Prenatal clinical manifestations in individuals with COL4A1/2 variants.

BACKGROUND: Variants in the type IV collagen gene (COL4A1/2) cause early-onset cerebrovascular diseases. Most individuals are diagnosed postnatally, and the prenatal features of individuals with COL4A1/2 variants remain unclear. METHODS: We examined COL4A1/2 in 218 individuals with suspected COL4A1/2-related brain defects. Among those arising from COL4A1/2 variants, we focused on individuals showing prenatal abnormal ultrasound findings and validated their prenatal and postnatal clinical features in detail. RESULTS: Pathogenic COL4A1/2 variants were detected in 56 individuals (n=56/218, 25.7%) showing porencephaly (n=29), schizencephaly (n=12) and others (n=15). Thirty-four variants occurred de novo (n=34/56, 60.7%). Foetal information was available in 47 of 56 individuals, 32 of whom (n=32/47, 68.1%) had one or more foetal abnormalities. The median gestational age at the detection of initial prenatal abnormal features was 31 weeks of gestation. Only 14 individuals had specific prenatal findings that were strongly suggestive of features associated with COL4A1/2 variants. Foetal ventriculomegaly was the most common initial feature (n=20/32, 62.5%). Posterior fossa abnormalities, including Dandy-Walker malformation, were observed prenatally in four individuals. Regarding extrabrain features, foetal growth restriction was present in 16 individuals, including eight individuals with comorbid ventriculomegaly. CONCLUSIONS: Prenatal observation of ventriculomegaly with comorbid foetal growth restriction should prompt a thorough ultrasound examination and COL4A1/2 gene testing should be considered when pathogenic variants are strongly suspected.

A case of intraneural perineurioma presenting with monomelic atrophy in a child.

We report the case of an 11-year-old girl who developed slowly progressive atrophy of the left lower extremity. She suffered from mild dilated cardiomyopathy of unknown cause since 4years of age. When she was 7years old, her family noticed that her left extremity was thinner compared to the right one. Computed tomography showed atrophy and areas of low density in the left gluteus maximus, thigh, and calf muscles. The left sciatic nerve showed gadolinium enhancement on magnetic resonance imaging. A biopsy of the left sural nerve revealed pseudo-onion bulbs. Immunohistochemical staining was positive for epithelial membrane antigen and negative for S100 protein. Electron microscopy demonstrated myelinated or unmyelinated nerve fibers surrounded by concentric layers of perineurial cells. These results indicated intraneural perineurioma. The tumor was estimated at least from the nerve root to the ankle joint. The length of nerve involvement in this patient was the highest recorded in the literatures. Intraneural perineurioma is a very rare disorder, but is tend to be found in youth. This disorder should be considered when we see children with monomelic weakness and/or atrophy.

A case of X-linked agammaglobulinemia with progressive encephalitis.

This report describes a case of agammaglobulinemia with progressive encephalitis. The patient was a 6-year-old male who was diagnosed as having Bruton-type agammaglobulinemia at age 6 months. After the diagnosis was made, he received monthly intravenous immunoglobulin replacement with a residual immunoglobulin G level of more than 400 mg/dL. At 5 years of age, he presented with symptoms of mental deterioration and gait disturbance. He had no history of infection of the central nervous system. Brain biopsy revealed CD8-positive T-cell infiltration with cortical damage, but no infectious agents were observed by either immunohistochemistry or virus isolation. Treatment with subcutaneous interferon-alpha and high-dose intravenous immunoglobulin was begun, and clinical symptoms improved within a month. Hence, patients with agammaglobulinemia should be carefully monitored for complications of the central nervous system even if there is no history of infection.