Modeling HLA associations with EBV-positive and -negative Hodgkin lymphoma suggests distinct mechanisms in disease pathogenesis.

HLA genotyping and genome wide association studies provide strong evidence for associations between Human Leukocyte Antigen (HLA) alleles and classical Hodgkin lymphoma (cHL). Analysis of these associations is complicated by the extensive linkage disequilibrium within the major histocompatibility region and recent data suggesting that associations with EBV-positive and EBV-negative cHL are largely distinct. To distinguish independent and therefore potentially causal associations from associations confounded by linkage disequilibrium, we applied a variable selection regression modeling procedure to directly typed HLA class I and II genes and selected SNPs from EBV-stratified patient subgroups.

Genome-wide association study of classical Hodgkin lymphoma and Epstein-Barr virus status-defined subgroups.

Background: Accumulating evidence suggests that risk factors for classical Hodgkin lymphoma (cHL) differ by tumor Epstein-Barr virus (EBV) status. This potential etiological heterogeneity is not recognized in current disease classification.

Methods: We conducted a genome-wide association study of 1200 cHL patients and 6417 control subjects, with validation in an independent replication series, to identify common genetic variants associated with total cHL and subtypes defined by tumor EBV status.

The retrovirus XMRV is not directly involved in the pathogenesis of common types of lymphoid malignancy.

Background: A novel retrovirus, xenotropic murine leukemia virus-related virus (XMRV), has been detected in prostate cancer samples and in peripheral blood mononuclear cells (PBMC) from patients with chronic fatigue syndrome. In addition, the virus has been identified in PBMCs from healthy controls. These data suggest that XMRV is circulating in the human population.

A genome-wide association study of Hodgkin's lymphoma identifies new susceptibility loci at 2p16.1 (REL), 8q24.21 and 10p14 (GATA3).

To identify susceptibility loci for classical Hodgkin's lymphoma (cHL), we conducted a genome-wide association study of 589 individuals with cHL (cases) and 5,199 controls with validation in four independent samples totaling 2,057 cases and 3,416 controls. We identified three new susceptibility loci at 2p16.1 (rs1432295, REL, odds ratio (OR) = 1.

SLC6A4 expression and anti-proliferative responses to serotonin transporter ligands chlomipramine and fluoxetine in primary B-cell malignancies.

B-cell lines of diverse neoplastic origin express the serotonin transporter (SERT/SLC6A4) and growth arrest in response to SERT-ligands, including the antidepressants chlomipramine and fluoxetine. Here we detail SLC6A4 transcript (Q-PCR) and protein (FACS) expression in primary cells from patients with: chronic lymphocytic leukaemia; mantle cell lymphoma; follicular lymphoma; Burkitt's lymphoma; and diffuse large B-cell lymphoma. The ability of the SERT-binding antidepressants to impact the growth of these cells when sustained on CD154-transfected fibroblasts was also determined.

HLA-A alleles and infectious mononucleosis suggest a critical role for cytotoxic T-cell response in EBV-related Hodgkin lymphoma.

A proportion of classical Hodgkin lymphoma (HL) is believed to be causally related to infection with the ubiquitous lymphotropic EBV. The determining factors for development of EBV-related HL remain poorly understood, but likely involve immunological control of the viral infection. Accordingly, markers of the HLA class I region have been associated with risk of EBV-related HL.

Mutations of NFKBIA, encoding IkappaB alpha, are a recurrent finding in classical Hodgkin lymphoma but are not a unifying feature of non-EBV-associated cases.

A consistent feature of the Hodgkin and Reed-Sternberg (HRS) cells in classical Hodgkin lymphoma (cHL) is the constitutive activation of NF-kappaB transcription factors. In Epstein-Barr virus (EBV)-associated cases of cHL, expression of viral antigens most probably leads to NF-kappaB activation but for non-EBV-associated cases, the mechanism is not clear. Previous small studies have demonstrated deleterious mutations of NFKBIA, the gene encoding IkappaB alpha, in HRS cells.

Adolescent spinal muscular atrophy with calf hypertrophy and a deletion in the SMN gene.

