Assessment of differences in HLA-A, -B, and -DRB1 allele mismatches among African-American and non-African-American recipients of deceased kidney transplants.

Among recipients of deceased donor kidney transplants, African-Americans experience a more rapid rate of kidney allograft loss than non-African-Americans. The purpose of this study was to characterize and quantify the HLA-A, -B, and -DRB1 allele mismatches and amino acid substitutions at antigen recognition sites among African-American and non-African-American recipients of deceased donor kidney transplants matched at the antigen level. In recipients with zero HLA antigen mismatches, the degree of one or two HLA allele mismatches for both racial groups combined was 47%, 29%, and 11% at HLA-DRB1, HLA-B, and HLA-A, respectively. There was a greater number of allele mismatches in African-Americans than non-African-Americans at HLA-A (P < .0001), -B (P = .096), and -DRB1 loci (P < .0001). For both racial groups, the HLA allele mismatches were predominantly at A2 for HLA-A; B35 and B44 for HLA-B; but multiple specificities for HLA-DRB1. The observed amino acid mismatches were concentrated at a few functional positions in the antigen binding site of HLA-A and -B and -DRB1 molecules. Future studies are ongoing to assess the impact of these HLA mismatches on kidney allograft loss.

Heart transplant center practice patterns affect access to donors and survival of patients classified as status 1 by the United Network of Organ Sharing.

OBJECTIVE: To determine the effect of adult cardiac transplant center practice patterns within a single organ procurement organization on access to donors and survival for patients listed as United Network of Organ Sharing (UNOS) status 1. METHODS: A total of 662 patients listed (January 1, 1992, through December 31, 1995) as UNOS status 1 for heart transplantation by the 4 adult cardiac transplant centers in an organ procurement organization were analyzed in a retrospective cohort study to determine differences in clinical outcomes. RESULTS: The specific center at which an individual was listed as UNOS status 1 was a significant independent predictor of receiving a transplant (odds ratios for 3 centers vs center with highest likelihood = 0.73, 0.64, 0.35, respectively; P <. 01). Only 1 center had a significantly increased mortality rate compared with the other centers (odds ratio 2.03, P <.01). CONCLUSION: Within a single regional organ procurement organization, cardiac transplant centers demonstrate significant variability in the likelihood of transplantation and survival for patients listed as UNOS status 1.

Centralization of histocompatibility laboratories: impact on organ allocation efficiency and outcomes of cadaveric renal transplantation.

This project was undertaken to determine whether centralization of histocompatibility laboratory services for renal transplants performed within eastern Pennsylvania could improve the efficiency of allograft allocation and short-term allograft function. A nonconcurrent cohort study was performed comparing renal allografts transplanted between September 15, 1993, and September 14, 1994, to those transplanted between September 15, 1994, and September 14, 1995. All allografts were procured and allocated by the Delaware Valley Transplant Program, the organ procurement agency in eastern Pennsylvania. Cold preservation time and delayed allograft function were used to measure efficiency of allograft allocation and short term allograft function, respectively. The mean cold preservation time was reduced from 25.08 hours to 20.68 hours (P < 0.001). The percentage of delayed allograft function was 19.9 and 17.4 for the pre- and postcentralization groups, respectively (P = 0.5). Therefore, centralization of histocompatibility tissue typing was a regionally effective process intervention for reducing cold preservation time without adversely impacting short-term graft function. The magnitude of this reduction varied between individual centers. Further investigation is required to determine the effect on long-term allograft function and system wide costs.

Sialidosis type 1: cherry red spot-myoclonus syndrome with sialidase deficiency and altered electrophoretic mobilities of some enzymes known to be glycoproteins. 1. Clinical findings.

A family is described with three affected brothers, two of whom were examined, born to consanguineous parent, who in early adult life began to experience ataxia, intention myoclonus, and progressive visual failure. The brothers examined had cherry red spots at the maculae and cataracts. They were of normal intelligence. The intention myoclonus responded partially to treatment with clonazepam and pheneturide, but not to 5-hydroxytryptophan in combination with carbidopa or to sodium valproate. Studies in one patient showed the excretion of large quantities of sialylated oligosaccharides in the urine. Both patients showed deficient sialidase activity in their cultured fibroblasts. Further studies on cultured skin fibroblasts revealed increased electrophoretic mobility of six glycoprotein enzymes that was returned approximately to normal by treatment with sialidase. The clinical and biochemical findings indicate that these patients are further cases of the newly described condition sialidosis type 1.

Sialidosis type 1: cherry red spot-myoclonus syndrome with sialidase deficiency and altered electrophoretic mobility of some enzymes known to be glycoproteins. II. Enzymes studies.

Observations have been made on two brothers who had progressive ataxia, intention myoclonus and visual failure starting early in the third decade of life. Their parents were consanguineous. The brothers showed bilateral cherry red spots at the maculae and bilateral perinuclear cataracts; their intelligence was preserved. Urine was found to contain large amounts of sialylated oligosaccharides; cultured skin fibroblasts showed deficiency of the enzyme sialidase (neuraminidase). Studies on leucocytes and cultured skin fibroblasts showed aberrant electrophoretic mobilities of six enzymes all of which are known to be glycoproteins, and this has been attributed to excessive amounts of sialic acid on the enzyme molecules. The clinical features together with the biochemical findings indicate that these are further cases of the newly described condition Sialidosis Type 1 and it is suggested that the electrophoretic findings might be typical of the condition.

An aid to successful probing of the nasolacrimal duct.

An electrical method is described for confirming the entry into the nose of a nasolacrimal probe.