Risk factors for upper tract deterioration in chronic spinal cord injury patients.

A total of 140 patients with neurogenic voiding dysfunction secondary to chronic spinal cord injuries was assessed initially at a tertiary care urodynamic center an average of 8 years after the acute injury. As a result of testing patients were divided into 2 functional urodynamic groups. Group 1 included 40 patients with an areflexic bladder, of whom 33 maintained normal upper tracts and 7 had significant upper tract deterioration. Group 2 included 100 patients with a hyperreflexic bladder, of whom 84 maintained normal upper tracts and 16 had documented upper tract deterioration. Maximum detrusor pressure during urine storage in group 1 with abnormal upper tracts was significantly higher than in those with normal kidneys (p less than 0.0001). Maximum detrusor contraction pressure during voiding in group 2 was significantly higher in those with abnormal upper tracts secondary to neurogenic outflow obstruction (p less than 0.0001). The most common outflow problem in this group was type 3 detrusor-sphincter dyssynergia. With guidelines thus developed for acceptable detrusor pressure in both types of bladder, silent upper tract damage can probably be prevented in most cases by proper and diligent followup and appropriate intervention, avoiding major morbidity and mortality in these high risk patients.