Spinal muscular atrophy (SMA) is generally associated with proximal weakness and muscle wasting. An X-linked variant with calf hypertrophy has been reported. We describe a young man with SMA type 4 with prominent calf hypertrophy in whom DNA analysis showed a homozygous deletion of exons 7 and 8 in the telomeric copy of the survival motor neuron gene.

Viruses and Hodgkin lymphoma: no evidence of polyomavirus genomes in tumor biopsies.

The epidemiology of young adult Hodgkin lymphoma (HL) suggests that delayed exposure to a common childhood pathogen may be involved in disease pathogenesis. The Epstein-Barr virus (EBV) is associated with a proportion of cases but cases of young adult HL in westernized countries are less frequently EBV-associated than cases in other age groups and geographical locales. This study investigated the possibility that polyomaviruses might be involved in the etiology of HL by analysing a series of 35 cases of classical HL using both specific and degenerate PCR assays for polyomavirus genomes.

SEPN1: associated with congenital fiber-type disproportion and insulin resistance.

Objective: Our first objective was to determine whether SEPN1 gene mutations are a cause of congenital fiber-type disproportion (CFTD), a rare form of congenital myopathy in which relative hypotrophy of type 1 (slow twitch) muscle fibers is the principal abnormality on histology. Second, we investigated an association between SEPN1-related myopathy and insulin resistance.

Methods: We sequenced SEPN1 in five unrelated CFTD patients with scoliosis and respiratory muscle weakness and screened an additional 22 CFTD patients for abnormalities in SEPN1 by Western blotting and restriction digest for the 943G-->A mutation.

Subacute inflammatory demyelinating polyneuropathy in children.

Reported are five children with subacute demyelinating polyneuropathy. All patients had a monophasic disease, progressing over 4 to 8 weeks and characterized by predominantly motor features, areflexia, minimal or no cranial nerve abnormalities, no autonomic or respiratory involvement, elevated CSF protein, electrophysiologic evidence of demyelination, and good response to corticosteroids. A benign course with full recovery was the rule.

Phenotype and frequency of Epstein-Barr virus-infected cells in pretreatment blood samples from patients with Hodgkin lymphoma.

An accumulating body of data suggests that the Epstein-Barr virus (EBV), a lymphotropic herpesvirus, is involved in the pathogenesis of a proportion of cases of Hodgkin lymphoma (HL). In this study, we showed that the frequency of circulating EBV-infected cells was significantly higher (P < 0.001) in pretreatment blood samples from EBV-associated cases when compared with non-EBV-associated cases.

Effect of IL-6 promoter polymorphism on incidence and outcome in Hodgkin's lymphoma.

A single nucleotide polymorphism (SNP) is present at position -174 of the human interleukin-6 gene. The risk of developing Hodgkin's lymphoma (HL) in young adults decreases with an increasing number of C alleles at this position. We analysed the effect of this SNP on incidence and outcome in HL.

Neuropsychological outcome after acute disseminated encephalomyelitis: impact of age at illness onset.

Recovery from acute disseminated encephalomyelitis in childhood appears relatively uneventful, at least when looking at functional recovery parameters such as neurologic outcome. However, neuropsychology literature suggests that relatively transient illnesses affecting the central nervous system are associated with cognitive and social sequelae, particularly when the illness occurs during the preschool years. This study investigated the impact of timing of acute disseminated encephalomyelitis on intellectual, educational, and social functioning in children.

Classical Hodgkin lymphoma is associated with frequent gains of 17q.

The etiology of Hodgkin lymphoma (HL) is poorly understood, and studies of the genetics of this disease have been hampered by the scarcity of the Hodgkin and Reed-Sternberg (HRS) cells within tumors. To determine whether recurrent genomic imbalances are a feature of HL, CD30-positive HRS cells were laser-microdissected from 20 classical Hodgkin lymphomas (cHLs) and four HL-derived cells lines and subjected to analyses by comparative genomic hybridization. In primary tumors, the most frequently involved chromosomal gains were 17q (70%), 2p (40%), 12q (40%), 17p (40%), 22q (35%), 9p (30%), 14q (30%), and 16p (30%), with minimal overlapping regions at 17q21, 2p23-13, 12q24, 17p13, 22q13, 9p24-23, 14q32, 16p13.

