A Screening Tool for Renal Trauma? Using Urinalysis for Detecting Post-Game Haematuria in Elite Rugby Union. A Screening Tool for Renal Trauma? Claire Strickland(1), Dr. Jonathon Greenwell(2), Dr Daniella Strauss(1) (1) University of Leeds (2) Leeds Rugby Introduction Several studies have analysed haematuria in athletes post-exercise in both contact and non-contact sports. There is debate whether the main cause is physiological or due to trauma (1, 3, 6). Post-game haematuria in rugby union has not been studied before. As a contact sport associated with high velocity impacts, it has been described, along with road traffic accidents, as one of the most common causes of serious abdominal injuries caused by blunt trauma (7), the most common of these being genitourinary. Other possible causes of post-game haematuria in rugby union include indirect bladder and kidney trauma (2), physiological changes in renal function during exercise (4), underlying renal pathology and “athletic pseudonephritis”, a benign exercise-induced haematuria and proteinurea in which all abnormalities return to normal soon after exercise has finished (5).   Aim To determine the incidence of post-game haematuria in elite rugby union, its potential cause and consequently if dipstick urinalysis is a useful screening tool post-game to detect serious renal trauma. Results and Discussion All baseline urinalyses were negative. There was a significant difference between the overall incidence of haematuria post-training, 7.7% and post-game, 24.4%. (t(144) = 3.007, p = 0.003). Suggesting the majority of post-game haematuria was related to a match-play factor, possibly trauma from contacts. Post-training haematuria did occur therefore some haematuria had to be related to something other than trauma, possibly physiological changes during exercise.   Table 1. Percentage incidence of post-game haematuria per match and overall incidence over all the matches. Match 1 Match 2 Match 3 Match 4 Match 5 Overall Incidence of post-game haematuria (%) 21 28 24 24.4 Table 2. Percentage incidence of post-training haematuria per training session and overall incidence of all the sessions. Training 1 Training 2 Training 3 Training 4 Overall Incidence of post-training haematuria (%) 6 10 5 7.7 All post-game and post-training haematuria was microscopic. There was no frank haematuria. Trace was the most common level of haematuria both post-game and post-training. Moderate levels of haematuria were only found post-game. Large levels of haematuria were not found (Figure 2).   All samples were negative 24-48 hours post-game. There was no delayed onset haematuria. Microscopic haematuria that clears after 24-48 hours can be classed as “athletic pseudonephritis”. There was no correlation between levels of post-game haematuria and duration played (r = 0.036, n = 65, p = 0.777) or number of contacts (r = 0.058, n = 65, p= 0.645). Possibly because it was not the number of contacts that caused trauma, but the force and area of the contact. Methods 30 male, elite rugby union players participated in the study. We collected baseline urine samples at the start of the season, during a rest phase, and then data was collected after 5 games during the season. Samples were taken immediately post game, and then again at 24-48 hrs. Control samples were also taken after 4 non-contact training sessions. There were five measurements for haematuria: negative, trace  10 Ery/l, small  25 Ery/l, moderate  80 Ery/l, and large  200+ Ery/l (Figure 1). Subjects with frank haematuria, no resolution, persistent abnormalities or history of pain were investigated further. Incidence of post-game and post-training haematuria were calculated and compared using an independent samples t test. Duration played and total number of contacts for each player per game were recorded and analysed using SportsCode video analysis software. This was compared with levels of post-game haematuria using Pearson product-moment correlation coefficients. Introduction Figure 2. The occurrence of each measurement of haematuria as a percentage of total number of samples post-game and post-training. Conclusion Post-game haematuria occurs in rugby union and appears to be related to a match-play factor, possibly direct renal trauma from contacts and/or a physiological change in renal function. All post-game haematuria was microscopic and cleared after 24-48 hours, therefore it can be classed as “athletic pseudonephritis”; no lasting damage is indicated and there seems no need to restrict activity. Frank haematuria did not occur but may indicate injury or underlying pathology and requires specialist urological investigation. This study suggests that post-game urinalysis for haematuria would not be a useful screening tool to detect serious renal trauma in rugby union. References 1. Alyea E P, and Parish H H. Renal response to exercise-urinary findings. Journal of the American Medical Association. 1958;167(7):807-13. 2. Blacklock N J. Bladder trauma in the long-distance runner. American Journal of Sports Medicine. 1979;7(4):239-41. 3. Boone AW, Haltiwanger E, and Chambers RL. Football hematuria. Journal of the American Medical Association. 1955;158(17):1516-7. 4. Castenfors J. Renal function during prolonged exercise. Annals of the New York Academy of Sciences. 1977;301(1):151-9. 5. Gardner KD. "Athletic pseudonephritis"-alteration of urine sediment by athletic competition. Journal of the American Medical Association. 1956;161(17):1613-7. 6. Kleiman AH. Hematuria in boxers. Journal of the American Medical Association. 1958;168(12):1633-40. 7. Mitchell JP. Injuries to the upper urinary tract. Postgraduate Medical Journal. 1967;43(500):415-8 Figure 1. Photograph of the DIRUI A10 reagent strips colour chart, showing 5 measurements for blood.