A rare coexistence: tyrosinemia type III and Wolff–Parkinson–White syndrome


Yılmaz-Gümüş E., Genç E., Kocaman D., Şaylan-Çevik B., POLAT H., Arslan-Ateş E., ...Daha Fazla

Journal of Pediatric Endocrinology and Metabolism, 2026 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1515/jpem-2026-0078
  • Dergi Adı: Journal of Pediatric Endocrinology and Metabolism
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, EMBASE, MEDLINE
  • Anahtar Kelimeler: 4-hydroxyphenylpyruvate dioxygenase deficiency, hypertyrosinemia, tyrosinemia type III, Wolff–Parkinson–White syndrome
  • Marmara Üniversitesi Adresli: Evet

Özet

Objectives: Tyrosinemia type III is an extremely rare autosomal recessive disorder of tyrosine metabolism caused by mutations in the HPD gene, which encodes 4-hydroxyphenylpyruvate dioxygenase (HPPD). Wolff–Parkinson–White (WPW) syndrome is a congenital cardiac conduction disorder characterized by the presence of an accessory atrioventricular pathway. While each condition is rare in isolation, their coexistence has not been previously reported. Case presentation: We present a unique case of a 6-year-old boy with known WPW syndrome who was admitted with ketotic hypoglycemia after prolonged fasting and omission of propranolol doses. Metabolic work-up revealed persistently elevated plasma tyrosine levels. Genetic testing confirmed tyrosinemia type III due to a novel homozygous HPD variant [c.559A>G (p.Asn187Asp)]. The persistence of the WPW pattern despite decreased plasma tyrosine levels suggests that there is no direct causal relationship. He was also diagnosed with attention-deficit/hyperactivity disorder, specific learning disorder, and borderline intellectual functioning. Conclusions: This case highlights the importance of metabolic evaluation in pediatric patients presenting with unexplained hypoglycemia, particularly in the presence of preexisting cardiac disorders.