Congenital myasthenic syndromes (CMS) are clinically and genetically heterogeneous inherited disorders characterized by impaired neuromuscular transmission. Mutations in the acetylcholinesterase (AChE) collagen-like tail subunit gene (COLQ) cause synaptic basal-lamina associated CMS with end-plate AChE deficiency. Here we present the clinical and molecular genetic findings of 22 COLQ-mutant CMS patients, carrying a total of 20 different COLQ mutations, 11 of them had not previously been reported. Typically, patients with esterase deficiency suffer from a severe, progressive weakness with onset at birth or in early infancy. In addition, patients with a late onset showing a mild course of disease are described. AChE inhibitor therapy, beneficial for other forms of CMS, is of no effect in cases of esterase deficiency. The large cohort of COLQ patients studied here enabled us to define additional clinical presentations associated with COLQ mutations that differ from the 'classical' phenotypes: several patients with disease onset at birth or in early infancy presented an unexpected, mild disease course without significant progression of weakness. Moreover, many patients had clinical features reminiscent of limb-girdle CMS with mutations in the recently discovered DOK7 gene, including sparing of eye movements and a predominantly proximal muscle weakness. There was no long-term objective benefit from esterase inhibitors treatment in COLQ patients. Surprisingly, a short-term beneficial effect was observed in four patients and a Tensilon test was positive in two. Treatment with ephedrine was efficient in all five cases where it was administered. The variability of phenotypes caused by COLQ mutations, the divergence from the previously published classical clinical features and an initial positive response to esterase inhibitors in some patients may obscure AChE deficiency as the molecular cause of the disease and delay the start of appropriate therapy. Moreover, overlap with other CMS subtypes and potentially absence of a repetitive compound muscle action potential should be considered in the diagnosis of COLQ-mutated patients.

OBJECTIVETo investigate whether celiac disease (CD) associated with type 1 diabetes increases the risk of microvascular complications. RESEARCH DESIGN AND METHODSPatients (n = 56,514) aged >10 years with diabetes duration <20 years from 392 centers in Germany and Austria were assigned to one of three categories (n): no CD (50,933), biopsy-confirmed CD (812), or suspected CD (4,769; clinical diagnosis or positive antibodies). The confirmed and suspected groups were combined and analyzed for retinopathy or nephropathy. Cox proportional hazards regression was used to adjust for potential confounders (glycated hemoglobin [HbA 1c ], age at diabetes onset, sex, smoking, dyslipidemia, and hypertension). RESULTSKaplan-Meier analysis revealed that retinopathy and nephropathy occurred earlier in the presence versus absence of CD: retinopathy at age 26.7 years (95% CI 23.7-30.2) in 25% of patients with CD vs. age 33.7 years (33.2-34.4) in 25% without CD and microalbuminuria at age 32.8 years (29.7-42.5) vs. 42.4 years (41.4-43.3). The adjusted risk for both retinopathy (hazard ratio 1.263 [95% CI 1.078-1.481]) and nephropathy (1.359 [1.228-1.504]) was higher in patients with diabetes and CD versus those without CD. Cox regression revealed CD as an independent risk factor for microvascular complications after adjustment for confounders. CONCLUSIONSCD is an independent risk factor for retinopathy and nephropathy in patients with type 1 diabetes. Our study therefore supports the recommendation for regular serologic testing for CD, even in the absence of clinical CD. Further prospective studies are required to investigate whether a gluten-free diet might reduce the risk of microvascular disorders in patients with diabetes and CD.

In addition to the well-known X-linked and autosomal recessive forms of aqueduct stenosis with hydrocephalus, this malformation can occur in other diseases with Mendelian inheritance. This finding is of considerable importance for genetic counselling and prognosis.