[Progressive cavitating leukoencephalopathy: four cases and literatures review]

Objective: To analyze the clinical and genetic features of progressive cavitating leukoencephalopathy (PCL). Method: The data of clinical and genetic features of 4 PCL patients diagnosed by Beijing Children's Hospital between January 2015 and January 2016 were analyzed. The cases with complete clinical data retrieved on literature search at China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform and PubMed (up to August 2016) by using search terms of"NDUFV1" ,"NDUFS1" , or"leukoencephalopathy" , were summarized. Result: There were three females and one male, two of which were compatriots. The age of onset ranged from 6 months to 15 months. All four children's first symptoms were motor development regression, and the developmental milestones were almost normal before the onset. Of the 4 patients, 3 had cognitive impairment, 1 had seizures, 4 had dystonia and pyramidal impairment, 2 had emaciation, and 1 had nystagmus. The lactate concentrations of 4 patients were normal in blood. One patient had lactaciduria in the urinary organic acid analysis. Cranial magnetic resonance imaging (MRI) of all patients showed leukoencephalopathy, involved in the corpus callosum, and three patients accompanied by cystic lesions. Follow up for 2-13 years showed that the physical and language development were improved. Genetic analysis revealed that mutations in NDUFS1 were found in three patients and NDUFV1 mutation was found in one patient. All six mutations (p.Arg377Cys and p. Arg377His in NDUFV1; p. Arg482Glyfs(*)5, p.Thr368Pro, p.Tyr454X and p. Asp565Gly in NDUFS1) are novel. Five English case reports including 10 PCL patients were collected. Together with this group of 4 cases, a total of 14 cases were involved. All 14 children patients had motor development regression, 11 cases had cognitive impairment and dystonia, 6 cases had pyramidal impairment, 5 cases had irritability, 4 cases had epilepsy and nystagmus, 3 cases had strabismus and swallowing difficulty. Cranial MRI showed patchy leukoencephalopathy with cavities, involved in the corpus callosum. Follow up for 19 months-15 years that the neurology development were improved slowly in all patients. Conclusion: NDUFS1 and NDUFV1 gene mutation screening should be performed firstly in patients with PCL clinical and imaging feature.