Nitrotetrazolium blue test

The energy consumption of neutrophils increases during the sterilization process. The hydrogen-reduced nitroblue tetrazolium in the metabolism becomes a blue-black dot or lumps deposited in the cytoplasm of granulocytes, and the positive rate is determined according to the intracellular sedimentary particles. . This test is mainly used to detect the intracellular killing function of neutrophils, and can be used to diagnose chronic granulomatosis in children and to identify bacterial and viral infections. Basic Information Specialist classification: inspection classification: immune examination Applicable gender: whether men and women apply fasting: fasting Analysis results: Below normal: Normal value: no Above normal: negative: 5% to 10% are negative for NBT. Positive: Normal people generally think that more than 10% are positive. Tips: This test is not specific, and is currently used for the screening of chronic granuloma and bacterial system infections. Normal value Normal people generally think that more than 10% are positive. 5% to 10% are negative for NBT. If NBT is negative, take 0.5ml heparin anticoagulant plus 10μg bacterial endotoxin and test according to the above method, such as NBT positive cells>29%, indicating that the neutrophil phagocytosis function of the subject is normal, if still 5 %~10% is a malfunction. Clinical significance Low values ​​of NBT are found in chronic granulomas, congenital propofol deficiency, lupus erythematosus, and the use of immunosuppressive agents. This method can also be used to distinguish between bacterial and viral infections. In the case of a viral infection, although there is fever, NBT is still normal; only bacteria and fungal infections, NBT positive cells increase. The NBT test can also be used for the differential diagnosis of febrile reactions after organ transplantation. If the fever occurs due to bacterial infection, the NBT value increases; however, if the fever occurs due to non-specific reaction in the body, the NBT value remains normal. Positive results may be diseases: pediatric chronic granulomatosis, faba bean disease, pediatric glucose-6-phosphate dehydrogenase deficiency, myeloperoxidase deficiency precautions (1) Heparin anticoagulation and NBT application solution are mixed in equal amounts and then incubated. The method of heat preservation is very important, and the reduction of NBT will be reduced in the water bath. (2) When counting, neutrophils and monocytes that are aggregated or ruptured are not counted. There are often piles of platelets adhering to neutrophils, paying attention to the difference. (3) The specificity of this test is not strong, and it is mainly used for the screening of chronic granuloma and bacterial system infection. Inspection process (1) Take heparin (100u/ml) anticoagulant 0.1ml into a concave glass slide, add 0.1ml of NBT application solution and 0.1ml of NBT application solution, and mix. In a humid chamber, shake at 37 ° C for 15 min (1 time) and then move to room temperature for 15 min. (2) Take 1 drop of the mixture, push it into thin slices, and dry it. (3) Fix with methanol for 3min, blow dry, add 10.0g / L aqueous solution of sand yellow for 5min (can also be dyed with 50.0g / L methyl green aqueous solution for 15min, or dyed with Giemsa-Rayleigh dye solution), washed with water, Dry. (4) Examination by microscopy, where the cytoplasm of neutrophils contains spotted or blocky dark blue matter, which is NBT-positive cells, the nucleus has different degrees of degeneration, and the cells sometimes become swollen. A total of 100 to 200 neutrophils were counted, and the percentage of NBT positive cells was counted. Not suitable for the crowd There is no inappropriate crowd. Adverse reactions and risks It is a safe check and is harmless to the body.