Question

Normal blood calcium level in an adult is

• A. 5 mg/dl
• B. 8.5 - 10.5 mg/dl
• C. 15.5 - 20 mg/dl
• D. 20 - 30mg/dl

Answer 1

The correct option is B 8.5 - 10.5 mg/dl

Calcium concentration is characterized by a high physiological variation, depending on age, sex, physiological state (eg, pregnancy). Therefore, separate reference intervals have been established according to the age and sex of the individual being tested. Total calcium reference ranges in males are as follows: age 1-14 years: 9.6 - 10.6 mg/dL; age 15-16 years: 9.5 - 10.5 mg/dL; age 17-18 years: 9.5-10.4 mg/dL; age 19-21 years: 9.3-10.3 mg/dL; age 22 years and older: 8.9-10.1 mg/dL. Total calcium reference ranges in females are as follows: age 1-11 years: 9.6-10.6 mg/dL; age 12-14 years: 9.5-10.4 mg/dL; age 15-18 years: 9.1-10.3 mg/dL; age 19 years and older: 8.9-10.1 mg/dL.