Standardizing 25-hydroxyvitamin D data from the HunMen cohort.

Standardization of 25-hydroxyvitamin D (25OHD) values is still a challenge. We propose standardization by correction of the measured 25OHD values using the linear regression bias from the National Institute of Standards and Technology (NIST) 'total' target values reported by Vitamin D External Quality Assessment Scheme (DEQAS). Our approach could perhaps be a practical solution to the anomaly surrounding non-standardized 25OHD values. INTRODUCTION: Standardization of 25OHD values is still a challenge. We propose standardization by correction of the measured 25OHD values using the linear regression equation derived from the analysis of relationship between total 25OHD values measured by the methodology used by the laboratory and the NIST total target values (TV) reported by the DEQAS for all 5 of the DEQAS samples in a given survey. METHODS: We applied our approach to standardize total 25OHD values of the HunMen cohort. RESULTS: All 206 samples for the HunMen cohort were evaluated using the automated Liaison DiaSorin total 25OHD chemiluminescence immunoassay (CLIA). The timing of these measurements coincided with that of the October 2015 DEQAS survey using samples 481 to 485. Following standardization, the mean total 25OHD changed from 53 to 62 nmol/L and the prevalence of hypovitaminosis D (<75 nmol/L) decreased significantly from 84 to 72%. CONCLUSION: A simple approach readily applicable at the routine diagnostic laboratory could perhaps be a practical solution to the anomaly surrounding non-standardized 25OHD values.

[Thrombocyte dysfunction in children with albinism]. / Thrombocytafunkció-zavar albínó gyermekekben.

Seven children with albinism were examined for haemorrhagic diathesis. In 6 patients coagulation screening tests (prothrombin time, activated partial thromboplastin time, thrombin time) were normal, in 1 patient prolongation of activated partial thromboplastin time due to mild factor XI deficiency was found. Platelet counts were in the reference range, however, the template bleeding time of 6 out of 7 patients was prolonged. Evaluation of platelet aggregation and secretion in a lumi-aggregometer demonstrated that only the child with normal bleeding time had normal platelet function, and 6 children with prolonged bleeding time had impaired aggregation and release reaction. Five out of these 6 patients had severe decrease of ATP secretion even when high dose of thrombin was used as agonist. The number of dens granules in the platelets of these patients, as measured by the uptake of mepacrine, was significantly less than in normal controls. These findings clearly suggested storage pool deficiency. In one of these patients storage pool deficiency was associated with mild factor XI deficiency. The high frequency of haemorrhagic diathesis in albino children emphasizes, the importance of the screening of patients with albinism for bleeding diathesis.

Syndrome of lymphoedema and distichiasis.

A family of ten members in three generations who were affected by lymphoedema with or without distichiasis (extra rows of eyelashes) was observed. This combination of symptoms can be presumed to represent a rare but well-defined hereditary syndrome transmitted by an autosomal dominant gene. Some years ago the published pedigrees of congenital hereditary lymphoedema were reviewed and analysed genetically by Esterly (1965). Recently papers have been published on the association of lymphostasis with congenital distichiasis (Falls and Kertesz, 1964; Robinow et al., 1970; Jester, 1977). We report here a family with ten members in three generations affected by lymphoedema with or without distichiasis.

[Severe microphthalmus with Patau's syndrome (author's transl)]. / Hochgradiger Mikrophthalmus beim Patau-Syndrom.

The authors describe a new-born child with Patau's syndrome in which D-trisomy was zytogenetically proved. The interest in this case is justified by the fact that an anophthalmos was suspected on clinical examination, but the histological examination showed a severe grade of bulb hypoplasia. The authors stress the significance of chromosome examination in cases of multiple congenital deformities associated with eye changes.