Overview
NARP syndrome, characterized by neurogenic weakness, ataxia, and retinitis pigmentosa, results from mutations in mitochondrial DNA, notably the T8993G mutation, leading to impaired oxidative phosphorylation and associated clinical manifestations 1.Diagnosis
Genetic Testing: Identification of the T8993G mtDNA mutation 1.
Muscle Biopsy: Evidence of muscle ATPase deficiency 1.
Laboratory Tests: Measurement of plasma citrulline levels, often found to be hypocitrullinaemic 1.Management
Supportive Care: Physical therapy for ataxia and muscle weakness 1.
Nutritional Support: Addressing potential deficiencies due to impaired intestinal ATP production 1.
Monitoring: Regular ophthalmologic evaluations for retinitis pigmentosa progression 1.Special Populations
No Specific Data: Limited information provided regarding pregnancy, pediatrics, elderly, or comorbidities 1.Key Recommendations
Consider genetic testing for the T8993G mtDNA mutation in patients presenting with neurogenic weakness, ataxia, and retinitis pigmentosa (Evidence: Moderate) 1.
Evaluate plasma citrulline levels to identify hypocitrullinaemia, indicative of impaired oxidative phosphorylation in the small intestine (Evidence: Moderate) 1.
Implement supportive therapies including physical therapy and nutritional support tailored to individual needs (Evidence: Expert opinion) 1.References
1 Parfait B, de Lonlay P, von Kleist-Retzow JC, Cormier-Daire V, Chrétien D, Rötig A et al.. The neurogenic weakness, ataxia and retinitis pigmentosa (NARP) syndrome mtDNA mutation (T8993G) triggers muscle ATPase deficiency and hypocitrullinaemia. European journal of pediatrics 1999. link