Khushnaseeb Ibrahim ( PMRC Research Centre, Jinnah Postgraduate Medical Centre, Karachi. )
Sarwar Jehan Zuberi ( PMRC Research Centre, Jinnah Postgraduate Medical Centre, Karachi. )
Syed Naznil Husnain ( Department of Biochemistry, University of Karachi, Karachi. )
Serum proteins, albumin and globulin in 456 (274 males and 182 females) subjects were within the normal range and showed unifornt distribution. Mean protein levels were low in infants under 0—1 year of age. No significant change was noted with age and sex in other groups. These values were considered to be normal for our population as all protein values fell within 2.5 and 97.5 percentile (95% of the total population) irrespective of age and sex except babies under 0—1 year. The average intake of protein/kg body weight was almost upto the recommended allowances(JPMA 39: 12, 1989).
Serum protein levels in normals vary from 63—8 g% and albumin 4—6 g%1-4. This study repbrts levels of serum proteins, albumin, globulins and albumin/globulin ratios in healthy subjects and their relationship with age, sex and protein intake.
SUBJECTS AND METHOD
One thousand and thirty-six (526 males and 510 females) healthy subjects were selected from the hospital staff, well baby clinics, MCH Centres, primary and secondary schools, colleges and various organizations according to percentage distribution of age and sex in the Karachi population (Census, 1972). Information regarding age, sex, general physical health, dietary history, height and weight were recorded on a preceded proforma. Total serum proteins, albumin and globulin were estimated in 456 (274 males and 182 females) subjects. Dietary intake was recorded according to food consumption of an individual for a week (ICNND-19665). The nutrient intake was calculated from Pellet’s food consumption tables6. Total serum proteins were determined by Biuret7 and albumin by Albustrate kit methods8. Mean, standard deviation, standard error of the mean were calculated. The significance of difference between mean was determined by applying "t" test. The reference ranges for serum proteins, albumin and globulins were calculated using parametric method, mean ±2 standard deviations.
One thousand and thirty-six divided in 11 groups according to of protein intake. 9 The mean age, and animal protein intake (except babies) and proteins/kg body summarised in Tables I and II.
The average protein intake varied from 30-68 gm in males and 29-59.8gm in females. Maximum animal protein intake was in group I in males and group 11 in females. Mean values of serum protein in various age groups in males and females showed uniform distribution. Total serum proteins ranged from 6.4-8.0 G% in males and 6.5-7.8 G% in females. Serum albumin levels varied from 3.6-5.2 g% and 3.6-4.9 g% and globulin levels from 2.7-3.1 g% and 2.5-3.2 g% in males and females, respectively. Slightly lower values for albumin and globulin were observed in infants below 1 year of age. No statistical differences were observed in total protein, albumin and globulin levels in both sexes in various age groups. The average albumin/ globulin ratio ranged from 1.3-2.0 in males and 1.2-1.8 in females. Mean ± 2 S for total protein in all groups except babies from 0-1 years was 7.6g% (5.9 - 93) in males and 73 g% (5.8-8.8) in females and for albumin, 4.8(3.4-6.2) in males and 4.6 (3.3-5.9) in females.
Mean values of serum protein, albumin and globulin are within the range of other reported series in this country and elsewhere1-4,10-12. Mean protein levels were also low in the babies under 1 year of age. 13 No significant change was noted with age and sex in other groups (Table III, IV).
Serum protein intake rather than age higher levels of proteins comparatively higher intake of total proteins and animal proteins (Table I & II). The mean A/G ratio was within normal range in all age groups in both sexes (Table III & IV). A/G ratio is reliable only when it is done in serum. Ratio is incorrect in plasma because of fibrinogen. Protein values reach the normal levels observed in this series and other series after the age of 1 year3,4,14. All proteins value were within 2.5 and 97.5 percentile (95% of the total popqlation) irrespective of age and sex in an individual except babies under 1 year (Table III & IV). These values were considered to be normal as their total protein intake/ nearly upto the recommended intake9,15-17. In addition to providing baseline data on healthy individuals of various ages and sex, this study also furnishes the necessary foundation for the interpretations and findings in various disease states in our population.
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6. Pallet, P.L. and Shadarevian, S. Food composition tables for use in the Middle East Beirut, 1970.
7. Kingsley, G.R. The direct biuret method for the determination of serum proteins as applied to photoelectric and visual colorimetry. J. Lab. Clin. Med., 1942; 27:840.
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13. Oberman, LW., Gregory, K.O., Burke, F.G., Ross, S. and Rice, E.C. Electrophoretic analysis of serum proteins in infants and children I. Normal values from birth to adolescence. N. Engl. 3. Med., 1956; 255 :743.
14. Metcoff, J. and Stare, F .3. The physiologic and clinical significance of plasma proteins and protein metabolites. N. Engl. J. Med., 1947; 236;26.
15. Hegsted, D.M., Tsongas, A.G., Abbott, DJ3. and Stare, F.J. Protein requirements of adults. J. Lab. Clin. Med., 1946;31: 261.
16. National Health Laboratory Guide notes on nutrition for the nutrition training programme in Pakistan. Islamabad, Nutr. Div. NHL, 1972, p.115.
17. Khan, MA. and Khan,M.A. National standard of growth for infants and young children and Recommended Dietary Allowances for Pakistani population, Planning and Development Div. Govt. of Pakistan 1980, p. 105.