Late infantile neuronal ceroid lipofuscinosis caused by a CLN6 homozygous mutation:One case report and the literature review / 中国实用儿科杂志

ABSTRACT

OBJECTIVE: To collect the clinical features and gene mutation types of children with neuronal ceroid lipofuscinosis(NCLs)in China,and to help to make genetic diagnosis of NCLs patients. METHODS: The clinical manifestations and examinations of one case with complaints of language disorder for 1.5 years,dyskinesia for 0.5 years and repeated convulsions for one week were collected,and literatures of NCLs from China were reviewed. RESULTS: The electroencephalogram(EEG)showed multiple spikes and slow-wave discharges bilaterally. The brain MRI scan showed high hyperintensities adjacent to the bilateral posterior horns of the lateral ventricles on T2-weighted images and broadened cerebellar fissures. The "leukoencephalopathies and symptomatic epilepsy" was diagnosed. The genetic analysis showed that the proband had a homozygous missense point mutation c.892 G>A(p.Glu298 Lys)(reference sequenceNM＿017882.2)in exon 7 of CLN6 and that both his parents were heterozygous for the mutation. The diagnosis of late infantile neuronal ceroid lipofuscinosis(LINCLs)was confirmed according to the clinical features and genetic analysis results. In CNKI,WANFANG and WIPP Databases,we reviewed the relevant domestic reports about NCLs(28 articles). A total of 3 cases of CLN6 gene mutation were reported,including 2 cases of LINCLs caused by heterozygous mutation and 1 case of JNCLs caused by homozygous mutation. Here we reported the first case of LINCLs caused by a CLN6 homozygous mutation in China. CONCLUSION: This is the first case of LINCLs caused by CLN6 homozygous mutation reported in China. Our report expands the genotype data for NCLs.The mutant genes reported in NCLs patients are CLN1,CLN2,CLN3,CLN5,CLN6 and CLN7,and the clinical manifestations are intractable epilepsy,decreased vision,decreased intelligence,mental and motor dysfunction,personality and behavior changes,and memory decline. A gene sequencing panel for investigating unexplained seizures,leukoencephalopathies and inherited metabolic disorder can help to make the diagnosis.