When the yellow hair encountered the taste of rat urine, it is the neurology of this disease? Do you know?

Today's nerve case time, we look at a common genetic metabolic disease in neurology, patients can be shown as low intelligence,epilepsy
seizures, behavioral abnormalities and other symptoms, but also as eczema, rat urine taste, skin white, hair light yellow dryness and other symptoms, the next time we encounter these symptoms of patients, we can handle it! Let's take a look at it ,patient male, 30 years old, because of intelligence down for more than 20 years, hands tremor 8 years admitted to the hospitalmore than 20 years ago, patients inwere found by their families to be inferior in intelligence compared to their peers, poor academic performance, no speech impairment, no abnormal mental behavior, no limb convulsions;Patients with yellow hair (undyed hair), the body has the taste of rat urinenervous system check body: clear mind, fluent speech, reduced computational powerCranial neurosciatic negativeThe muscle strength, muscletension of the limbsnormal, and there was no abnormality in the sensationBoth sides of the knee reflex ( , ) , pathological reflex escite , and the neck is softCranial BRAIN MRI DWI and T2WI show: two-sided ventricle side and rear corner of the brain white matter demyelin abnormal signalthree conventional, blood biochemical, trace elements, copper blue protein, thyroid function, rheumatism four, anti-nuclear antibody spectrum did not see abnormal Increased levels of blood phenylalanine (1350 ?mol/L) Organic uric acid analysis showed: benzene acetic acid-1, benzene lactic acid-2, phenyl ketone acid-OX-2 increase continue to eat a low phenylalanine diet and control protein, such as fish and meat intake, and control the intake of vegetables with high starch content, such as potatoes the patient was clinically diagnosed with phenylketonuria (phenylketonuria, PKU) at an early stage, what about the pathophysiological mechanism and imaging characteristics of PKU? Let's review what PKU is PKU is an autosomal recessive genetic disease, a congenital metabolic disease caused by a lack of phenylalanine hydroxyase in the liver The average incidence of Chinese hyperphenylalanineemia is about 1/11,000, most of which are PKU, according to the of neonatal screening The prevalence rate is equal for both men and women physiological mechanism
The mutation of the phenylalanine hydroxylase (phenylalalanine hydroxylase, PAH) gene mutation causes loss or significant decrease in PAH activity and the hydroxydeation reaction of phenylalanine is blocked Phenylalanine in the blood accumulates and is converted into phenylketonic acid and phenyleacetic acid through phenylalanine transaminase (1) In brain tissue, phenylalanine inhibits alysis of alykeic acid de-argonas, leading to myelin formation defects and intellectual retardation (2) Phenylalanine hydroxyis blocked caused benzene acetic acid, phenyl ketone acid excreted from the urine, the appearance of rat urine taste (3) Due to the phenylalanine hydroxyreaction is blocked, tyrosine reduction leads to a decrease in downstream products, resulting in white skin (reduced melanin synthesis) and neuropsychiatric symptoms (reduced neurotransmitter) Phenylalanine metabolism map clinical manifestations Common symptoms of PKU are low intelligence, seizures, abnormal behavior, eczema, rat urine taste, white skin, hair light yellow dryness and so on About 90% of children with moderate to severe mental retardation are most prominent with language disorders Cone and cone-in vitro changes can also occur, such as tremors, leg reflections, excessive or too little movement, etc In addition to neurological symptoms, mental symptoms are also prominent, including low self-esteem, depression, anxiety, fear, social disorders and so on imaging performance
PKU's main imaging performance is the abnormal signal of brain white matter, T2WI is a spot-like, strip-like non-occupancy high signal, commonly found in the side ventricle rear corner top pillow white matter With the progress of the disease extended forward, gradually tired of the two-sided ventricular body side by side white matter and side ventricular front corner side white matter, visual radiation is generally not tired Some scholars suggest that the abnormal signal of DWI brain white matter in PKU patients is related to the concentration of blood phenylalanine, that is, the higher the concentration of blood phenylalanine, the more obvious the dWI high signal Two-sided visual radiation retention (red arrow) diagnosis clinical diagnosis is based on the following two aspects: (1) biochemical testing: increased concentration of alanine in the blood, phenylalanine /tyrosine 2; (2) Clinical characteristics: common symptoms of PKU (see Clinical Manifestations) genetic diagnosis: In alleles of PKU mutations, 97% of the PAH gene defects are tiny mutations Large fragmentgene deletions or repeat mutations accounted for 1%-2%, the most common deletions occurred in the first exon and its upstream, the 6th exon and the fourth exon differential diagnosis X-chain adrenal white matter malnutrition: is an X-chain recessive genetic disease, mainly affecting the adrenal glands and brain white matter, more than half of the child or adolescent disease The main clinical manifestations were progressive mental movement disorders, vision and hearing loss, and low adrenal cortex function THE MRI FEATURES A "BUTTERFLY WING-LIKE" HIGH SIGNAL WITH A TWO-SIDED TOP PILLOW LEAF WHITE SYMMETRY DISTRIBUTION, WHICH IS DEVELOPED FROM BEHIND Iso-infective cerebral white matter malnutrition: is an autosomal recessive hereditary lysosome storage disease The main clinical manifestations are mental sensory movement swindle MRI is characterized by "tiger pattern" and "leopard spot sign", i.e a high-signal area of semi-egg center white matter lesions with a radioactively arranged line or dot-like low-signal area, while bearing on the knee and pressure of the carcass Carbon monoxide poisoning (CO) encephalopathy: toxic encephalopathy in carbon monoxide has a history of exposure Patients with late-onset encephalopathy disorders, after waking up with acute CO poisoning, developed neurological diseases mainly with dementia, mental symptoms and cone-in vitro abnormalities after a seemingly normal period of false recovery Brain white matter is common, most commonly in the semi-egg circle and the ventricular side-by-brain white matter, which is characterized by a high signal of two-sided symmetry or asymmetric T2WI Toxic encephalopathy in organic solvents: Benzene toxic encephalopathy often occurs in the use of chemicals containing benzene agents, such as paint or footwear manufacturing plants Benzene vapor is inhaled through the respiratory tract or is exposed to the skin MRI is characterized by the bruising of the cerebral white matter, the outer sac, the cerebellum toothed nucleus and pale spheres on both sides of the two-sided symmetry of the cerebral hemisphere, accompanied by varying degrees of brain swelling Treatment there is no cure for PKU, and the low phenylalanine diet is the main method of controlling PKU Through dietary control, some patients' intelligence levels can be close to normal A low phenylalanine diet needs to start in the neonatal period and last for life PKU patients need to strictly control protein intake, such as: fish, meat, eggs and dairy products, some low protein, high starch content of vegetables, such as: potatoes, peas, etc should also limit the intake Due to strict food control, patients need to supplement medical foods with essential amino acids, minerals, vitamins and trace elements summary Increased levels of phenylalanine after long-term or short-term low alanine diet interruption can complicate neurological symptoms in PKU patients Neurologists should understand PKU, in the presence of cranial nonspecific white matter lesions and neurological symptoms, should be timely measurement of phenylalanine, with a view to early intervention to improve the prognosis expert profile Shen Yaoyao Source: