CSF non-protein nitrogen

Plasma non-protein nitrogen (NPN) compounds refer to a variety of nitrogen-containing substances in addition to various proteins. It includes urea, uric acid, creatine, amino acids, peptides, nucleotides, ammonia, and the like. Among them, the highest urea content, followed by amino acids and uric acid, creatinine and so on. Since most non-protein nitrogen compounds are intermediates in various protein metabolisms, they are more important than plasma proteins when determining the state of protein breakdown. Currently, non-protein nitrogen compounds commonly tested in the clinic include urea, creatinine, uric acid, amino acids and ammonia. Mainly used for evaluation of renal function, liver function, nucleic acid metabolism and nutritional status. Basic Information Specialist classification: examination classification: cerebrospinal fluid examination Applicable gender: whether men and women apply fasting: fasting Warm reminder: During the measurement process, all kinds of equipment and distilled water should be free of ammonia ion pollution, otherwise the result will be high. Normal value Urea nitrogen 2.1 ~ 5.4mmol / L (6 ~ 15mg / dl); Amino acid nitrogen 0.71 ~ 2.9mmol / L (1 ~ 4mg / dl); Children with uric acid 17.8～89.2μmol/L (0.30～1.5mg/dl); Adult 14.9 ~ 59.5μmol / L (0.25 ~ 1.0mg / dl); Creatinine 39.8 ~ 133μmol / L (0.45 ~ 1.5mg / dl). Clinical significance Elevated in meningitis, encephalitis, brain sclerosis, brain tumors, paralytic dementia, nephritis, uremia, liver disease, etc. High results may be diseases: uremia, nephritis, meningitis, paralytic dementia, sporadic encephalitis precautions (1) During the measurement process, all equipment and distilled water should be free of ammonia ion pollution, otherwise the result will be high. (2) The specimen is preferably serum. (3) The increase of blood ammonia can make the urea nitrogen result higher. Hemolysis specimens interfere with the assay. (4) Those who eat high protein diets are higher. Inspection process (1) Diacetyl-hydrazine method: 1 test tube marked blank tube "B", measuring tube "U", standard tube "S". 2 Add 20 μl of cerebrospinal fluid to the measuring tube, add 20 μl of standard tube plus standard application solution, and add 20 μl of distilled water to the blank tube. 3 3 ml of an acidic reagent and 3 ml of a diacetyl-hydrazine reagent were added. 4 Mix well, boil and heat for 10 minutes, remove and cool. 5520nm wavelength, blank tube zero colorimetric, read standard tube and measuring tube absorbance. (2) Enzyme coupling rate method: the reagent sample ratio was 70:1, 37 ° C, 340 nm, the lag time was 30 s, and the reading time was 30 s. The specific analysis conditions can be determined according to the specifications of the kit and the instrument, preferably every time. Not suitable for the crowd 1. If there is obvious papilledema or cerebral palsy, contraindications are contraindicated. 2. Patients who are in shock, exhaustion or endangered state and local skin inflammation, and lesions in the posterior cranial fossa are contraindicated. Adverse reactions and risks If the patient has symptoms such as breathing, pulse, or abnormal color during puncture, stop the operation immediately and deal with it accordingly.