5-Oxoprolinase Deficiency and Epilepsy: A Report of Four Cases with New Clinical Findings and Clinical Diversity Even in the Same Family


Koseci B., Kara E., Burgac E., Kaplan I., KOR D., BULUT F. D., ...Daha Fazla

Molecular Syndromology, 2025 (SCI-Expanded, Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1159/000545609
  • Dergi Adı: Molecular Syndromology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Anahtar Kelimeler: 5-Oxoprolinase deficiency, Hemolytic anemia, OPLAH gen, Psychomotor retardation (PMR), Seizures
  • Çukurova Üniversitesi Adresli: Evet

Özet

Introduction: 5-Oxoprolinuria is primarily suggestive of genetic defects in two enzymes belonging to the gamma-glutamyl cycle in the glutathione metabolism: the glutathione synthetase and the 5-oxoprolinase. 5-Oxoprolinase deficiency is a sporadic autosomal recessive disorder of the gamma-glutamyl cycle, primarily caused by pathogenic variants in the OPLAH gene. Low levels of 5-oxoproline can normally be detected in urine, although high levels are a clue for diagnosing 5-oxoprolinase deficiency. The clinical picture is not well defined due to the limited number of cases. Some authors questioned whether it is a real inherited metabolic disorder or only a nonspecific biochemical finding. Nephrolithiasis, enterocolitis, PMR, and microcytic anemia are the well-known clinical symptoms and signs of 5-oxoprolinuria (pyroglutamic aciduria). Methods: We present 4 patients who were diagnosed with 5-oxoprolinuria that had different clinical symptoms and 3 out of 4 patients were siblings. Results: In this study, 2 female and 2 male patients with 5-oxoprolinase deficiency were included. There were different clinical findings in the same family. Patients had unreported clinical symptoms such as growth retardation and drug-resistant epilepsy. Conclusion: OPLAH gene mutations have been observed to cause different clinical findings in the same family. A correlation was found between urine 5-oxoproline levels and the severity of clinical findings.