[Clinico-urodynamic correlation in the hereditary ataxias]

To evaluate lower urinary tract functional symptoms in a series of patients with ataxia and to determine by urodynamic studies the kind of bladder-urethra neurological dysfunction in each case. We posed the question if the clinical picture could be enough to establish the diagnosis and therapeutic management of these patients with hereditary ataxia, or on the contrary it would be necessary to perform urodynamic studies in all cases.

Due to the low incidence of hereditary ataxias and patients' mobility it was necessary to recruit patients from various hospitals. The urodynamic study protocol employed in this study included 1) Evaluation of urinary symptoms; 2) Neurological physical examination; 3) Flowmetry with post void residual; 4) Cystomanometry; and 5) Perineal electromyography. We analyzed the relationship between urinary symptoms and urodynamic diagnosis, considering variables such as age, gender, type of ataxia, and time of evolution of the disease.

The series includes 34 patients with ataxia and urinary symptoms, 14 cases of Friedreich's ataxia (FA) (41.2%) and other 20 cases of other various forms of ataxia we name non-Friedreich's (NF) (58.8%). Mean age was 37.2 years in FA and 50 years in NF (p < 0.05). Mean time of disease evolution was 20.5 yr. for FA, and 14.9 yr. for NF ataxia (p < 0.1). A mixed urinary syndrome was predominant in 53% of the patients, and 41.1% presented pure irritative symptoms in relation to voiding urgency (85.2%). The most frequent urodynamic diagnosis was detrusor hyperreflexia (61.7%) (37.5% with dyssynergia), followed by areflexia (or hyporeflexia) (23.5%), and normal studies (14.7%). Detrusor hyperreflexia presented with irritative urinary symptoms in 85.7% of the patients, and areflexia or hyporeflexia presented with obstructive symptoms in 75% of the cases.

Although there is a good clinical-urodynamic correlation in cases of ataxia, we consider it is necessary to perform a complete urodynamic study in males with hereditary ataxia in order to rule out bladder outlet obstruction due to BPH. On the other hand, due to the fact that progression of the lesions can modify the clinical picture of the patient (including urinary tract symptoms), we consider essential to re-evaluate ataxic patients periodically to adapt their treatment to the urodynamic diagnosis.