Development and Initial Validation of the Macrophage Activation Syndrome/Primary Hemophagocytic Lymphohistiocytosis Score, a Diagnostic Tool that Differentiates Primary Hemophagocytic Lymphohistiocytosis from Macrophage Activation Syndrome.

Objective: To develop and validate a diagnostic score that assists in discriminating primary hemophagocytic lymphohistiocytosis (pHLH) from macrophage activation syndrome (MAS) related to systemic juvenile idiopathic arthritis.

Study Design: The clinical, laboratory, and histopathologic features of 362 patients with MAS and 258 patients with pHLH were collected in a multinational collaborative study. Eighty percent of the population was assessed to develop the score and the remaining 20% constituted the validation sample.

Cognitive profile in spastic paraplegia with thin corpus callosum and mutations in SPG11.

Autosomal recessive hereditary spastic paraplegia with thinning of the anterior corpus callosum (ARHSP-TCC) due to mutations in SPG11 on chromosome 15q (MIM610844) is the single most common cause of ARHSP. It is characterized by slowly progressive paraparesis and peripheral neuropathy. Although cognitive impairment, sometimes diagnosed as mental retardation, is an almost invariable feature, the extent and specific neuropsychological features are not fully understood.

Anti-N-methyl-D-aspartate-receptor encephalitis in a four-year-old girl.

Anti-N-methyl-D-aspartate-receptor encephalitis is a recently identified autoimmune disorder. We report on a 4-year-old girl presenting with seizures after nonspecific viral-like symptoms, progressing to severe aphasia, upper limb dyskinesias, fluctuation in consciousness, and inability to walk. Anti-N-methyl-D-aspartate-receptor encephalitis should be included in the differential diagnosis of acute/subacute encephalitis in children.

POMT2 gene mutation in limb-girdle muscular dystrophy with inflammatory changes.

Defects in glycosylation of alpha-dystroglycan are associated with several forms of muscular dystrophies. Mutations in POMT2 gene have been identified in patients with congenital muscular dystrophy and brain involvement, either characterized by a Walker-Warburg/muscle-eye-brain phenotype, or by microcephaly, mental retardation, and cerebellar hypoplasia. We identified a POMT2 homozygous missense mutation in a girl with a mild limb-girdle muscular dystrophy (LGMD) phenotype, marked elevated serum creatine kinase levels, and absence of brain involvement.

Phenotypic characterization of hypomyelination and congenital cataract.

Objective: To define the clinical and laboratory findings in a novel autosomal recessive white matter disorder called hypomyelination and congenital cataract, recently found to be caused by a deficiency of a membrane protein, hyccin, encoded by the DRCTNNB1A gene located on chromosome 7p21.3-p15.3.

Deficiency of hyccin, a newly identified membrane protein, causes hypomyelination and congenital cataract.

We describe a new autosomal recessive white matter disorder ('hypomyelination and congenital cataract') characterized by hypomyelination of the central and peripheral nervous system, progressive neurological impairment and congenital cataract. We identified mutations in five affected families, resulting in a deficiency of hyccin, a newly identified 521-amino acid membrane protein. Our study highlights the essential role of hyccin in central and peripheral myelination.