PHARC (Polyneuropathy, Hearing Loss, Ataxia, Retinitis Pigmentosa and Cataract) - A Case Report and Clinical-Focused Literature Review.

Polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract (PHARC) is a rare condition caused by mutations in ABHD12. We present the first documented case of PHARC in a Brazilian patient. Describe the clinical and genetic aspects of patients diagnosed with PHARC through a literature review. A literature review was conducted in February 2024 using Pubmed/Medline database. We also report a 37-year-old Brazilian woman diagnosed with PHARC. Between 38 patients diagnosed with this condition, the majority were male (74.35%) and the median age was 35.7 years. The most common symptom reported was ataxia (79.4%). The main finding of Brain MRI was cerebellar atrophy, and demyelinating polyneuropathy was the commonest finding in electroneuromyography, both were found in 28.2% of patients. PHARC syndrome is a rare autosomal recessive condition that is increasingly reported in the literature. Refsum disease and Usher syndrome are the main differential diagnosis. A multidisciplinary approach and follow-up are crucial for accurate diagnosis and treatment.