Very-late-onset multiple Acyl-coenzyme a dehydrogenase deficiency with elevated GDF-15 and Aldolase: a case report.

A 72-year-old woman on sertraline and levothyroxine (Levoxyl) presented to clinic with progressive proximal > distal and left > right upper and lower extremity weakness. She had length-dependent paresthesias and sensory deficits. Aldolase was elevated but CK was normal. EMG/NCS showed myopathic motor units. Muscle biopsy revealed numerous muscle fibers with markedly increased lipid content. Additional bloodwork showed elevated plasma acylcarnitine species of all chain lengths, concerning for multiple acyl-CoA dehydrogenase deficiency (MADD), along with elevated Growth Differentiation Factor 15 (GDF-15). Metabolic and mitochondrial genetic testing followed by whole exome sequencing was negative. The patient started riboflavin 400 mg daily and improved from requiring a wheelchair to independent ambulation. She was diagnosed with very-late-onset riboflavin-responsive MADD. This case adds to the growing literature on the clinical heterogeneity of VLO-MADD, comments on the potential for non-genetic, pharmacologic triggers like sertraline, and highlights that GDF-15 and aldolase can be elevated with normal CK.