成人苯丙酮尿症一例

A case report of adult phenylketonuria and literature review

目的探讨成人苯丙酮尿症(PKU)的病因、临床表现、影像学特点。方法分析1例成人PKU的临床表现、影像学表现、检查及治疗结果。结果本例成人PKU患者主要表现为行走不稳、智力减退,影像学表现主要为双侧脑室旁脱髓鞘。查血液苯丙氨酸浓度升高,尿液蝶呤检测提示6-丙酮酰四氢生物蝶呤合成酶缺乏。按PKU给予低苯丙氨酸饮食,对症支持治疗。随诊7年时,患者血液苯丙氨酸水平正常,但患者临床症状及头颅影像学与入院时比较无明显变化。结论 PKU起病隐匿,临床表现多样,常引起不可逆的中枢神经系统脱髓鞘改变。新生儿疾病筛查虽然是重要诊断手段,但还需对PKU进行鉴别诊断及分型,并根据分型采取不同治疗方法,改善患者预后。

Objective To summarize on the clinical feature of adult phenylketonuria(PKU).Method Retrospective analysis the pathogenesis,clinical presentation,and imaging manifestations of an adult PKU case.Results The patient is mainly characterized by walking instability and mental retardation.MRI brain scan shows demyelinating lesions rounded mainly in bilateral periventricular white matter.Laboratory tests reveal an accumulation of phenylalanine in serum,urinary neopterin and biopterin ananlysis shows the deficiency of 6-pyruvoyltetrahydropterin synthase(PTPS).The treatment included maintaining a diet with low levels of phenylalanine and symptomatic treatment.The followed-up time was 7 years,the patient's blood phenylalanine concentration in serum is normal.But the patient's clinical symptoms and brain MRI were not improved.Conclusion Phenylacetone urine disease clinical manifested varied,and often caused irreversible demyelinating in central nervous system.Although neonatal disease screening is an important diagnostic method,the differential diagnosis and classification of PKU shouldn't be ignored.Different treatment methods should be adopted according to type.