The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry

Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus is determined by a combination of environmental and genetic factors, which include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2 cannot explain the clustering of type 1 diabetes in families, and a role for other genes is inferred. In the present report we describe linkage and association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong candidate gene for T cell- mediated autoimmune disease because it encodes a T cell receptor that mediates T cell apoptosis and is a vital negative regulator of T cell activation. In addition, we provide supporting evidence that CTLA-4 is associated with susceptibility to Graves' disease, another organ- specific autoimmune disease.      

Neuroimaging findings in infantile GM1 gangliosidosis

GM1 gangliosidosis is an autosomal recessive glycosphingolipid storage disease caused by defects in the enzyme beta-galactosidase. Three clinical forms (infantile-, juvenile-, and adult-onset) of the disease are recognized. Patients with infantile GM1 gangliosidosis present at birth or shortly thereafter with somatic and bony changes, followed by severe neurological deterioration ultimately leading to death within the first 2 years of life. We present the brain CT, MRI and MR spectroscopy (MRS) findings in a 17-month-old Turkish girl with infantile GM1 gangliosidosis. Neuroimaging findings in patients with infantile GM1 gangliosidosis have been reported only in a few cases. In this study, MRS of the thalamus was performed to study the metabolic changes in GM1 gangliosidosis. We showed a a decreased NAA/Cr ration and an increased Cho/Cr ratio. To our knowledge, this is the first report of magnetic resonance spectroscopy findings in type-1 GM1 gangliosidosis.     

Neurocognitive Functions in Pediatric Renal Transplant Patients

Neurocognitive dysfunction is one of the major complications of chronic renal failure (CRF). Uremic state during CRF encompasses a wide spectrum of neurobehavioral and neurological disturbances. Recent studies showed that the pathophysiology of neurocognitive dysfunction in CRF is related to plasma levels of uremic solutes. Successful renal transplantation improves renal, metabolic, and endocrine functions and the quality of life. The aim of our study was to determine the state of neurocognitive function in pediatric renal transplant recipients. We prospectively performed a neurological examination and neuropsychological test battery (Bender-Gestalt Test, Cancellation Test, and Visual and Auditory Number Assay Test) in 20 pediatric renal transplant recipients between 6 and 16 years of age. Twenty healthy children and 20 children with CRF were included in the study as the control groups. Mean age of the renal transplant recipients was 13.50 ± 3.40 years old. Mean evaluation time after transplantation was 2.0 ± 0.5 years. Bender-Gestalt Test result was abnormal in 40% of patients. The results of the Cancellation Test and the Visual and Auditory Number Assay Test showed significant decline in pediatric renal transplant patients when compared with the control. We found that neurocognitive dysfunction was frequent in pediatric renal transplantation patients. Awareness of this potential problem may be helpful for early recognition and treatment. Our findings suggest that periodic neurocognitive assessments may be indicated in transplant recipients.     

Clinical features of isolated left ventricular noncompaction in children

BACKGROUND: Ventricular noncompaction is a rare unclassified cardiomyopathy due to intrauterin arrest of compaction of the loose interwoven meshwork with limited data regarding diagnosis and outcome in children. METHODS: In this study we describe clinical features of isolated left ventricular noncompaction (IVNC) in children and compare our findings with those previously reported. A diagnosis of ventricular noncompaction was made according to the characteristic echocardiographic appearance of two-layered myocardial wall consisting of a thin compacted epicardial and a thick noncompacted endocardial layer with numerous, prominent trabeculations and deep intertrabecular recesses communicating with left ventricular cavity. RESULTS: Nine children, eight male and one female, with ages ranging from 10 days to 12 years and follow-up as long as 5 years were included into the study. The primary diagnosis of IVNC had been missed in four of the patients. Clinical manifestations were heart failure in five patients, cardiac murmur in two, dizziness in one, and palpitation in one patient. All patients, except two asymptomatic ones, had electrocardiographic abnormalities. Four patients required hospital admission for decompansated heart failure. Two patients died during follow-up while waiting for heart transplantation. Familial occurrence, ventricular tachycardia and thromboembolic events were not observed in any of the patients. CONCLUSIONS: Although IVNC is present at birth, it may become clinically overt at any time from infancy through adolescence. Physicians and echocardiographers should be familiar with the diagnostic pattern of ventricular noncompaction in order to prevent any delay in diagnosis. Since associated morbidity and mortality rates are high, these patients require regular follow-up.     

Mitral and aortic insufficiency in polyarticular juvenile rheumatoid arthritis

Summary Valvar heart disease is a rare complication of juvenile rheumatoid arthritis (JRA), the aortic valve being most commonly affected. Reported cases with symptomatic mitral involvement are rare. We describe a 13-year-old boy with seronegative, polyarticular onset of JRA in whom mitral and aortic valve insufficiency was diagnosed by clinical and laboratory investigations. Two-dimensional and continuous-wave Doppler echocardiography confirmed mild pericardial effusion with moderate mitral and mild aortic insufficiency. Cardiac assessment and echocardiogrphic follow-up are recommended in all patients with JRA.