Botulinum Toxin-A Injection in the Treatment of Spasticity in a Infantile-Onset Neurodegeneration With Brain Iron Accumulation: A Case Report

Pantothenate kinase-associated neurodegeneration (PKAN) is a neurodegenerative disorder characterized by iron accumulation in the globus pallidus (GP) of the brain (neurodegeneration with brain iron accumulation [NBIA]), which is characterized by dystonia and spasticity resulting in postural difficulties. A 33-month-old boy was admitted with a pronounced gait disturbance. Marked hypertonicity in the patient's both calf muscles was noted, resulting in waddling with repeated slip-falls. NBIA was suspected by high T2 intensity in the GP on brain MRI, then it was confirmed by detecting PANK2 mutation. Botulinum toxin-A injection was administered to both calf muscles. After 2 weeks, a decrease in spasticity and an increase in range of motion were observed, and consequently, an increase in the patient's gait stability with both heels touching the ground, enabling him to walk straight independently. A definitive treatment for NBIA has not been established, and a symptomatic therapy is currently the mainstay of treatment in this case. This is the first case report of botulinum toxin injection for treatment of gait disturbance caused by spasticity in an infantile-onset PKAN.

Phenotypic and genotypic features of twenty children with classic pantothenate kinase-associated neurodegeneration / 中华儿科杂志

Objective@#To explore the phenotypic and genotypic characteristics in Chinese children with classic pantothenate kinase-associated neurodegeneration (PKAN).@*Method@#The clinical, radiographic and genetic data of all PKAN patients diagnosed at pediatric department of Peking University First Hospital from November 2006 to December 2016 were retrospectively collected and analyzed.@*Result@#Twenty patients with classic PKAN were included in the study. The median age at onset was 3.5 years (ranging from 1.0 to 10.0 years), and the most common initial symptom was gait disturbance (16 cases). At the last evaluation, the clinical features were limbs dystonia (20 cases), dysarthria (16 cases), dysphagia (11 cases), pyramidal sign (7 cases), mental regression (3 cases) and pigmentary retinopathy (5 cases). For those classic PKAN patients, the median time from onset of disease to loss of independent ambulation was 6.9 years (ranging from 2.0 to 12.0 years). Imaging data showed, except "eye of tiger" in MRI (19 cases), globus pallidus calcification in CT was also found in four patients. In gene testing, 26 different mutations in PANK2 gene were identified, and 16 of 26 were novel mutations. Moreover, c. 1502T>C (p.Ile501Asn) was the most common mutation (4 cases).@*Conclusion@#Dystonia is the major neurologic feature of classic PKAN. Disease progression is rapid, with loss of independent ambulation within 10 years after onset. Except "eye of tiger" in MRI, globus pallidus calcification in CT may be another imaging feature of PKAN.Sixteen novel mutations of PANK2 gene were identified in the study.

Clinical Heterogeneity of Atypical Pantothenate Kinase-Associated Neurodegeneration in Koreans

OBJECTIVE: Neurodegeneration with brain iron accumulation (NBIA) represents a group of inherited movement disorders characterized by iron accumulation in the basal ganglia. Recent advances have included the identification of new causative genes and highlighted the wide phenotypic variation between and within the specific NBIA subtypes. This study aimed to investigate the current status of NBIA in Korea. METHODS: We collected genetically confirmed NBIA patients from twelve nationwide referral hospitals and from a review of the literature. We conducted a study to describe the phenotypic and genotypic characteristics of Korean adults with atypical pantothenate kinase-associated neurodegeneration (PKAN). RESULTS: Four subtypes of NBIA including PKAN (n = 30), PLA2G6-related neurodegeneration (n = 2), beta-propeller protein-associated neurodegeneration (n = 1), and aceruloplasminemia (n = 1) have been identified in the Korean population. The clinical features of fifteen adults with atypical PKAN included early focal limb dystonia, parkinsonism-predominant feature, oromandibular dystonia, and isolated freezing of gait (FOG). Patients with a higher age of onset tended to present with parkinsonism and FOG. The p.R440P and p.D378G mutations are two major mutations that represent approximately 50% of the mutated alleles. Although there were no specific genotype-phenotype correlations, most patients carrying the p.D378G mutation had a late-onset, atypical form of PKAN. CONCLUSIONS: We found considerable phenotypic heterogeneity in Korean adults with atypical PKAN. The age of onset may influence the presentation of extrapyramidal symptoms.

