Yang Bao patient , male , age 8 ,2012 -10-29 treatment. 3 years old to walk, still can not speak , only no destination is called , since the laugh , often bow to walk , life can not take care of themselves , do not know who , abnormal behavior , often while biting his right hand fingers, tapping with the left hand side of the body , I do not know with people play . Mother during pregnancy is no different, full-term birth . No special family history . Physical examination: good move, aimless running around , head appear before the triangle. High performance liquid chromatography - tandem mass spectrometry examination results citrulline (Cit52.9 ↑), glutamate / citrulline ratios : Glu / Cit 1.7 ↓. Liver and kidney function : alkaline phosphatase (ALP) 180 ↑, glandular dehydrogenase (ADA) ↑, blood urea nitrogen (BUN) 8.47 ↑, carbon dioxide (CO2-CP) 31 ↑, uric acid (UA) 477 ↑, β2 microspheres protein (β2-MG) 3.88 ↑. MRI: bilateral frontal poor leaf development . Because they do not fit unmeasured IQ. According to clinical manifestations judged as very severe behavioral disorders associated with mental retardation .
The final diagnosis: citrullinemia induced behavioral disorders associated with mental retardation
Discuss
Citrullinemia (citrullinemia, OMIM215700), by the McMurray et al ( 1963 ) found , is an autosomal recessive genetic disease, as arginyl acid enzyme deficiency , the enzyme gene is located on 9q34-qter. Metabolites in the body produce toxic effects on the human body of ammonia , ammonia through the urea cycle or ornithine cycle and detoxification. When urea cycle disorders can produce hyperammonemia . Urea cycle process requires six kinds of enzymes involved in , any of which can cause an enzyme defect urea cycle disorder caused by hyperammonemia . Under normal circumstances , citrulline and aspartate to form argininosuccinate . When argininosuccinate cleavage enzyme deficiency can not occur , then the accumulation of citrulline and ammonia to form citrullinemia pathological damage incurred , resulting in disease. The disease is divided into classic type Ⅰ and Ⅱ .
Citrullinemia type Ⅰ mostly onset shortly after birth , including feeding difficulties , frequent vomiting, convulsions , movement disorders , more than half survived the initial attack does not exceed 17 months , and ultimately died of cerebral edema, mostly in the infant deaths.
Citrullinemia usually in adult-onset type 2 , primarily affects the nervous system . Features include a mental disorder , abnormal behavior ( such as aggressive , allergies and hyperactivity ) , seizures and coma. More than before the onset of stress , infections, alcohol or food intake a lot of protein and other incentives , the disease progresses rapidly into a coma , also can be deadly.
The clinical features of children : severe mental retardation , mental and behavioral disorders, facial features appear before the head triangle, but early childhood feeding conditions and physical symptoms is unknown. The few cases reported in the literature of different higher cognitive dysfunction is prominent intellectual and mental disorders based. Visible genetic disease phenotype can vary greatly , which has a high degree of heterogeneity, clinicians should pay attention to .
The clinical diagnosis of the disease lack of clinical specificity , mainly by blood, urine levels of citrulline , arginine exception. Etiological diagnosis based succinic acid arginyl decreased activity , and genetic testing .
To reduce high blood ammonia toxic effects on the nervous system , shall be permanently adhere to a low -protein diet can give sodium benzoate , sodium phenylacetate reduce ammonia and symptomatic treatment. Arginine may improve mitochondrial urea cycle enzyme activity , it can also be used to reduce ammonia . The only effective treatment is still liver transplantation , but the quality of life for patients with post-transplant time and lack of relevant research, so the effect is hard to evaluate for liver transplantation .
No comments:
Post a Comment