Biotinidase deficiency: A treatable cause of hereditary spastic paraparesis.
    
    
        
    
    
        
        Neurol. Genet. 6:e525 (2020)
    
    
    
      
      
	
	    ObjectiveTo expand the genetic spectrum of hereditary spastic paraparesis by a treatable condition and to evaluate the therapeutic effects of biotin supplementation in an adult patient with biotinidase deficiency (BD).MethodsWe performed exome sequencing (ES) in a patient with the clinical diagnosis of complex hereditary spastic paraparesis. The patient was examined neurologically, including functional rating scales. We performed ophthalmologic examinations and metabolic testing.ResultsA 41-year-old patient presented with slowly progressive lower limb spasticity combined with optic atrophy. He was clinically diagnosed with complex hereditary spastic paraparesis. The initial panel diagnostics did not reveal the disease-causing variant; therefore, ES was performed. ES revealed biallelic pathogenic variants in the BTD gene leading to the genetic diagnosis of BD. BD is an autosomal recessive metabolic disorder causing a broad spectrum of neurologic symptoms, optic atrophy, and dermatologic abnormalities. When treatment is initiated in time, symptoms can be prevented or reversed by biotin supplementation. After diagnosis in our patient, biotin supplementation was started. One year after the onset of therapy, symptoms remained stable with slight improvement of sensory deficits.ConclusionsThese findings expand the genetic spectrum of the clinical diagnosis of complex hereditary spastic paraparesis by a treatable disease. Today, most children with BD should have been identified via newborn screening to start biotin supplementation before the onset of symptoms. However, adult patients and those born in countries without newborn screening programs for BD are at risk of being missed. Therapeutic success depends on early diagnosis and presymptomatic treatment.
	
	
	    
	
       
      
	
	    
		Impact Factor
		Scopus SNIP
		Web of Science
Times Cited
		Scopus
Cited By
		Altmetric
		
	     
	    
	 
       
      
     
    
        Publication type
        Article: Journal article
    
 
    
        Document type
        Scientific Article
    
 
    
        Thesis type
        
    
 
    
        Editors
        
    
    
        Keywords
        
    
 
    
        Keywords plus
        
    
 
    
    
        Language
        english
    
 
    
        Publication Year
        2020
    
 
    
        Prepublished in Year
        
    
 
    
        HGF-reported in Year
        2020
    
 
    
    
        ISSN (print) / ISBN
        2376-7839
    
 
    
        e-ISSN
        2376-7839
    
 
    
        ISBN
        
    
    
        Book Volume Title
        
    
 
    
        Conference Title
        
    
 
	
        Conference Date
        
    
     
	
        Conference Location
        
    
 
	
        Proceedings Title
        
    
 
     
	
    
        Quellenangaben
        
	    Volume: 6,  
	    Issue: 6,  
	    Pages: ,  
	    Article Number: e525 
	    Supplement: ,  
	
    
 
    
        
            Series
            
        
 
        
            Publisher
            American Academy of Neurology
        
 
        
            Publishing Place
            Minneapolis, Minn.
        
 
	
        
            Day of Oral Examination
            0000-00-00
        
 
        
            Advisor
            
        
 
        
            Referee
            
        
 
        
            Examiner
            
        
 
        
            Topic
            
        
 
	
        
            University
            
        
 
        
            University place
            
        
 
        
            Faculty
            
        
 
    
        
            Publication date
            0000-00-00
        
 
         
        
            Application date
            0000-00-00
        
 
        
            Patent owner
            
        
 
        
            Further owners
            
        
 
        
            Application country
            
        
 
        
            Patent priority
            
        
 
    
        Reviewing status
        Peer reviewed
    
 
     
    
        POF-Topic(s)
        30501 - Systemic Analysis of Genetic and Environmental Factors that Impact Health
30205 - Bioengineering and Digital Health
    
 
    
        Research field(s)
        Genetics and Epidemiology
    
 
    
        PSP Element(s)
        G-500700-001
G-503200-001
    
 
    
        Grants
        German Federal Ministry of Education and Research (BMBF, Bonn, Germany)
    
 
    
        Copyright
        
    
 	
    
    
    
    
        Erfassungsdatum
        2021-02-04