Constitutional UPD for chromosome 11p15 in individuals with isolated hemihyperplasia is associated with high tumor risk and occurs following assisted reproductive technologies

Isolated hemihyperplasia (IH) refers to a distinct diagnosis involving asymmetric overgrowth of single or multiple organs or regions of the body and can result from various genomic changes including molecular alterations of 11p15; these are paternal uniparental disomy (UPD), and alterations of methylation at two imprinting centers at 11p15: IC1 (H19) and IC2 (KCNQ1OT1). As little information is available on the molecular basis of tumor development in IH, or on the frequency of tumors in children with different molecular subtypes of IH, molecular testing was undertaken on 51 patients with IH and revealed: 8 (16%) with UPD, 3 (6%) with hypomethylation at KCNQ1OT1, and 0 with hypermethylation at H19. Of the 8 patients with UPD, 4 had tumors (3 hepatoblastomas, 1 Wilms tumor); 0/3 patients with hypomethylation at KCNQ1OT1 had a tumor; of the remaining 40 with no molecular alterations, 6 had tumors (3 Wilms tumors, 2 neuroblastomas, 1 adrenocortical adenoma). The 50% tumor frequency in patients with IH and UPD was statistically significantly higher than the 15% tumor frequency in those with IH and no molecular alteration detected (Fisher's exact test P = 0.047, OR 5.67). This is the first demonstration that UPD at 11p15 in patients with IH confers a higher tumor risk than in patients with IH without this molecular change. Of note, two of the eight patients with UPD and IH were conceived using assisted reproductive technologies (ART), thus raising the question whether ART might impact the rate of somatic recombination during embryonic development.     

Autoantibodies against the platelet glycoprotein IIb/IIIa complex in patients with chronic ITP

Chronic idiopathic thrombocytopenic purpura (ITP) is caused by an antibody reactive with platelet-associated antigens. The present studies provide direct evidence that some patients with chronic ITP have autoantibodies against the platelet glycoprotein (GP) IIb/IIIa complex. Microtiter wells, coated with a monoclonal antibody (2G12) specific for GPIIb/GPIIIa were reacted with GPIIb/GPIIIa contained in a platelet extract. Control wells containing the same antibody were reacted with a cell extract containing no GPIIb/GPIIIa. After washing, the wells were reacted with patient or control plasma, and IgG binding was detected using 125I-Fab2-anti-human IgG. Assay values were expressed as binding ratios (cpm GPIIb/GPIIIa wells/cpm control wells). Plasma from 5 of 56 patients with chronic ITP had ratios (1.36-3.14) greater than 3 standard deviations above the mean (+/- SD) of control plasmas--0.93 +/- 0.12. Elevated values were also noted in two patients with anti-P1A1 antibody (ratios greater than 30) and in one patient with Hodgkin's disease and an ITP-like syndrome (ratio 1.53). Normal values were noted in 34 patients with a variety of immune and nonimmune diseases. Plasma from two of the positive ITP patients was reacted with 125I-surface-labeled platelets and, after solubilization, the IgG and bound antigen were precipitated with Staph-A. Autoradiographs from SDS- PAGE electrophoresis of the Staph-A-bound proteins shows two radioactive bands consistent in size with GPIIb and GPIIIa.     

The first report of a patient with interrupted inferior vena cava,multiple post-renal veins and azygos-hemiazygos continuation

The first case of a patient with interrupted inferior vena cava, four post-renal veins and an azygoshemiazygos continuation is presented. The complicated anomalies were omphalocele and atrial septal defect. Cine-magnetic resonance imaging and cardiac catheterization showed an anomalous retroaortic left innominate vein, azygos-hemiazygos continuation in the prerenal portion, arch formed renal vein in the renal portion and four embryonic vessels in the post-renal portion. Combination of these anomalies in the major venous system suggested that the inferior vena cava had failed to form and that the bilateral embryonic venous system, postcardinal and supracardinal veins persisted to be the systemic venous channels.     

Mycobacterial infection in an inner city children's hospital

Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.     

Congenital scoliosis and vertebral malformations: characterization of segmental defects for genetic analysis

The developmental and genetic etiology of most congenital vertebral malformation disorders remains unknown. The objective of this study was to evaluate and classify congenital vertebral defect cases into groupings based on developmental etiology for clinical genetic studies. This classification is intended to be distinct from but complementary to traditional groupings based on spinal curvature or progression. In the first step of this analysis, the authors identified 84 cases of vertebral segmentation disorders by radiologic screening and prospectively recruited 39 of these patients into a clinical genetic study. Next, the authors quantified the extent of contiguous defects and organized cases by craniocaudal localization. Finally, the authors used available clinical association data to identify syndromic and nonsyndromic subcategories, and identified a high rate of orthopaedic and neurologic associations in nonsyndromic patients. This type of analysis has identified subgroups of patients with multiple, contiguous segmental defects and orthopaedic associations that are particularly suitable for further genetic analysis.