A Sri Lankan child with 49,XXXXY syndrome

Pentasomy 49,XXXXY is a rare sex chromosome disorder usually presenting with ambigous genitalia, facial dysmorphism, mental retardation and a combination of cardiac, skeletal and other malformations. The incidence of the condition is estimated to be 1 in 85,000 male births. Previously, this condition was identified as a Klinefelter variant. The condition is suspected in a patient, by a combination of characteristic clinical findings, and the diagnosis is confirmed by chromosome culture and karyotyping. In the case we report here, the main presentation of ambiguous genitalia led to a suspicion of a sex chromosome aneuploidy which was subsequently confirmed by chromosomal analysis.     

Skeletal abnormalities of the upper limbs — Neonatal diagnosis of 49,XXXXY syndrome

A case of neonatal diagnosis of 49,XXXXY syndrome is presented. Clinical identification was prompted by a bilateral thickening of the radioulnar joints and X-ray imaging disclosing almost complete radioulnar synostosis. Conventional karyotyping was initiated and revealed a karyotype of 49,XXXXY. Previously reported neonatal symptoms such as low birth weight, muscular hypotonia, or genital malformations were absent in this case. Microsatellite analysis showed two different X chromosomes each present in two copies, supporting that the four X chromosomes had arisen from a nondisjunction in maternal meiosis I followed by a second nondisjunction involving both X chromosomes in meiosis II. Multidisciplinary follow-up was organised to ensure timely recognition of associated complications. Early awareness of the diagnosis may offer a potential benefit regarding outcome.     

Type 2 diabetes mellitus: An unusual association with Down's syndrome

Down''s syndrome (DS) is known to be associated with autoimmune disease including type 1 diabetes. To the best of our knowledge, there are no reports of DS with type 2 diabetes mellitus in the literature. We hereby report two cases of DS with type 2 diabetes.     

Gestational diabetes mellitus: a syndrome with phenotypic and genotypic heterogeneity

One hundred ninety-nine gravida with gestational diabetes mellitus (GDM) defined as "carbohydrate intolerance of varying severity with onset or first recognition during pregnancy" have been stratified into subgroups on the basis of fasting plasma glucose and evaluated for further phenotypic and genotypic heterogeneity. A significantly greater proportion of the women in all our groups were older and heavier than in a "control" population of 148 consecutive gravida with documented normal oral glucose tolerance. After correction for age and weight by covariate analysis, absolute insulinopenia in response to oral glucose could be demonstrated in all GDM groups, although exceptions were present in each. The incidence of diabetes in the mothers of our patients with GDM was 8-fold greater than in controls; the incidence in fathers did not deviate from control patterns. HLA-DR3 and DR4 antigens were more frequently present in GDM and the increase was statistically significant in blacks. At the time of diagnosis, cytoplasmic islet cell antibodies (ICA) were significantly more common in GDM associated with elevated fasting plasma glucose than in controls; the frequency of ICA was 18.4% (7/38) in women with fasting plasma glucose greater than or equal to 130 mg/dl. Our findings indicate that GDM entails genotypic as well as phenotypic diversity and may include patients with slowly-evolving Type I diabetes mellitus, as well as patients with Type II diabetes mellitus, and women with asymptomatic diabetes which antedated the pregnancy (i.e. pregestational diabetes mellitus). Appreciation of this heterogeneity should be incorporated into any evaluation of intervention strategies for women with GDM or into prognoses concerning their postpartum metabolic status.     

Neuropathy in a patient with McArdle's syndrome and diabetes mellitus.

A juvenile-type diabetic patient of five years standing presented with a mononeuritis and gave a history of painful muscle swelling induced by exertion. Failure of the blood lactate to rise during ischaemic exercise and a normal blood glucose rise following intravenous glucagon confirmed the clinical diagnosis of muscle glycogenosis. The association of diabetes and McArdle's Syndrome has not previously been documented. An ulnar nerve palsy, which persisted for many months, followed the ischaemic exercise test possibly due to compression by muscular swelling, but may have been exacerbated by the co-existing diabetes.     

XXXXY syndrome in a phenotypic male infant with associated cardiac abnormalities

Summary A boy with 49,XXXXY karyotype is described with only mild mental retardation at 18 months. Physical abnormalities included patent ductus arteriosus, undescended testes, small penis, bilateral epicanthal folds, and incurved 5th digits with small middle phalanges. Literature review showed 7 previous cases of XXXXY patients with congenital heart disease. 23% of buccal cells showed 1 sex chromatin body; 26% showed 2 and 11% 3. Autoradiography demonstrated 3 heavily labelled X chromosomes. The heteropyknotic behavior of X Chromosomes in excess of one may provide some measure of protection against excessive numbers of X chromosomes, bence the relatively normal development of some XXXXY patients.This study was supported in part by research grant AM-02504 from the National Institute of Arthritis and Metabolic Diseases U.S. Public Health Service.     

A 7-year-old boy with 49,XYYYY syndrome

The growth and development of a child with a 49,XYYYY karyotype is reported. The main features are a large stature, speech delay, and sensorimotor dysfunction.     

