Prevalence of asymptomatic urinary abnormalities among students of a university – A cross sectional study

 

Hemanth Kumar S R^1*, Mallikarjan S Khanpet², Apoorva E Patel³

 

 

Abstract              Background and Objectives: An abnormal urinary testy may be the earliest warning of a significant renal pathology. With the aid of routine Dipstick examinations, early symptoms of diseases of the kidneys and the urinary tract (pyuria, hematuria and proteinuria) can be identified. The present study was undertaken to assess the prevalence of asymptomatic urinary abnormalities, which will help to prevent the progression of the same into Chronic Kidney Disease or to postpone the need for renal replacement and other abnormalities of the urinary system. Methodology: The present one year cross sectional study was conducted in the Department of Medicine, Jawaharlal Nehru Medical College, Belgaum. A total of 849 undergraduate Medical and Dental students studying at Jawaharlal Nehru Medical College, Belgaum and KLES V. K Institute of Dental Sciences, Belgaum during January 2016 to December 2016 were included. Urine samples were collected in sterile wide mouthed containers and tested using Dipsticks. The color change on the Dipstick due to chemical reactions was compared to standard chart and results were interpreted and the abnormalities were analyzed. Results: Of the 849 students, 320(37.69%) were males and 529(62.31%) were females. Majority of the students were aged around 20 years old. A total of 79 (9.31%) students had asymptomatic urinary abnormalities. 51(6.01%) students had proteinuria, 18(2.12%) had hematuria and Nitrituria was seen in 10(1.18%) female students. Proteinuria (6.42% v/s 5.31%) and hematuria (2.27% v/s 1.88%) were more common in females. Interpretation and Conclusion: Overall, in the present study there was a significantly higher prevalence of asymptomatic urinary abnormalities among apparently healthy young adults. The students who had urinary abnormalities need further evaluation in detail.

Key Words: Asymptomatic urinary abnormalities, Proteinuria, Hematuria, Pyuria, Nitrituria.

 

INTRODUCTION

Abnormalities detected in routine urine analysis in patients who have no symptoms of renal or urologic disease such as glycosuria, pyuria, hematuria and proteinuria are a common finding in clinical practice. Renal diseases are often accidently discovered during routine urine analysis in asymptomatic healthy individuals.¹ With the aid of routine Dipstick examinations early symptoms of diseases of the kidneys and the urinary tract (pyuria, hematuria and proteinuria) can be identified. 2 An abnormal urinary test maybe the earliest warning of a significant renal pathology.3,4Proteinuria is a strong independent predictor and risk factor of End Stage Renal Disease (ESRD).⁵ Although transient proteinuria typically is a benign condition, persistent proteinuria requires further workup.⁶ Micro hematuria has a range of causes- from benign to life threatening. Glomerular, renal and urologic causes of micro hematuria often can be differentiated by other elements of the urine analysis.⁶ In a study⁷, asymptomatic hematuria among young adults was found to be an independent potential risk for development of future ESRD due to glomerular etiology. Various other studies^8,9,10 have also shown that asymptomatic hematuria is associated with significant risk of ESRD and bladder tumors. Many renal diseases are found to begin at a very young age, early detection of urinary abnormality is useful in selecting patients who require long term surveillance. Almost 80% of patients who come with CKD cannot afford renal replacement therapy. Mass urinary screening helps to determine the prevalence of renal diseases and to improve the outcome in the population. At present, there are not much studies in India to show the prevalence of Asymptomatic urinary abnormalities in healthy young adults. Hence, the present study was undertaken to assess the prevalence of asymptomatic urinary abnormalities which will help to prevent progression into CKD or to postpone the need for renal replacement and other abnormalities of the urinary system. This study addresses this issue with an attempt to characterize these abnormalities in young individuals.

 

MATERIALS AND METHODS

The present study was a cross sectional study, conducted by the Department of General Medicine, Jawaharlal Nehru Medical College, Belgaum, Karnatakaon 849 Undergraduate Medical and Dental students studying at KLE University, Belgaum during the period of January 2016 to December 2016.

