Christian Denier1, Laurent Balu2, Béatrice Husson3, Ghaidaa Nasser3, Lydie Burglen4, Diana Rodriguez5, Pierre Labauge6, Laurent Chevret7. 1. Department of Neurology, Bicêtre Hospital, Assistance-Publique-Hôpitaux de Paris (AP-HP), France. Electronic address: christian.denier@bct.aphp.fr. 2. Department of Pediatry, Bicêtre Hospital, Assistance-Publique-Hôpitaux de Paris (AP-HP), France. 3. Department of Radiology, Bicêtre Hospital, Assistance-Publique-Hôpitaux de Paris (AP-HP), France. 4. Department of Genetics, Trousseau Hospital, AP-HP, France. 5. Department of Pediatry, Robert Debré Hospital, AP-HP, France. 6. Department of Neurology, Montpellier Hospital, France. 7. Department of Neurology, Bicêtre Hospital, Assistance-Publique-Hôpitaux de Paris (AP-HP), France.
Abstract
BACKGROUND: Acute necrotizing encephalopathy (ANE) is a rare and severe parainfectious central nervous system disease in which previously healthy children develop rapidly progressive coma following viral illness. While most ANE are sporadic, familial autosomal dominant ANE due to mutations in the RANBP2 gene has been recently reported (ANE1 or infection-induced acute encephalopathy-3 (IIAE3)). To date, only few IIAE3 families with ADANE episodes have been described. OBJECTIVE: To report a new family with ADANE, describe clinical and radiological features and discuss differential diagnosis including Leigh syndrome or multiple sclerosis. OBSERVATION: The family included 3 symptomatic individuals and one 59 year-old asymptomatic obligate carrier. Patients presented acute episodes of encephalopathy few days after common viral infection. Ages of onset ranged from 6 months to 5 years. Episodes not only occurred in childhood but also recurred in adulthood. Initial neurological signs included coma, focal neurological deficits and seizures. MRI showed typical necrotizing lesions primarily in the thalamus and brainstem, and in the temporal lobes and insula. CSF cell count and cultures were normal during episodes. RANBP2 gene screening identified pathogenic heterozygous c.1754C>T mutation (p.Thr585Met). Episodes led to cognitive or physical handicap in 2 patients and were fatal in one child. CONCLUSION: IIAE3 or ADANE due to RANBP2 mutations has a large clinical heterogeneity. Our family illustrates the associated phenotypes from asymptomatic carrier to severe episodes of encephalopathy. Based on MRI features, the genetic IIAE3 diagnosis is important since prophylaxis and symptomatic management of infections may be beneficial, possibly in association with steroid or gammaglobulins.
BACKGROUND: Acute necrotizing encephalopathy (ANE) is a rare and severe parainfectious central nervous system disease in which previously healthy children develop rapidly progressive coma following viral illness. While most ANE are sporadic, familial autosomal dominant ANE due to mutations in the RANBP2 gene has been recently reported (ANE1 or infection-induced acute encephalopathy-3 (IIAE3)). To date, only few IIAE3 families with ADANE episodes have been described. OBJECTIVE: To report a new family with ADANE, describe clinical and radiological features and discuss differential diagnosis including Leigh syndrome or multiple sclerosis. OBSERVATION: The family included 3 symptomatic individuals and one 59 year-old asymptomatic obligate carrier. Patients presented acute episodes of encephalopathy few days after common viral infection. Ages of onset ranged from 6 months to 5 years. Episodes not only occurred in childhood but also recurred in adulthood. Initial neurological signs included coma, focal neurological deficits and seizures. MRI showed typical necrotizing lesions primarily in the thalamus and brainstem, and in the temporal lobes and insula. CSF cell count and cultures were normal during episodes. RANBP2 gene screening identified pathogenic heterozygous c.1754C>T mutation (p.Thr585Met). Episodes led to cognitive or physical handicap in 2 patients and were fatal in one child. CONCLUSION:IIAE3 or ADANE due to RANBP2 mutations has a large clinical heterogeneity. Our family illustrates the associated phenotypes from asymptomatic carrier to severe episodes of encephalopathy. Based on MRI features, the genetic IIAE3 diagnosis is important since prophylaxis and symptomatic management of infections may be beneficial, possibly in association with steroid or gammaglobulins.
Authors: Kyoung-In Cho; Dosuk Yoon; Sunny Qiu; Zachary Danziger; Warren M Grill; William C Wetsel; Paulo A Ferreira Journal: Dis Model Mech Date: 2017-01-18 Impact factor: 5.758