Considerations in Medical Laboratory Work

1, syphilis primary screening test, in the presence of the former band phenomenon when doing dilution must be replaced when the tip 

2, electrolyte determination, if the blood potassium is very high, but calcium is very low or even negative, to check whether the specimen is anticoagulant blood, possibly EDTA-k2 anticoagulant blood, some nurses draw the wrong blood will be routine blood poured into the biochemical tube.

3, individual women in the menstrual period hormone levels rise, resulting in a false weak positive urine pregnancy test.

4, urine microscopy process, there are small piles of crystals can not be identified as phosphate or urate, you can refer to the urine PH, the former is generally alkaline latter is generally acidic

5, antacid staining is not necessarily positive for Mycobacterium tuberculosis, such as Mycobacterium leprae can also be positive!

6, gram-negative diplococcus is not necessarily gonococcus

7, liver function test, if AST, ALT is very low, about only a few units, the instrument does not happen to automatically dilute, consider the substrate depletion

8, first do the ultrasound and then leave urine for pregnancy test, easy to appear early false negative. The patient is advised that it is best to check the morning urine, urine pregnancy first, and then do ultrasound

9, platelet hypotension in routine blood, pay attention to the histogram.

10, platelet pseudo-hypoglycemia, repeat the test, smear staining, manual counting, and reselect anticoagulant.

11, hemoglobin and red blood cell count generally have a general ratio, if they do not match the difference is large, see if the other three indicators match, the average red blood cell pressure volume (MCV), the average red blood cell hemoglobin content (MCH), the average red blood cell hemoglobin concentration (MCHC)

12, Platelets can also be falsely increased, encountering small red blood cell interference, or red blood cell debris.

13, Urine test strips are prone to false positive nitrites due to moisture.

14, Blood amylase is elevated and blood calcium is decreased.

The action of lipase that enters the peritoneal cavity in pancreatitis causes the fatty tissue on the greater omentum and peritoneum to be digested and decomposed into glycerol and fatty acids, the latter combined with calcium as insoluble calcium fatty acids, and thus serum calcium decreases, such as serum calcium <1.98 mmol/L (8 mg%), suggesting a serious condition and poor prognosis

15, biochemical tests inexplicably cause GGT, or ALP increased a lot, alert tumor metastasis

16, heavy hepatitis in the late stage can appear enzyme bile separation phenomenon

17, Albumin lower than 30g/L, easy to appear ascites

18, HCG can also appear false positive in tumor patients

19, Hepatitis B surface antigen positive, need to consider many false positive may. In order to grasp more accurately, it is better to check hepatitis B two to half, or do neutralization and confirmatory test.

20, vulva disinfection has a great impact on the urine culture, too much disinfectant and mixed into the urine specimen, inhibiting the growth of bacteria, false negative results

21, CA125 is secreted in the abdominal mesothelium under the stimulation of elevated secretion, which can indicate the appearance of effusion, but not the presence of tumor

22, the quality control of indoor quality control products, which affects the quality of the experiment, it is recommended not to freeze and dissolve repeatedly, preferably in small quantities, once used

23, routine blood tests, especially when collecting finger blood, should be stabilized in the anticoagulation tube for about 2 minutes to make the anticoagulation adequate before testing with the instrument, otherwise it is easy to appear monocyte pseudo-elevation.

24, the detection of TB / DB specimens to avoid direct bright light, do not put in the light for a long time

25, ferrous zine method to measure ferric ions, heparin can cause a false increase, if heparin anticoagulation or draw blood in the wrong order will lead to increased ferric ion results

26, HCV antibody test, different manufacturers kits test inconsistent, the possibility of false positives is very high, always pay attention to