Risk factors for renal injury in patients with meningomyelocele

Thirty operated patients of myelodysplasia were clinically evaluated for the age at presentation, the extent of lesion and neurological deficit. Urological assessment was done with urine cultures, serum creatinine, radiological (ultrasound of kidney, ureters and bladder, voiding cystourethrogram) and urodynamic (water cystometry) parameters. An objective scoring for bladder (Galloway, et al.) was applied. Dimercapto-succinic acid (DMSA) scan was done in all the patients for evidence of renal scars. The results of above investigations were correlated with presence or absence of renal scars (renal injury) on DMSA scan. None of the patients had received any prior bladder care.

Twenty one patients had no renal scars and 9 patients had evidence of renal scarring. Patients with renal scars were older at presentation, they had greater degree of hydroureteronephrosis (P < or = 0.001) and vesicoureteric reflux (P < or = 0.005). The incidence of high leak pressures (>25 cm of water, P < or = 0.05), unacceptable bladder volumes (maximum cystometric capacity < 60% for age, P < or = 0.005) and high risk Galloway's score (> 5, P < or = 0.05) was high in patients with associated renal scarring as compared to their nonscarred counterparts. Three of these patients had serum creatinine >1 mg/dl (P < or = 0.005). The incidence of urinary complaints and positive urine cultures was also higher in these patients (NS).

Increasing age, evidence of hydroureteronephrosis and vesicoureteric reflux, high leak pressures, low bladder volume and high combined Galloway score (>5) define a high risk bladder in our population and predispose to renal injury in patients of myelodysplasia. Early referral for bladder risk assessment and management of all myelodysplasia patients is recommended.