Sample size: All the students from the two courses (Undergraduate Medical and Dental) were included in the study. A total of 933 students were considered for the study out of which 84 declined to participate in the study, so a total of 849 students were included in the study.

Selection Criteria: Subjects were selected based on a questionnaire to rule out hypertension, diabetes mellitus, renal disease, urinary tract infection, febrile illness (during the past two weeks) and drug intake. Female subjects who were menstruating or pregnant were not considered for the study. Thorough physical examinations including blood pressure recording and systemic examination were carried out to exclude diseases which can cause urinary abnormalities.

Method of collection of data: The study was approved by the Institutional Ethics Committee of Jawaharlal Nehru Medical College, Belgaum. The selected individuals were briefed about the nature of the study and a written informed consent was obtained. Demographic data like gender and age were collected and recorded on predesigned and pretested proforma. A thorough clinical examination was conducted and the findings were also recorded. Urine samples were collected in sterile wide mouthed containers. An early morning mid stream clean catch urine samples were collected and analysed. Urine examination included physical examination (Colour and appearance) and dipstick analysis to look for proteins, blood, nitrites and glucose. The urine examination was carried out with ready to use dip sticks URS-9 of TECO Diagnostics. Readings were taken between one to two minutes. Any colour change after two minutes were not considered. The colour change on the dip stick due to chemical reaction was compared to standard chart and results were interpreted and the abnormalities were analysed as shown in Table 1below.

 

Table 1: Comparative Colorimetric Chart for Grading Urinary Abnormalities by Dipstick Method:

Components	Colour	Grading	Semi quantitative result
Protein	Yellow	Negative	-
	Light Green	Trace	< 30 mg/dL
	Green	1+	30 mg/dL
	Dark Green	2+	100 mg/dL
	Blue Green	3+	300 mg/dL
	Darkish blue green	4+	> 2000 mg/dL
Blood	Orange	Negative	-
	Orange background with greenish spots	Non hemolysed trace	10 cells/μL
	Uniform yellow green	Hemolysed trace	10 cells/μL
	Light green	1+	25 cells/μL
	Dark green	2+	80 cells/μL
	Dark Blue	3+	200 cells/μL
Nitrite	White	Negative	-
	Any grade to pink	Positive
Glucose	Light green	Negative
	Blue green	Trace	100 mg/dL
	Greenish brown	1+	250 mg/dL
	Brown	2+	500 mg/dL
	Dark brown	3+	1000 mg/dL

Source: URS 9, TECO Diagnostics, California, USA

Statistical Analysis: Data obtained was tabulated on Microsoft excel spread sheet and analysed. The results were expressed as rates, ratios and percentages.

 

RESULTS

Out of 849 study subjects, 538 (63.37%) were Medical undergraduate students and remaining 311 (36.63%) were Dental undergraduate students. Of the total 849 study subjects, 320 (37.69%) were males students and remaining 529 (62.31%) were females students. All the students were aged between 18-22 years of age, with the majority being 20 years old (23%). A total of 79 students (9.31%) had Asymptomatic Urinary Abnormalities, of which 51 (6.01%) students had proteinuria, 18 (2.12%) had hematuria and Nitrituria was seen in 10 (1.18%) female students. Proteinuria (6.42% v/s 5.31%) and hematuria (2.27% v/s 1.88%) were more common in females. Asymptomatic glycosuria was not found in any of the study subjects. Those who had urinary abnormalities had only one urinary abnormality and no one had more than one urinary abnormality.

