HSD17B4 and hyperinsulinemic hypoglycemia, familial, 4: We present the case of an infant with elevated lysophosphatidylcholine C26:0 (C26:0-LPC) levels identified during X-linked adrenoleukodystrophy (ALD) screening, leading to a diagnosis of DBP deficiency due to a homozygous HSD17B4 c.1041T>A, p.(Tyr347Ter) variant.