Effects of biological variations on platelet count in healthy subjects in China.

The effects of biological variations on platelet counts were investigated in 694 healthy subjects aged 18 to 60 years living in three cities including Chengdu (Sichuan Province), Suzhou (Jiangsu Province) and Harbin (Heilongjang Province) in China. Platelet counts in healthy subjects were significantly lower in Chengdu (52-202 x 10(9)/L) and Suzhou (60-259 x 10(9)/L) than in Harbin (154-348 x 10(9)/L) (p <0.0001), but the mean platelet volume (MPV) determined concurrently was negatively correlated with platelet count, the MPV values were significantly higher in Chengdu (11.8-15.6 fl) and Suzhou (10.9-15.8 fl) than in Harbin (9.5 approximately 12.9 fl) (p < 0.0001). Platelet counts were significantly higher in summer (73-289 x 10(9)/L) than in winter (52-202 x 10(9)/L) (p <0.0001), but the MPV values were lower in summer (11.2-14.7 fl) than in winter (11.8-15.6 fl) (p <0.05) in Chengdu. Platelet associated immunoglobulin (PA-IgG) in Chengdu was revealed to be significantly higher in the low platelet count group (<150 x 10(9)/L, 13.5 +/- 7.1 ng/10(7) PLT) than in the normal platelet count group (> or =150 x 10(9)/L, 8.3 +/- 2.7 ng/10(7) PLT) (p <0.0001). Similar results were observed in Suzhou for the reticulated platelet ratio, which was significantly higher in the low platelet count group (19.5 +/- 7.1%) than in the normal platelet count group (11.6 +/- 2.7%) (p <0.01). The bleeding time in Chengdu showed a significantly longer time in the low platelet count group (8.6 +/- 2.3 min) than in the normal platelet count group (6.0 +/- 1.2 min)(p <0.01). With regard to the effects of lipids on platelet counts, the HDL values were significantly higher in the normal platelet count group (1.60 +/- 0.76 mmol/L) than the low platelet count group (1.23 +/- 0.31 mmol/L) (p <0.01); but no significant differences in cholesterol and triglycerides values between the normal and low platelet count groups (p >0.05) were recorded. These findings suggest that the platelet counts could be greatly influenced in healthy subjects by biological variations such as geographical, seasonal, and lipid variations.

[Establishing the reference range of venous blood measured by automated haematology analyzer in Chinese adults].

OBJECTIVE: To establish the reference range of venous blood measured by automated hematology analyzer in China. METHODS: Different hematoanalyzers were used to examine the white blood cell (WBC), red blood cell (RBC), hemoglobin (Hb), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular volume (MCV), and hemotocrit (HCT) of venous blood from 1,749 healthy people, 927 males and 822 females, aged 18 - 60, in 14 cities (Harbin, Changchun, Beijing, Tianjin, Lanzhou, Xi'an, Nanjing, Suzhou, Chengdu, Wuhan, Chongqing, Fuzhou, Kunming, and Guangzhou) of China. The examination was completed within the period of one month under strict in-laboratory quality control. RESULTS: The range of WBC was (3.97 - 9.15) x 10(9)/L in males and (3.69 - 9.16) x 10(9)/L in females. The range of RBC was (4.09 - 5.74) x 10(12)/L in males and (3.68 - 5.13) x 10(12)/L in females. The range Hb was 131 - 172 (151) g/L in males and 113 - 151 (129) g/L in females. The range of MCH was 27.8 - 33.8 (30.8) pg in males and 26.9 - 33.3 (30.2) pg in females. The range of MCHC was 263 - 375 (335) g/L in males and 278 - 372 (325) g/L in females. The range of MCV was 83.9 - 99.1 (91.2) fl in males and 82.6 - 99.1 (91.3) fl in females. The range of HCT was 38.0% - 50.8% (44.8%) in males and 33.5% - 45.0% (38.9%) in females. The lower limits of WBC in Lanzhou and Chengdu were lower than those in other cities (P < 0.01). The concentrations of RBC and Hb in Kunming were significantly higher than those in other cities (P < 0.01). There was no significant difference in other parameters among different cities. The WBC, RBC, and Hb in the females were lower than those in the males (P < 0.01). CONCLUSIONS: The reference ranges of different parameters of venous blood of Chinese have been primarily established. There is little discrepancy in those reference range in different district (except for highland). Some of the indices such as WBC, MCH and MCV measured by analyzer are quite different from those measured manually.

Studies on reference intervals for platelet counts in three cities in China and one in Japan.

Hematological parameters including platelet counts, etc. were determined in 1,140 healthy subjects living in four cities: Suzhou (Jiangsu Province), Chengdu (Sichuan Province) and Harbin (Heilongjang Province) in China, and Kobe in Japan. Then, the reference intervals for platelet counts were calculated and compared. The reference interval for platelet count of subjects aged between 18 and 60 years was 60-259 x 10(9)/L in Suzhou and 52-202 x 10(9)L in Chengdu, and subjects with platelet counts of 100 x 10(9)/L or less accounted for about 30% of the subjects examined in these cities. The reference intervals in Harbin and Kobe were within the range of 150-350 x 10(9)/L, and no subject having a platelets count of 100 x 10(9)/L or less was detected. Mean platelet volume (MPV) determined concurrently was negatively correlated with platelet count, and the reference intervals for MPV in Chengdu and Suzhou were higher than those in Harbin and Kobe.