Pregnancy Complicated by 3-Hydroxy-3-Methylglutaryl-CoA Lyase Deficiency and Kaposiform Lymphangiomatosis

BACKGROUND: To describe pregnancy complicated by deficiency of 3-hydroxy-3-methylglutaryl–CoA (HMG-CoA) lyase, an inborn error of metabolism, and kaposiform lymphangiomatosis (KLA), a lymphatic anomaly with poor prognosis. CASE: A 24-year-old woman with known HMG-CoA lyase deficiency and KLA presented at 6 weeks of gestation with severe vomiting and dehydration. Her pregnancy was complicated by worsening lung disease, fetal growth restriction, anemia, thrombocytopenia, and gestational diabetes. She required parenteral nutrition and adjustments in immunosuppressive therapy. At 37 weeks, she underwent induction of labor and delivered a male infant weighing 2,790 g with reassuring Apgar scores. CONCLUSION: This case demonstrates that, with multidisciplinary management, patients with coexisting rare disorders can achieve successful pregnancy outcomes despite substantial maternal and fetal risks.