Novel HPD mutation causes A new transient form of Hawkinsinuria? Case report

Background: Hawkiniuria is a rare group of autosomal dominant tyrosine metabolic diseases, usually caused by HPD gene mutations. So far, only a few cases of Hawkiniuria have been reported due to HPD gene mutations, and clinical symptoms usually resolve spontaneously around the age of 1 year. Case report Dizygotic twins were screened in 4 days old for inherited metabolic diseases using gas chromatography-tandem mass spectrometry (GC–MS/MS), and the elevated tyrosine in the blood and significantly elevated 4-hydroxyphenylpyruvate, 4-hydroxyphenyllactic acid and 4-hydroxyphenylacetic acid in the urine were significantly increased. At follow-up, the twins' blood tyrosine and urine levels of hawkinsin metabolites dropped significantly to normal levels at 80 days without special intervention. A new mutation in the HPD gene was found in the patient, the first time it has been found in the Chinese population. Conclusion: A new missense mutation of HPD gene has been detected in 2 cases of children diagnosed as hawkinsinuria, which is a possible pathogenic mutation and has not been reported at home and abroad. The clinical manifestations of the patients we reported are also different from previous literature reports. Our case enriches the clinical manifestations and gene mutation spectrum of hawkinsinuria, providing new insights for further research on hawkinsinuria.