 

DISCUSSION

Routine urinalysis of asymptomatic patients has been shown to detect a variety of urinary abnormalities. A number of studies have demonstrated the usefulness of dipstick in screening asymptomatic patients.^11,12 Urine dipstick is sensitive for detection of proteins, blood, nitrites and glucose.^13,14 Carl et al screened 2100 healthy adults by dipstick method and found that 10% adults had at least one urine abnormality detected.15 Because of its simplicity, a general practitioner or a nurse can carry it out. This would reduce the workload on the laboratories. In the present study, Prevalence of asymptomatic urinary abnormalities was 9.31%. This is similar to a study conducted in Egypt¹⁶, where in the prevalence of asymptomatic urinary abnormalities was around 13.8% on second screening. Also in our study, the prevalence of asymptomatic urinary abnormalities was more in females (10.58%) as compared to males (7.18%). Hanif R et al¹⁷ reported an overall prevalence of urinary abnormalities of 19.3% among patients attending rural health centers in Pakistan. Also in the study, females (26.25%) had a greater prevalence of asymptomatic urinary abnormalities compared to males (14.66%) similar to our study. In the present study, prevalence of asymptomatic proteinuria was 6.01%. In comparison to our study, Singh NP et al18 reported 2.25% prevalence of proteinuria among North Indian population of the subjects screened with a mean age of 54 years. Another study19 done by Ahmed et al on south Indian population showed a prevalence of 4.3%, which is similar to our findings. A long term follow-up study20 of young students who were diagnosed with proteinuria at the time of entering the university showed a higher mortality (43%) due to renal disease.In the present study, majority of students who had asymptomatic proteinuria (4.38%) were having mild proteinuria (1+). Since these milder forms of proteinuria tend to be neglected when found on routine examination, these patients are predisposed to develop complications and early progression into ESRD. Therefore asymptomatic proteinuria warrants further work up and intervention to reduce the incidence of ESRD. In the present study, prevalence of asymptomatic hematuria was 2.12%. This is in contrast with a study conducted in Egypt11 wherein Hematuria was the most common abnormality found, with the prevalence of 9.8% among all adolescents.Also in our study, Females had higher prevalence rate (2.27%) of asymptomatic hematuria compared to males (1.88%). In a study by Prakash J et al²¹, prevalence of microscopic hematuria was reported as 3% among 315 elderly Indians screened (age >60 years). In a study by Mohr DN8, asymptomatic hematuria was reported to be 12.37% among 23,204 Minnesota residents screened (58% men, women; men aged >35 and women >55). This obvious difference may be because of the higher age of the population screened as elderly more predisposed to glomerular and urological diseases. The differences in the prevalence of hematuria in various studies mentioned above may be because of screening heterogeneous population of different age group. Uncomplicated urinary tract infections diagnosed by positive leukocyte esterase and nitrite tests can be treated without culture. In the present study, asymptomatic nitrituria which indicates asymptomatic Urinary tract infection was seen only in female students with a prevalence of 1.18%. In various studies,22,23 prevalence of asymptomatic Urinary tract infection have been reported as 5% in young females and less than 0.01% in young males. None of the students in this study had asymptomatic glycosuria. In contrast to our study, Hanif R et al¹⁷ reported a prevalence of 2% glycosuria among patients attending rural health centers in Pakistan. In the study, the prevalence of glycosuria was more in patients aged above 40 years. This may be due to the reason that Diabetes Mellitus was not ruled out in the population screened.

 

CONCLUSION

ESRD engenders an extremely poor quality of life and shortens life expectancy. Therefore, diagnosis of these abnormalities early can possibly identify individuals at risk, thereby dictating options to mandate a therapeutic protocol.In the present study, the prevalence of asymptomatic proteinuria and hematuria was significantly higher compared to previous studies. This significantly higher prevalence of asymptomatic proteinuria and hematuria needs further follow-up and evaluation of those having these abnormalities. This study warrants the need of a national screening program for early detection of urinary abnormalities.