Déficit de pantotenato quinasa asociado a neurodegeneración: reporte de un caso clásico y revisión de la literatura / Pantothenate kinase-associated neurodegeneration: a classical case report and literature review

El déficit de pantotenato quinasa asociado a neurodegeneración (PKAN por su sigla en inglés) es una enfermedadneurodegenerativa poco frecuente que se caracteriza por disfunción extrapiramidal progresiva y acumulaciónde hierro en los ganglios basales. El signo clásico en la neuroimagen de “ojos de tigre” se ve en las imágenesponderadas en T2 en la resonancia magnética cerebral. A continuación presentamos un caso clásico de la enfermedaden un niño que inicia con síntomas motores a los 5 años de edad y que fue estudiado en el Instituto deOrtopedia Infantil Roosevelt, con neuroimágenes típicas y confirmación de la mutación por estudio molecular.

Pantothenate kinase-associated neurodegeneration (PKAN) is a rare neurodegenerative disease characterized by progressive extrapyramidal dysfunction and iron accumulation in the basal ganglia. The classic sign in neuroimaging of "eye of the tiger" is seen on T2-weighted magnetic resonance imaging scan. We present a classic case of the disease in a child who starts with motor symptoms at 5 years old and was studied at the Instituto de Ortopedia Infantil Roosevelt, with typical neuroimaging and confirmation of the mutation by molecular study.

A Case of Retinal Pigmentary Degeneration in PKAN

PURPOSE: Pantothenate kinase-associated neurodegeneration (PKAN), also known as neurodegeneration with brain iron accumulation is an extremely rare degenerative disease. The present study reports a case of retinal pigmentary changes in PKAN. CASE SUMMARY: A 6-year-old girl presented with night blindness and developmental delay. Neurologic examination revealed toe gait and dystonia. Ocular examination showed retinal pigmentary change in the entire retina without optic atrophy. Brain magnetic resonance imaging showed iron deposits in the basal ganglia, the so-called "eye of the tiger" sign. Genetic tests confirmed a mutation in the gene encoding pantothenate kinase 2. Electroretinography demonstrated severe loss of rod and cone responses, prominently reduced in the rod response. The patient was diagnosed with PKAN and pharmacologic treatment started. CONCLUSIONS: In the case of systemic neurological abnormalities with pigmentary retinal change, PKAN should be considered as a differential diagnosis.

A Novel PANK2 Mutation in a Patient with Atypical Pantothenate-Kinase-Associated Neurodegeneration Presenting with Adult-Onset Parkinsonism

BACKGROUND: Pantothenate-kinase-associated neurodegeneration (PKAN) is an autosomal recessive neurodegenerative disorder that is characterized by progressive extrapyramidal signs, visual loss, and cognitive impairment. PKAN is caused by mutations in the pantothenate kinase gene (PANK2), which is located on chromosome 20p13 and encodes pantothenate kinase, the key regulatory enzyme in coenzyme-A biosynthesis. CASE REPORT: In this report we describe a case of atypical PKAN with a novel PANK2 mutation, presenting with a 10-year history of postural tremor involving both hands. Upon neurological examination, the patient's face was masked and he spoke in a monotonous voice. The patient presented with mild bradykinesia and rigidity that involved all of the extremities. Horizontal saccadic eye movements were slow and fragmented. Brain MRI revealed a typical "eye-of-the-tiger" sign. A mutation analysis revealed three PANK2 mutations: two in exon 3 (Asp 378Gly and Leu385CysfsX13) and one in exon 4 (Arg440Pro). CONCLUSIONS: Parkinsonism is not an unusual presenting symptom in patients with atypical PKAN, and so it is important for physicians to consider PKAN in the differential diagnosis of patients presenting with young-onset parkinsonism.