Hepatic Enzyme's Reference Intervals and Their Modulating Factors in Western Indian Population

Reference intervals for common clinical chemistry parameters in healthy adults of Northeast Ethiopia

BACKGROUND

Clinical chemistry reference intervals are important tools for health evaluation, diagnosis, prognosis and monitoring adverse events. Currently used reference intervals in most African countries including Ethiopia are mainly derived from Western populations, despite studies reporting differences that could lead to incorrect clinical decisions. The aim of this study was to establish reference intervals for commonly used clinical chemistry parameters for healthy adults in Northeast Ethiopia.

METHODS

A community based cross-sectional study was conducted among 328 apparently healthy adults between the ages of 18 and 57 years. Blood samples were collected for clinical chemistry analysis using Dirui CS-T240 auto-analyzer and serological testing to screen the population. Medians and 95% reference intervals were computed using non-parametric method according to the Clinical and Laboratory Standards Institute guideline. The Mann-Whitney U test was used to compare reference values between males and females.

RESULTS

Reference intervals established were: ALT 11.2-48.0 U/L, AST 16-60 U/L, ALP 53-342.3 U/L, total protein 5.4-8.9 mg/dL, total bilirubin 0.1-1.23 mg/dL, glucose 65-125 mg/dL, total cholesterol 69-213 mg/dL, triglycerides 46-207 mg/dL, creatinine 0.3-1.2 mg/dL and urea 9.5-46.3 mg/dL. Significant sex-differences were observed for ALT, AST, ALP, total cholesterol, triglycerides, creatinine and urea. We found that the established reference intervals substantially differ from the reference ranges currently in use. Up to 43.1% of apparently healthy adults are considered as having abnormal test values on the bases of the currently in use reference ranges. If the reference values from the United States based intervals were applied to the study population, 81.8% would have been classified as having abnormal laboratory test results.

CONCLUSIONS

Local population-specific reference intervals were established for commonly used clinical chemistry parameters in adult population of Northeast Ethiopia. Although further study is needed, these reference intervals may have the potential to facility the decision-making process based on laboratory test results in this population.

Risk of mortality and level of serum alanine aminotransferase among community-dwelling elderly in Israel

BACKGROUND

Serum alanine aminotransferase (ALT) levels below and above the reference range have been found to serve as a marker of liver injury and to predict all-cause mortality. The need to adjust the reference range by age, sex, or other parameters remains unclear. The current reference range of serum ALT in Israel is 0-34 IU/l for women and 0-45 IU/l for men. We aimed to test the applicability of the current reference range values of ALT in specific people - the elderly population.

METHODS

A retrospective design was used. The study population consisted of community-dwelling individuals aged at least 65 years who were tested for serum ALT in 2002 at a large health management organization and followed until the end of December 2012. Data were collected on demographics, laboratory tests, comorbidities, and mortality.

RESULTS

A total of 49 634 participants (59% women, mean age 83.2±6.3 years) were included. ALT levels between 16 and 25 IU/l were associated with the lowest mortality (hazard ratio=1), and values of less than 16 IU/l and more than 25 IU/l (unadjusted) were associated with higher mortality risk, yielding a U-shaped pattern.Highest mortality rates were also revealed at serum ALT levels more than 56 IU/l and less than 10 IU/l. A significant association of higher mortality risk was noted with lower mean values of hemoglobin, albumin, and total cholesterol, both for patients with lower serum ALT levels (<10 IU/l) and patients with higher serum levels (>56 IU/l).

CONCLUSION

Very low and very high levels of serum ALT within the current reference range are associated with an increased risk of death in community-dwelling individuals of at least 65 years old.

Estimation of Upper Limit of Normal for Serum Alanine Transaminase in Healthy South Indian Population

Alanine aminotransferase (ALT) is the most common and cost effective screening test for asymptomatic liver disease. There is paucity of data on normal ALT among healthy individuals in India. An observational cross sectional study was conducted from January to July 2013 to estimate the upper limit of normal for ALT in healthy south Indian population. Adults undergoing voluntary or pre-employment health screening were included. Those with current and past alcoholism or smoking, acute illness or hospitalization during preceding 12 months, non-steroidal anti-inflammatory or over the counter medication use within a month, current or past intake of herbal medications, any chronic medical illness, abnormal body mass index (BMI), fatty liver in ultrasound, abnormality in haemoglobin, platelet count, blood sugar, creatinine, lipid profile and thyroid function test and positive serology (Hepatitis B, C or HIV) were excluded. A total of 2600 subjects were screened. 344 were included for analysis. Mean age was 35 years in men and 34.83 years in women, with a mean BMI of 22.2 kg/m² in men and 21.8 kg/m² in women. The mean ALT in men and women were 21.87 ± 2.9 (97.5th percentile 28 U/L) and 19.35 ± 3.3 (97.5th percentile 24 U/L) respectively. In conclusion, mean and upper limit of ALT (97.5th percentile) in south Indian men was 21.87 and 28 IU/L and women were 19.35 and 24 IU/L respectively. There is a need to re-consider ALT levels in our population for better detection of individuals at risk for liver disease.