P.360 - Misdiagnosis and diagnostic delay in McArdle disease

Abstract

Correct diagnosis is rarely identified before adulthood in McArdle Disease (GSDV). The frequency of misdiagnosis, duration of diagnostic delay, categories of misdiagnoses and inappropriate medical interventions were assessed in 50 genetically confirmed patients. Majority of the studied cases 90% (n = 45/50) received a misdiagnosis, most often during childhood years (67%; n = 30/45). Misdiagnosis also occurred during teenage years or adulthood (teenage: n = 7/45; adult n = 5/45; not known n = 3/45). The median age of a correct diagnosis was 33 years. Following misdiagnosis, almost half of the patients (47%, n = 21) received wrong treatment to include unnecessary surgeries, steroids, antibiotics and wrong exercise advice. A high frequency of misdiagnosis was seen in this study sample, giving further evidence that misdiagnosis plays an important role in GSDV diagnostic delay.