Clinical course correlates poorly with muscle pathology in nemaline myopathy.

Objective: To report pathologic findings in 124 Australian and North American cases of primary nemaline myopathy.

Methods: Results of 164 muscle biopsies from 124 Australian and North American patients with primary nemaline myopathy were reviewed, including biopsies from 19 patients with nemaline myopathy due to alpha-actin (ACTA1) mutations and three with mutations in alpha-tropomyosin(SLOW) (TPM3). For each biopsy rod number per fiber, percentage of fibers with rods, fiber-type distribution of rods, and presence or absence of intranuclear rods were documented.

Hodgkin lymphoma and Epstein-Barr virus (EBV): no evidence to support hit-and-run mechanism in cases classified as non-EBV-associated.

The Epstein-Barr virus (EBV) is associated with a proportion of Hodgkin lymphoma (HL) cases, and this association is believed to be causal. The aetiology of cases lacking EBV in the tumour cells (EBV HRS-ve), which make up the majority of cases in western countries, is obscure. It has been suggested that EBV may also cause these tumours by using a hit-and-run mechanism.

Childhood chronic inflammatory demyelinating polyneuropathy with central nervous system demyelination resembling multiple sclerosis.

Central nervous system demyelination has been described in adults but not in children with chronic inflammatory demyelinating polyneuropathy. We describe a patient with clinical and electrophysiological features consistent with chronic inflammatory demyelinating polyneuropathy who presented at age 5 with an intramedullary spinal cord tumor-like lesion and at age 8, represented with cerebral and spinal demyelinating lesions. Her clinical course and magnetic resonance imaging features were atypical for multiphasic disseminated encephalomyelitis and indistinguishable from multiple sclerosis.

Viruses and Hodgkin disease: no evidence of novel herpesviruses in non-EBV-associated lesions.

The Epstein-Barr virus (EBV) is associated with a proportion of cases of Hodgkin disease (HD) and this association is believed to be causal. Epidemiological studies suggest that an infectious agent is involved in the aetiology of young adult HD, however, cases in this age group are less likely to have EBV-associated disease than cases diagnosed in early childhood or older adult years. Molecular studies have failed to find a consistent association between HD and other candidate viruses, and the aetiology of non-EBV-associated cases remains obscure.

Hemiconvulsion-hemiplegia-epilepsy syndrome: characteristic early magnetic resonance imaging findings.

We report three patients with hemiconvulsion-hemiplegia-epilepsy syndrome who presented acutely and were shown to have striking neuroimaging findings suggestive of diffuse cytotoxic edema confined to one hemisphere, including extensive diffusion-weighted imaging abnormalities in two cases. Two patients subsequently developed progressive and extensive atrophy of the involved hemisphere. These findings are consistent with earlier descriptions of the classic neuroradiologic features of this syndrome and are helpful in the differential diagnosis of acute infantile hemiplegia.

Nemaline myopathy: a clinical study of 143 cases.

We report 143 Australian and North American cases of primary nemaline myopathy. As classified by the European Neuromuscular Centre guidelines, 23 patients had severe congenital, 29 intermediate congenital, 66 typical congenital, 19 childhood-onset, and 6 adult-onset nemaline myopathy. Inheritance was autosomal recessive in 29 patients, autosomal dominant in 41, sporadic in 72, and indeterminate in 1.

Clinical and neuroradiologic features of acute disseminated encephalomyelitis in children.

Objective: To identify the clinical and neuroradiologic features of acute disseminated encephalomyelitis (ADEM) in childhood.

Methods: A retrospective review was conducted of the medical records and MRI of children who presented to the Royal Children's Hospital in Melbourne with ADEM between January 1993 and December 1998.

Results: Of the 31 patients included in this study, 22 (71%) experienced a prodromal illness.