Natural history of multiple sclerosis with childhood onset.

BACKGROUND: The course and prognosis of childhood-onset multiple sclerosis have not been well described. METHODS: We used data from 13 adult neurology departments affiliated with the European Database for Multiple Sclerosis (EDMUS) network to identify a cohort of 394 patients who had multiple sclerosis with an onset at 16 years of age or younger and a comparison group of 1775 patients who had multiple sclerosis with an onset after 16 years of age. We determined the initial clinical features, the dates of disease onset, and the occurrence of outcomes, including relapse, conversion to secondary progression, and irreversible disability as measured by scores of 4 (limited walking ability but ability to walk more than 500 m without aid or rest), 6 (ability to walk with unilateral support no more than 100 m without rest), and 7 (ability to walk no more than 10 m without rest while using a wall or furniture for support) on the Kurtzke Disability Status Scale (range, 0 to 10; higher scores indicate more severe disability). RESULTS: For patients with childhood-onset multiple sclerosis, the estimated median time from onset to secondary progression was 28 years, and the median age at conversion to secondary progression was 41 years. The median times from onset to disability scores of 4, 6, and 7 were 20.0, 28.9, and 37.0 years, respectively, and the corresponding median ages were 34.6, 42.2, and 50.5 years. In comparison with patients with adult-onset disease, those with childhood-onset disease were more likely to be female than male (female:male ratio, 2.8 vs. 1.8), were more likely to have an exacerbating-remitting initial course (98% vs. 84%), took approximately 10 years longer to reach secondary progression and irreversible disability, and reached these landmarks at an age approximately 10 years younger (P<0.001 for all comparisons). CONCLUSIONS: Patients with childhood-onset multiple sclerosis take longer to reach states of irreversible disability but do so at a younger age than patients with adult-onset multiple sclerosis.

COL4A1 mutations and hereditary angiopathy, nephropathy, aneurysms, and muscle cramps.

BACKGROUND: COL4A3, COL4A4, and COL4A5 are the only collagen genes that have been implicated in inherited nephropathies in humans. However, the causative genes for a number of hereditary multicystic kidney diseases, myopathies with cramps, and heritable intracranial aneurysms remain unknown. METHODS: We characterized the renal and extrarenal phenotypes of subjects from three families who had an autosomal dominant hereditary angiopathy with nephropathy, aneurysms, and muscle cramps (HANAC), which we propose is a syndrome. Linkage studies involving microsatellite markers flanking the COL4A1-COL4A2 locus were performed, followed by sequence analysis of COL4A1 complementary DNA extracted from skin-fibroblast specimens from the subjects. RESULTS: We identified three closely located glycine mutations in exons 24 and 25 of the gene COL4A1, which encodes procollagen type IV alpha1. The clinical renal manifestations of the HANAC syndrome in these families include hematuria and bilateral, large cysts. Histologic analysis revealed complex basement-membrane defects in kidney and skin. The systemic angiopathy of the HANAC syndrome appears to affect both small vessels and large arteries. CONCLUSIONS: COL4A1 may be a candidate gene in unexplained familial syndromes with autosomal dominant hematuria, cystic kidney disease, intracranial aneurysms, and muscle cramps.

Autosomal-dominant familial hematuria with retinal arteriolar tortuosity and contractures: a novel syndrome.

BACKGROUND: Autosomal-dominant forms of hematuria have been mostly related to mutations in the COL4A3/COL4A4 genes. Patients with thin basement membrane (BM) disease do not have extrarenal manifestations, while those with Alport syndrome often present with hearing loss, anterior lenticonus, and dot-and-fleck retinopathy. METHODS: We performed a phenotypic study and a candidate gene approach in a four-generation family presenting with autosomal-dominant hematuria associated with extrarenal manifestations. Renal biopsy was analyzed for determination of BM thickness and expression of chains of type IV collagen. Linkage to 18 candidate genes/loci was investigated using polymorphic microsatellite markers. RESULTS: In all affected patients, hematuria without proteinuria was associated with muscular contractures and retinal arterial tortuosities responsible for retinal hemorrhages. Cardiac arrhythmia, Raynaud phenomena, and brain MRI abnormalities were also observed. Despite the presence of red cells in tubule sections, no glomerular abnormalities were found by electron microscopy. Expression of type IV collagen chains and glomerular BM thickness was normal. We searched for a molecular defect affecting either BM or angiogenesis. Linkage analyses of genes encoding BM components (COL4A3/COL4A4, COL6A1, COL6A2, COL6A3, FBLN1), and angiogenic factors or their receptors (VHL, ANPT1, ANPT2, TIE, TEK, NOTCH2, NOTCH3, NOTCH4, DLL4, JAG1, JAG2) and of the facio-sapulo-humeral dystrophy and 3q21 loci failed to show segregation of the disease with those gene loci. CONCLUSION: We have identified a new inherited hematuria syndrome associated with retinal vessel tortuosities and contractures. We recommend performing a fundus examination in patients with familial hematuria and episodes of visual impairment, as well as a urinary analysis in patients with retinal arterial tortuosity or congenital muscular contractures.