Case Report: Early-onset mevalonic aciduria in neonates with inflammatory marker elevated

Purpose The aim of this study was to present a case of early-onset mevalonic aciduria (MA) in a neonate and summarize the relevant phenotypic and genotypic spectra of MA. Methods and results We describe a neonate who presented with elevated inflammatory marker after birth. Liver function tests revealed liver injury, and enzyme-linked immunosorbent assay (ELISA) confirmed increased mevalonic acid levels in blood and urine. Whole-genome sequencing identified a novel homozygous mutation (c.928G>A, p.Val310Met) in the MVK gene. To date, only 16 neonate cases of MA have been reported in the literature. Affected individuals typically present recurrent fever, hepatosplenomegaly, lymphadenopathy, vomiting, diarrhea, and neurological damage symptoms. This case emphasizes that in patients presenting with recurrent fever accompanied by vomiting, diarrhea, hepatosplenomegaly, and lymphadenopathy, clinicians should pay close attention to differentiating MA from infectious diseases and autoinflammatory disorders to avoid misdiagnosis or underdiagnosis. Conclusion We report one of the youngest neonates with early-onset MA diagnosed promptly, caused by the novel homozygous MVK variant, c.928G>A (p.Val310Met), and expand the genotypic and clinical phenotypic spectrum of MVK variants related with MA.