ZASP/LDB3-related atypical distal myopathy with subtle cardiac impairment unveiled after COVID-19 infection: a short report.

Abstract

Case presentation: A 34-year-old male with congenital clubfoot, post-exertional rhabdomyolysis, and a family history of sudden cardiac death in mid-life was evaluated for a severe rhabdomyolysis requiring multiple hemodialyses. Clinical evaluation showed mild distal myopathy signs, with CK levels around 3000 IU/L and muscle biopsy revealing desmin- and dystrophin-positive cytosolic protein aggregates/fibre splitting. After a minor SARS-CoV-2 infection at 55, modest signs of cardiomyopathy were observed via cardiac MRI, without patterns indicative of myocarditis. Subsequently, NGS analysis identified a variant in the LDB3 gene, potentially correlated with the clinical-histological-radiological picture, thus broadening the phenotypic spectrum of LDB3-related distal myopathies. Additionally, a possible link was suggested between the viral infection and the exacerbation of the otherwise subtle cardiomyopathy. In the context of hyperCKemia and positive family history for unexplained cardiac abnormalities, broad-spectrum NGS testing, and cardiac MRI in selected cases, should be considered for timely diagnosis and interventions.