Clinical staging of ketamine-associated urinary dysfunction: a strategy for assessment and treatment.

PURPOSE: To describe a clinical staging method linked to stepwise treatment indications for ketamine-associated urinary dysfunction (KAUD) based on review of our experience in management of KAUD patients and analysis of their clinical features. METHODS: The eighty-one KAUD patients hospitalized from January 2008 to June 2014 were studied retrospectively. According to ketamine history, renal and liver function, bladder change and up urinary tract involvement, patients were categorized into a described model of three stages. Discriminant analysis was applied to validate the model. The void volume, micturition interval, nocturnal void frequency and pelvic pain and urgency/frequency (PUF) questionnaire score were, respectively, compared after treatments. RESULTS: There were, respectively, 24, 47 and 10 patients in three stages. The duration of abuse varied (p = 0.047) correlated with clinical stages (p = 0.015, r = 0.268). The severity of LUTS was not significant. The creatinine, estimated glomerular filtration rate and liver function were worse in higher stages (p < 0.01), and the incidence of ureteral change and hydronephrosis was greater (p < 0.001). Based on the model, cross-validation confirmed 83.1 % cases were classified correctly. Twenty-four patients in stage I were treated with behavioral modification and pharmacotherapy, thirty-five patients in stage II with hydrodistention and six patients in stage III with surgical intervention due to rapid progression after conservative therapy. All patients in three stages demonstrated improvements in void volume, micturition interval, nocturnal void frequency and PUF score (all p < 0.05) after treatment. CONCLUSION: Clinical staging could serve for assessment of progression, and the staging-based treatment is effective. This model still awaits further validation.