Renal Laceration in a High School Football Player
Randell K. Wexler, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 31 - NO. 2 - FEBRUARY 2021
In Brief: Renal laceration, though uncommon, is a danger for any active person, particularly in collision or contact sports. A traumatic blow to the abdomen or flank can cause kidney damage, and, if left untreated, renal injury may lead to hypertension. Hematuria is often the most obvious sign that alerts clinicians to a renal laceration. The extent of the damage can be evaluated with CT. Conservative treatment of monitoring vital signs is recommended for managing lesser injuries, but intraperitoneal trauma or injury to the renal pedicle may require surgical intervention.
Although the spleen is the most commonly injured abdominal organ in athletes,1 the kidney is the most commonly injured genitourinary organ after a traumatic blow to the abdomen or lower back.2 Contact and collision sports are more likely to produce a renal injury, but any sport in which trauma can affect the abdomen or back is risky. Minor injuries to the kidney, such as subcapsular hematomas, may not be life threatening, but they are not without morbidity. The case of a high school football player who suffered a renal laceration underscores the need for continuing observation of athletes whose injuries initially seem minor and highlights current concepts in the management of blunt renal trauma.
History. Midway through the second quarter of a high school football game, a 17-year-old defensive player came to the sidelines reporting back and flank pain after a pile-up. Initial evaluation showed three small, nonbleeding abrasions on his flank, but no ecchymosis. Palpation produced tenderness over the left lower back and flank. Ice was applied for 10 minutes. The player felt well enough to return to the game, and the repeat exam appeared normal. About 2 minutes before halftime, the player returned to the bench reporting left flank and low-back pain. Ice was reapplied, and we decided to do a gross urine examination and physical exam at halftime.
A few minutes after entering the training room, the athlete was sent to the restroom to produce a urine specimen. About 60 seconds later, we heard him scream upon seeing that the toilet bowl was full of bright red blood. He was promptly brought to the training room, and emergency protocol was activated.
Physical exam. On reexamination, his pulse was 86/min and regular, respirations were 14/min and unlabored, and blood pressure was 154/84 mm Hg. The patient was alert and oriented but in mild distress, and he was splinting on his left side. His head, eyes, ears, nose, and throat exam was unremarkable, his lungs were clear bilaterally, and his heartbeat was rhythmic and without murmur. The patient's abdomen was soft and nontender, his bowel sounds were normal, and he showed no peritoneal signs. Inspection of the left flank revealed three 1-cm X 1-cm nonbleeding abrasions, but no flank swelling, erythema, or ecchymosis. Left flank palpation produced mild tenderness. Repeat vital signs were normal when the paramedics arrived and transported him to the hospital.
Radiology and lab work. In the emergency department, computed tomography (CT) scan of the patient's abdomen revealed a lacerated kidney and a perinephric hematoma (figure 1). He remained hemodynamically stable, and arrangements were made to transfer the patient to a facility having a trauma department. On admission, his test results were as follows: hemoglobin, 10.8 g/dL; hematocrit, 32.4 mL/dL; white blood cell count, 3.7 million/mm3; platelet count, 175,000/mm3; blood urea nitrogen, 9.0 mg/dL; and creatinine, 1.1 mg/dL. His electrolytes were normal.
Follow-up. Repeat CT scan 36 hours after admission showed urine extravasation and that the laceration extended to the collecting system. On the same day, the patient experienced a febrile seizure with a maximal temperature of 104°F (40°C) before the initiation of intravenous antibiotics that were ordered for the urine extravasation. Maximal blood pressure elevation (12021/86 mm Hg) also occurred that day.
The rest of his hospital stay was uneventful. The athlete received a percutaneous nephrostomy tube on hospital day 6, and he was discharged in excellent condition on day 9. The nephrostomy tube was removed 3 weeks after placement. He suffered no permanent sequelae. He could have returned to playing football 3 months later, but he did not participate the rest of the year. When he returned to training, he wore a flak vest during contact drills to prevent reinjury.
