Renal Trauma

Pediatric GU Review

UCSD Pediatric UrologyGeorge Chiang MD

Sara Marietti MD

Outlined from The Kelalis-King-Belman Textbook of Clinical Pediatric Urology 2007

(not for reproduction, distribution, or sale without consent)

Pediatric Renal Trauma

• Most commonly injured abdominal organ in blunt trauma– Fetal lobulations predispose to renal separation– Less protection by pliable thoracic cage and less

developed musculature– Higher incidence of pedicle injury

• 80% with renal injury have associated nonrenal injuries

Pediatric Renal Trauma

• Shock unreliable indicator of significant injury• Controversy exists when to image pediatric

renal trauma patients.• Some advocate imaging ALL ALL children with

microscopic hematuria• Dr. Morey and others have suggested

observation in stable patients with <50rbc/hpf and mild trauma

Mechanisms of Injury

• Blunt trauma– 85-95% of renal trauma– Direct blow / Assault– Bony spicules of ribs or

vertebrae– MVA: speed; driver,

passenger, degree of deceleration

– Falls

Giambologna, Hercules and the Centaur, 1550

Mechanisms of Injury• Penetrating trauma

– ~ 10% of renal trauma– Gunshot injury from bullet, – fragments, or blast effect– Stab wounds: size of knife– KE = ½ MV2

Mantegna, St. Sebastian, 1470

Pediatric Renal Trauma

• Preexisting renal abnormalities (i.e. UPJ Obstruction, hydro, horseshoe kidney) are 3-5 X more common in peds patients undergoing screening CT for trauma than in adults

• Classically, congenital renal abnormality presents with hematuria disproportionate to severity of trauma

( Chopra et al, 2002 ; McAleer et al, 2002 ; Heyns, 2004 ; Santucci et al, 2004).

American Association for the Surgery of Trauma Organ Injury Severity Scale for the Kidney

Grade Description of Renal Injury

I Contusion : hematuria with normal radiological studies.

Hematoma : subcapsular and non expanding. 

II Hematoma  : perirenal ,confined to retroperitoneum. 

Laceration  :  < 1 cm depth without extravasation

IIILaceration  :  > 1cm depth without collecting system injury or extravasation. 

IV Laceration : through renal cortex, medulla, collecting system. 

  Vascular : renal artery or vein injury : contained hemaorrhage. 

V Laceration : shattered destroyed kidney 

  Vascular    : renal arterial and venous avulsion. 

Moore, Shackford, J Trauma, 1989

Organ Injury Scale

Hematuria in Children

• Unreliable in determining who to screen for renal injuries

• Some studies have failed to find any evidence of either gross or microscopic hematuria in up to 70% of children sustaining grade 2 or higher renal injury.

• Hematuria alone cannot determine need for radiographic studies

( Morey et al, 1996 ; Buckley and McAninch, 2004 ).

Radiographic Trauma Assessment1. All penetrating abdominal trauma, 2. Blunt trauma victims who have either:

• Significant deceleration or high-velocity injury • fractures of thoracic rib cage, spine, pelvis, or

femur, or bruising of the torso/perineum, or signs of peritonitis

• Gross hematuria • Microscopic hematuria (>50 red blood cells per

high-powered field) and shock (SBP<90mm Hg)

Santucci and associates (2004a)

J Pediatr Surg. 2002 May;37(5):779-82 Chopra P, et al. (Montreal, Quebec)

PURPOSE: quantify pathologic lesions of the kidney found incidentally during blunt trauma w/u

METHODS: Retrospective review of 103 patients (0 to 18 years) with blunt renal injuries.

• US in all cases and CT as indicated

RESULTS: Coexisting urogenital lesions were identified in 13 of 103 (12.6%) patients, and 7 (54%) required surgical treatment.

• Majority - 9 of 13 (69%) suffered minimal trauma. • Gross hematuria was main symptom. • UPJ Obstruction was most common anomaly

CONCLUSIONS: Pathologic lesions of the urinary tract are uncommon; however, they may complicate an otherwise negligible renal trauma.

Brown SL, et al. in World J Surg. 2001 Dec;25(12):1557-60 Radiologic evaluation of pediatric blunt renal trauma in patients

with microscopic hematuria.

• Reviewed 1200 children with blunt abdominal trauma, 35 had CT

Results• 3 with grade II-V renal injuries, 32 were normal or had renal contusions • 1/3 patients with gross hematuria evaluated with CT sustained significant renal

injury without other associated injuries.

Conclusions:• The degree of hematuria did not correlate with the grade of renal injury. • Pediatric patients with blunt trauma, microscopic hematuria, and no associated

injuries do not require radiologic evaluation, as significant renal injuries are unlikely.

• However, children who present with associated injuries and microscopic hematuria after blunt trauma may have significant renal injuries and should undergo radiologic evaluation.

• Methods:– 14,763 pts reviewed

• Results:– 193 with imaging or direct evidence of renal injury at surgery (32)– 69% had associated injuries– 17 (8.3%) congenital GU anomalies found in series

• CONCLUSIONS:– 1.3% of pediatric trauma pts have renal injuries– 8.3% had congenital anomalies– UPJ Obstruction was most common abnormality (~33%) – Congenital anomalies may not increase risk of morbidity due to

renal trauma

Master, McAnich; Urol Clin N Am, 2006

Master, McAnich; Urol Clin N Am, 2006

Master, McAnich; Urol Clin N Am, 2006

Master, McAnich; Urol Clin N Am, 2006

Master, McAnich; Urol Clin N Am, 2006