A family of cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy

Objective To investigate the clinical features, imaging features, pathological features and gene diagnosis of cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL). Methods Clinical manifestations, signs and imaging characteristics of a female patient hospitalized in the First Affiliated Hospital of Zhengzhou University for more than 10 days due to headache were analyzed, and skin biopsy and HTRA1 and Notch3 gene detection were performed. The pedigree of the proband was investigated in detail, and HTRA1 gene test and related imaging examination were conducted in parallel. Due to the deceased parents of the patient, relevant genetic testing could not be conducted. A control group of 100 healthy people were analyzed. Results The clinical manifestations of proband were headache after insomnia, hearing loss in the right ear, easy to wake up and sweat at night. Brain MRI showed diffuse patchy long T1 and long T2 signals in bilateral fronto-parietal temporal occipital insula, internal and external capsule areas, bilateral basal ganglia areas, and bilateral thalamus. Fluid attenuated inversion recovery sequence showed high signals. Magnetic sensitive weighted imaging showed scattered patchy low signals in bilateral cerebral and cerebellar hemispheres, bilateral basal ganglia area, left thalamus and brain stem. The proband had consanguineous parents. A homozygous mutation C to T transition at position 589 (c.589C>T) was found in exon 3 of HTRA1 gene with the proband and both siblings. The heterozygous c.589C>T mutation appeared in another sister of the proband. Under the light microscope of skin biopsy, pigmentation in the basal layer of the skin could be seen, collagen fiber hyperplasia in the dermis was accompanied by a small amount of inflammatory cell infiltration, and no definite amyloidosis was found. No mutations were found in Notch3 gene. Because the patient′s parents were deceased, genetic testing was not possible. One hundred healthy controls had no such mutation. Conclusions The CARASIL family with HTRA1 gene c.589C>T homozygous mutation was reported, and the pathogenicity of the mutation was confirmed. HTRA1 genetic testing is recommended for diagnosis and differential diagnosis of CARASIL with family history or clinical suspicion. Key words: Cerebrovascular disorders; Genetic testing; Mutation; Pedigree; CARASIL; HTRA1 gene