Injury to the kidney produces flank pain, hematuria (often but not always), and sometimes ecchymosis. Activities most often implicated include skiing, bicycle and motorcycle activities, equestrian sports, football, and mountain climbing.3 A direct blow to the flank or back is the most common mechanism of injury,3 and 80% of all renal injuries occur as a result of blunt trauma.4 The spectrum of injury ranges from benign contusions and minor lacerations (92% are contusions, 5% are lacerations, 2% are pedicle injuries) to potentially lethal ruptures (1%).5 Hematuria is the most visible sign of renal injury in athletes.6
Renal trauma in children is more common than in adults, possibly because children tend to have less developed musculoskeletal protection and proportionally larger kidneys than adults. Thirty percent of renal trauma in pediatric patients is sports-related, and kidney injuries are more common than spleen or liver trauma.7
Evaluation. Hematuria in athletes following vigorous activity is not uncommon. The first time an athlete is evaluated for this condition, whether it be gross or microscopic in nature, a serial urinalysis at 24 and 48 hours is important.8 If the urine clears, no further evaluation is necessary. Those with progressive symptoms such as flank pain, hematuria lasting more than 48 hours, gross hematuria, prolonged oliguria, or urinary casts need further evaluation with urine culture, imaging studies, and serum renal studies.8
The kidney may be only one of several organs that require immediate investigation in a traumatic situation, and this will affect the choice of imaging technique. According to Pollack and Wein,4 CT is the most informative radiologic study and the method of choice in cases of severe renal trauma, but it is not needed for stable, asymptomatic patients who have only minor, exclusively renal injuries. If urography alone does not provide adequate information for diagnosing minor injuries, CT may be the next step. Arteriography is used primarily for developing preoperative strategies and for therapeutic interventions, such as embolization of bleeding vessels and arteriovenous fistulas.4
Urography need not be the first study undertaken. Even with relatively minor injuries, CT is a better first choice because it is noninvasive. Rising creatine levels in a serum renal study are cause for alarm, but these are rarely seen. Usually the other kidney can take on the workload of the damaged one.
Treatment. Most urologists generally advocate conservative (nonoperative) management of renal injury for hemodynamically stable patients who do not have concomitant organ involvement.2,9 Conservative management consists of monitoring the patient's vital signs in a controlled hospital environment. If coexisting intraperitoneal trauma is present, surgical intervention may be recommended.9 Despite evidence that even severe renal injuries may be managed expectantly, injury to the renal pedicle requires surgical intervention.2
Although major surgery is often avoided in most renal injuries, many patients will require percutaneous intervention to prevent development of Page kidney, an accumulation of blood in the perinephric or subcapsular space that results in compression of the involved kidney, renal ischemia, and high renin hypertension.10 The name comes from a 1955 report by Engel and Page11 of a football player who suffered a subcapsular hematoma and subsequently developed hypertension. Page kidney tends to be found in previously well individuals who develop hypertension and who often have a history of blunt renal trauma.10 The pathophysiology of Page kidney is caused by effects on the renin (aldosterone) system, and treatment depends on the cause. Surgery will rarely be necessary, but fluid should be drained (if possible), and oral medication can be used if needed.
Return to play. An athlete may consider return to play 3 months after injury if follow-up CT shows a healed kidney and no residual hematuria is detected, according to Rashmi Patel, MD (oral communication, July 2021) and Steve Steinberg, MD (written communication, July 2021). For those who participate in contact or collision sports, a flak vest may be worn to provide additional protection, but no specific training considerations to prevent reinjury are necessary.
A high index of suspicion for renal injury is important for athletes and patients who have suffered blunt abdominal, flank, or lower-back trauma. Asking an athlete to produce a urine specimen for gross evaluation is easy, and the results are helpful in diagnosing patients who have persistent flank or back pain. Although hematuria is common, it is not absolute, and imaging studies are often necessary to uncover the true extent of damage. Even seemingly minor insults can result in lifelong complications, such as Page kidney. Minor surgical intervention, such as nephrostomy tube placement, should be considered if an injury produces extrinsic pressure on the renal parenchyma. Athletes who play high-risk positions (eg, quarterback in football) can wear a flak vest to help prevent reinjury.
Dr Wexler is a clinical assistant professor of family medicine in the Department of Family Medicine at The Ohio State University College of Medicine and Public Health in Columbus, Ohio, and Dr Parmar is a physician in the Department of Family Medicine at Oregon Health Sciences University in Portland. Address correspondence to Randell K. Wexler, MD, Dept of Family Medicine, 2231 North High St, Columbus, OH 43201; e-mail to [email protected].
Disclosure information: Drs Wexler and Parmar disclose no significant relationship with any manufacturer of any commercial product mentioned in this article. No drug is mentioned in this article for an unlabeled use.