Two samples for blood transfusion: single centre experience.

OBJECTIVES: The aim of this study was to evaluate the introduction of two-sample policy for transfusion at our hospital and reduction of the risk of ABO incompatible transfusion. BACKGROUND: ABO incompatible transfusion can be a fatal but avoidable event. Wrong blood in tube is a cause of ABO incompatible transfusion and there are various strategies available to try and expunge this event. METHODS: Survey of policy/practice before and after the introduction of a two-sample policy. RESULTS: Staff training is inadequate in reducing the risk of ABO incompatible transfusion. A two-sample policy was introduced and does not significantly increase workload or use of group O blood and does not compromise patient safety by causing delay in blood provision. Post hoc analysis confirms good understanding of the policy by medical staff. Observation of medical staff taking transfusion samples demonstrated consistent deviation from policy, enforcing the need for confirmatory samples. CONCLUSION: A two-sample policy adds an extra layer of safety to transfusion practice and can be introduced without creating new problems.

Clinical and molecular characterization of individuals with recurrent genomic disorder at 10q22.3q23.2.

The identification of genomic imbalances in young patients can affect medical management by allowing early intervention for developmental delay and by identifying patients at risk for unexpected medical complications. Using a 105K-feature oligonucleotide array, we identified a 7.25 Mb deletion at 10q22.3q23.2 in six unrelated patients. Deletions of this region have been described in individuals with cognitive and behavioral abnormalities, including autistic features, and may represent a recurring genetic syndrome. All four patients in this study for whom clinical information was available had mild dysmorphic features and three had developmental delay. Of note is the emerging clinical phenotype in these individuals with similar dysmorphic features such as macrocephaly, hypertelorism, and arachnodactyly, and neurodevelopmental delay that includes failure to thrive, hypotonia, and feeding difficulties in the neonatal period, and receptive and expressive language delay with global neurodevelopmental delay after the neonatal period. However, there is no pattern of abnormalities, craniofacial, behavioral, or otherwise, that would have aroused clinical suspicion of a specific syndrome. Finally, the patients' deletions encompass BMPR1A but not PTEN, and these patients may be at risk for colon cancer and should be referred for appropriate prophylactic care and surveillance. Of the two patients in this study who had colonoscopy following the array results, neither had polyps. Therefore, the magnitude of the increased risk for colon cancer is currently unknown.

Congenital chylothorax in neonatal thyrotoxicosis.

We report a patient with congenital chylothorax who also had neonatal thyrotoxicosis secondary to maternal Graves' disease. Fetal tachycardia with hydrops was detected at 28 weeks' gestational age. The fetus responded to antithyroid medication in utero but had persistent bilateral pleural effusion. At birth, he had respiratory distress due to massive pleural effusion. Cytologic studies of pleural fluid were consistent with chylothorax. To the best of our knowledge, the association of congenital chylothorax with fetal (neonatal) thyrotoxicosis, has not been reported previously.

A case of insertional translocation involving chromosomes 2 and 4.

We report on a 6-year-old Caucasian boy with direct insertion of genetic material from the short arm of chromosome 4 to the short arm of chromosome 2. He was referred for evaluation because of global developmental delay and seizure disorder. A karyotype performed at 4 1/2 months of age, by a laboratory elsewhere, reportedly showed a deletion of chromosome 4(p12). When we saw him, he had macrocephaly, hypotonia, psychomotor retardation, multiple minor congenital anomalies, and EEG abnormalities. Repeat chromosomes performed by our laboratory revealed that his karyotype was 46,XY,dir ins(2;4)(p24;p15.3p13). Fluorescence in situ hybridization (FISH) analysis, using chromosomes 2 and 4 painting probes confirmed that material from 4p has been translocated to 2p. Also, FISH analysis using the Wolf-Hirschhorn critical region probe revealed that both loci are intact. Parental chromosomes were normal. This complex rearrangement, though it appears balanced, probably might have resulted in either a structural loss of genetic material or functional loss of a gene action. Thus, his phenotype could be explained by this de novo insertion of chromosome 4 material into chromosome 2. There is no reported case of this specific chromosome rearrangement.

Spontaneous corneal rupture in Noonan syndrome. A case report.

PURPOSE/METHODS: A variety of ocular and periocular manifestations have been described in Noonan syndrome. Collagen abnormalities have been described; however, to our knowledge spontaneous corneal rupture has not been reported. A forty-three-year-old female who presented with spontaneous corneal rupture was later diagnosed as having Noonan syndrome. RESULTS/CONCLUSIONS: Collagen abnormalities have been described with Noonan syndrome and this is likely the cause of corneal rupture in this patient.

