ABSTRACT
BACKGROUND: It has been well known that normal leukocyte counts in blood can vary depending on age, gender, other environmental factors and ethnic differe nces. However, the normal white blood cell counts in Koreans has not been settled yet. Over past several years, a large number of patients were referred to the Hematology Clinic of Asan Medical Center (AMC) for evaluation of "leukopenia", and most of them were found to have no medical problems other than leukocyte counts less than 4,000/mm3. We performed this study on persons who visited Health Screening Center to analysis of leukopenic patients and also to establish the normal value of white blood cell counts in Korean. METHOD: We studied 31,307 persons (19,540 men, 11,767 women, aged 15-90), who visited to Health Screening Center of AMC during the period from January through December 1995. We have carried out retrospec tive analysis of complete medical record of 2,406 patients (838 men, 1,568 women, aged 20-81) who were found to have leukocyte counts less than 4,000/ mm3. And we tried to establish the normal values of leukocyte counts and differential counts of 24,079 adults (15,807 men, 8,272 women, aged 19-90), who were assessed to be healthy at Health Screening Center of AMC. RESULTS: 1) Leukopenia (WBC<4,000/mm3) were found in 2,406 subjects (7.7%) among 31,307 persons screened. 2) Among them, 77 subjects (3%) had medical illness; 39 of them had chronic B or C viral hepatitis, 24 of them had iron deficiency anemia, and other diseases were de tected in remaining 14 patients. But other hematologic dis eases or significant infectious diseases were not detected. Follow-up study of them has indicated no increased incidence of infection or other hematologic diseases. 3) The total white blood cell counts of 24,097 healthy Korean adults were 3,640-9,870/mm3 (5,900/ mm3) in men, and 3,270-8,400/mm3 (5,264/mm3) in women. Neutrophil counts ranged 1,288-6,866/mm3 (3,098/mm3) in men, and 1,180-5,985/mm3 (2,816/mm3) in women. Leukocyte counts were significantly lower in female, but no significant variation was found among age groups. CONCLUSION: Normal range of leukocyte counts and neutrophil counts of healthy Korean adults were lower than those of white populations. Thus, a new normal values of leukocyte and neutrophil counts should be established in Koreans. And many persons with leuko cyte counts less than 4,000/mm3 who are otherwise he althy could be normal.