 

REFERENCES

1. Ahmed Z, Lee J. Asymptomatic urinary abnormalities. Hematuria and proteinuria. Med clin North Am 1997;81:641-52
2. Longo DL, Kasper DL, Jameson JL, Fauci AS, Hauser Sl et al. Harrison’s Principles of Internal Medicine.18th Ed. New Delhi: McGraw Hill Medical Publishing Division, 2011
3. Abitbol C, Zilleruelo G, Freundlich M. Quantitation of proteinuria with urine protein/creatinine ratios and random testing with dipsticks in children. J Pediatr 1990; 116: 243-7.
4. Bard RH: The significance of asymptomatic hematuria in women and its economic implications: A ten-year study. Arch Intern Med 1988; 148: 2629-32.
5. Iseki K, Ikemiya Y, Iseki C, Takishitas S. Proteinuria and Risk of developing end stage renal disease. Kidney Intl 2003; 63: 1468-74.
6. Simerville JA, Maxted WC, Pahira JJ. Urinalysis: A Comprehensive Review. Am Fam Physician 2005; 71(6): 1153-62.
7. Vivante A, Afek A, Frenkel-Nir Y, Tzur D, Farfel A, Golan E, et al. Persistent asymptomatic isolated microscopic hematuria in Israeli adolescents and young adults and risk of end – stage renal disease. JAMA 2011; 306(7): 729-36.
8. Mohr DN, Offord KP, Owen RA, Melton LJ 3d. Asymptomatic micro-hematuria and urologic disease. A population-based study. JAMA 1986; 256: 224–9.
9. Mohr DN, Offord KP, Melton LJ 3d. Isolated asymptomatic microhematuria: a cross-sectional analysis of test-positive and test-negative patients. J Gen Intern Med. 1987; 2: 318–24.
10. Messing EM, Young TB, Hunt VB, Emoto SE, Wehbie JM. The significance of asymptomatic microhematuria in men 50 or more years old: findings of a home screening study using urinary dipsticks. J Urol 1987; 137: 919–22.
11. Waugh JJ, Clark TJ, Divakaran TG, Khan KS, Kilby MD. Accuracy of urinalysis dipstick techniques in predicting significant proteinuria in pregnancy. ObstetGynecol 2004; 103: 769-77.
12. Molvneux EM, Robson WJ. A dipstick test for urinary tract infections. J AccidEmerg Med 1995; 12: 191-3.
13. Lum G. How effective are screening tests for microalbuminuria in random urine specimens? Ann Clin lab Sci 2000; 30: 406-11.
14. Misdraji J, Nguyen PL. Urinalysis. When and when not to order. Postgrad Med 1996; 100: 173-6.
15. Carl RS, Silverberg DS, Kaminsky R, Aviram A. Routine urinalysis (dipstick) findings in mass screening of health adults. Clin chem. 1987; 33: 2106-8.
16. Fouad M, Boraie M.Prevalence of Asymptomatic Urinary Abnormalities Among Adolescents.Saudi J Kidney Dis Transpl 2016;27(3):500-506.
17. Hanif R, Ally SH, Jalal-ud-din, Khan K. Effectiveness of routine urine analysis of patients attending rural health centres in Abbottabad. J Ayub Med Coll Abbottabad 2006; 18 (3): 63-64.
18. Singh NP, Ingle GK, Saini VK, Jami A, Beniwal P, Lal M and Meena GS. Prevalence of low glomerular filtration rate, proteinuria and associated risk factors in North India using Cockcroft-Gault and Modification of Diet in Renal Disease equation: an observational, cross-sectional study. BMC Nephrology 2009; 10: 4.
19. Ahmed I, John GT, Kirubakaran MG. Prevalence of proteinuria in rural adult population in Tamil Nadu. Ind J Med Res 2006; 124: 185-8.
20. Levitt JI: The prognostic significance of proteinuria in young college students. Ann Intern Med 1967; 66(4): 685-96.
21. Prakash J, Singh AK, Saxena RK, Usha. Glomerular diseases in the elderly in India. International Urology and Nephrology 2003; 35: 283–8.
22. Vorland LH, Carlson K, Aalen O. An epidemiological survey of urinary tract infections among outpatients in Northern Norway. Scand J Infect Dis 1985; 17: 277-83.
23. Valkenburg HA. Epidemiology of urinary tract infections. Urol 1987; 13 (Suppl 1): 5-8.