The 48,XXXX/49,XXXXY/49,XXXX,i(Yq) mosaicism in a 3-year-old boy from a twin pregnancy

Summary A 3-year-old boy from twin pregnancy with the features of marked dystrophia from birth, deficient growth, considerable retardation of physical and mental development, numerous somatic defects, suspected congenital heart disease, and hypoplastic external genitalia, is reported. The 48,XXXX/49,XXXXY/49,XXXX,i(Yq) karyotype was diagnosed. The boy's brother, normally developed, had a 46,XY karyotype. It was found on the basis of serologic findings that the brothers were dizygotic twins.     

Determination of the origin of nondisjunction in a 49,XXXXY male using hypervariable dinucleotide repeat sequences

Summary We present a patient with a 49,XXXXY chromosome constitution in whom the origin of the extra X chromosomes was determined by analysis of five polymorphic CA (or GT) dinucleotide repeat sequences. This class of DNA marker has recently been demonstrated to be hypervariable with heterozygosity values up to 80%. By polymerase chain reaction (PCR) analysis of the dinucleotide repeat length polymorphisms, we have shown that all four X chromosomes were of maternal origin.     

Cytokine profile, metabolic syndrome and cardiovascular disease risk in women with late-onset gestational diabetes mellitus

Inflammation is an important component of the metabolic syndrome (MetS) which could be the link between the metabolic and the cardiovascular consequences of this condition. Gestational diabetes mellitus (GDM) has been recognized as a significant risk factor for MetS and an inflammation component has been described in this disease. The aim of the study was to evaluate the relationships between cytokine concentrations, components of MetS and cardiovascular risk markers in women with late-onset GDM. Women (n=63) with late-onset GDM and 63 controls were enrolled. Clinical variables, and obstetrics and perinatal outcomes were recorded. Relationships between cytokines (TNF-α, leptin, IL6, adiponectin) and endothelial injury markers (VCAM, ICAM and selectine) were analyzed. Control vs. patient data indicated: pre-gestational body mass index (BMI) 23.46±3.73 vs. 26.97±5.07kg/m(2) (p=0.001); TNF-α 2.2±0.8 vs. 3.1±1.5pg/mL (p=0.002); leptin 18714.78±8859.08 vs. 27365.79±16209.67pg/mL (p=0.001); adiponectin 162.42±34.19 vs. 141.54±41.33ng/mL (p=0.04). Multivariate analyses showed that adiponectin had a protective effect (OR=0.9; p=0.02) and BMI carried a significant risk (OR=8.4; p=0.01) for GDM. No differences were found in endothelial injury markers. In conclusion, the cytokine profile in women with late-onset GDM is characterized by high concentrations of TNF-α and leptin and low adiponectin. This profile is related, in large extent, to an increased pregravid BMI which, potentially, may be linked to the future development of both metabolic and cardiovascular disease.     

Magnesium metabolism in type 2 diabetes mellitus, metabolic syndrome and insulin resistance

Type 2 diabetes is characterized by cellular and extracellular Mg depletion. Epidemiologic studies showed a high prevalence of hypomagnesaemia and lower intracellular Mg concentrations in diabetic subjects. Insulin and glucose are important regulators of Mg metabolism. Intracellular Mg plays a key role in regulating insulin action, insulin-mediated-glucose uptake and vascular tone. Reduced intracellular Mg concentrations result in a defective tyrosine-kinase activity, post-receptorial impairment in insulin action, and worsening of insulin resistance in diabetic patients. Mg deficit has been proposed as a possible underlying common mechanism of the "insulin resistance" of different metabolic conditions. Low dietary Mg intake is also related to the development of type 2 diabetes. Benefits of Mg supplementation on metabolic profile in diabetic subjects have been found in most, but not all clinical studies, and larger prospective studies are needed to support the potential role of dietary Mg supplementation as a possible public health strategy in diabetes risk.     

A maternal hypomethylation syndrome presenting as transient neonatal diabetes mellitus

The expression of imprinted genes is mediated by allele-specific epigenetic modification of genomic DNA and chromatin, including parent of origin-specific DNA methylation. Dysregulation of these genes causes a range of disorders affecting pre- and post-natal growth and neurological function. We investigated a cohort of 12 patients with transient neonatal diabetes whose disease was caused by loss of maternal methylation at the TNDM locus. We found that six of these patients showed a spectrum of methylation loss, mosaic with respect to the extent of the methylation loss, the tissues affected and the genetic loci involved. Five maternally methylated loci were affected, while one maternally methylated and two paternally methylated loci were spared. These patients had higher birth weight and were more phenotypically diverse than other TNDM patients with different aetiologies, presumably reflecting the influence of dysregulation of multiple imprinted genes. We propose the existence of a maternal hypomethylation syndrome, and therefore suggest that any patient with methylation loss at one maternally-methylated locus may also manifest methylation loss at other loci, potentially complicating or even confounding the clinical presentation.Electronic Supplementary Material Supplementary material is available to authorised users in the online version of this article at .