the patient's serum were warmed to 37 degrees C before being mixed, no antibody activity was demonstrable. The antibody was adsorbed to exhaustion onto M+N- and M+N+ red cells (including the patient's own), and its activity was destroyed by dithiothreitol. There was no evidence of in vivo red cell destruction by the autoantibody. No previously reported example of anti-M has been shown to activate complement in conventional in vitro tests. This example was extraordinary in that it caused sufficient complement activation to present as an in vitro hemolysin.     

Evidence that CDw108 membrane protein bears the JMH blood group antigen

BACKGROUND: CDw108 is a cluster-of-differentiation antigen that resides on a glycosylphosphatidylinositol (GPI)-linked protein; it has not previously been shown to be expressed on red cells. JMH is a high- frequency red cell blood group antigen that resides on a GPI-linked protein of molecular weight similar to that bearing CDw108. The purpose of this study was to investigate whether CDw108 is expressed on red cells and whether it resides on the same membrane protein as does JMH. STUDY DESIGN AND METHODS: Murine monoclonal antibodies to CDw108, MEM- 121 and MEM-150, as well as a murine monoclonal antibody and human antibodies to JMH were used in radioimmunoassay, inhibition assay, Western blotting, and monoclonal antibody-specific immobilization of erythrocyte antigen assay. RESULTS: MEM-121 and MEM-150 were found to bind to red cells, and MEM-150 blocked binding of human anti-JMH to red cells. Anti-CDw108 and anti-JMH identified red cell membrane proteins that were of similar size and that were absent from JMH-negative red cells on Western blotting. MEM-150 and MEM-121 also immobilized the same protein that reacted with human anti-JMH. CONCLUSION: CDw108 is expressed on red cells and resides on the same GPI-linked membrane protein as does the JMH blood group antigen.