17q inversion involving the neurofibromatosis type one locus in a family with neurofibromatosis type one.

We report a family with a paracentric inversion of the long arm of chromosome 17 [inv(17)(q11.2q25.1)] and neurofibromatosis type one (NF1). The family was ascertained because of NF1 and multiple miscarriages. Fluorescence in situ hybridization using cosmid probes from opposite ends of the NF1 gene confirmed that the inversion disrupts the gene. Using field inversion gel electrophoresis we have found that the inversion separates cDNA probes FB5D and AE25, which are normally adjacent to one another in the NF1 gene. This is the third published report of a gross chromosomal rearrangement responsible for NF1. The features in this family are typical for NF1, and are not unusually severe.

Interstitial duplication of proximal 22q: phenotypic overlap with cat eye syndrome.

We describe a child with downslanting palpebral fissures, preauricular malfunctions, congenital heart defect (total anomalous pulmonary venous return), unilateral absence of a kidney, and developmental delay with an apparent interstitial duplication of proximal 22q. Fluorescent in situ hybridization (FISH) analysis showed duplication of the IGLC locus, and C-banding of the duplicated region was negative. The duplication appears to involve 22q11.2-q12. Although the child has neither colobomas nor microphthalmia, he shows phenotypic overlap with the cat eye syndrome, which is caused by a supernumerary bisatellited chromosome arising from inverted duplication of the short arm and proximal long arm of chromosome 22. Further molecular studies of this patient should help to define the regions responsible for the manifestations of cat eye syndrome.

Use of 86Rb and 22Na in assaying active and cotransport activities in human erythrocytes in a biracial population.

A defect in Na+-K+ transport across the red cell membrane has been shown to be associated with essential hypertension. A sensitive assay system to measure active, co- and countertransport systems in erythrocytes from normotensive adults was developed. Active, co- and countertransport systems in the erythrocytes were assayed by measuring the influx of radioactive 22Na+ and 86Rb+. In the biracial (black-white) population group studied, analysis of variance of the active transport showed a significant race effect (p = 0.003). Cotransport activity showed age by race interaction (p = 0.001) and age by sex (p = 0.02). Cotransport activity was significantly higher in whites than blacks (p = 0.0001). Countertransport activity did not vary either by sex or race. Of the Spearman correlation coefficients for transport activities and blood pressure, white males showed a strong positive correlation with countertransport, whereas in black males, blood pressures showed a strong interaction with active transport. Among the transport activities, active transport showed significant interaction with countertransport activity in black males, whereas cotransport activity in whites showed a strong interaction with countertransport. The results suggest a subtle difference in Na+-K+ transport systems between blacks and whites, and these variations may be related to differences for susceptibility to essential hypertension.

A major gene model for the familial aggregation of plasma IgA concentration.

Plasma IgA concentration was determined on 94 individuals of an eastern Kentucky family (IGANI) with some members having clinical and biopsy-proven IgA nephropathy, and on 197 individuals of a large Louisiana family (HGAR29) with no clinical history of IgA nephropathy but on whom 30 polymorphic markers had previously been typed. Pedigree segregation analysis was used to fit a major gene model, and a moderately large lod score for linkage to the ABO locus (1.50 at 0% recombination) suggested the existence of a recessive allele for high plasma IgA concentration. This allele is only slightly more prevalent in pedigree IGANI than in pedigree HGAR29, indicating that it is a minor, rather than a major, etiologic factor in IgA nephropathy.

Segregation and linkage analyses of dopamine-beta-hydroxylase activity in a six-generation pedigree.

Serum dopamine-beta-hydroxylase (DBH) levels and 30 polymorphic markers were determined on 178 individuals of the HGAR 29 family, ascertained through six probands who had clinical and electrocardiographic evidence of myocardial infarction. Individuals in this pedigree with a history of heart attack had significantly lower levels of DBH, but this difference was partly confounded with age differences. Pedigree segregation analysis showed evidence of a codominant gene for DBH segregating in the family. Linkage analysis between the putative DBH locus and 30 polymorphic marker loci, assuming a codominant model, yielded a largest lod score of 0.53, with ABO at 20% recombination. Adding this to the lod scores obtained by Elston et al [1979] and Goldin et al [1982], we obtain combined lod scores of 2.49 and 2.50 at 0.0 and 10% recombination respectively.