Bladder dysfunction in human T cell lymphotropic virus infection: A prospective cohort study

Background While bladder dysfunction is observed in the majority of patients with human T cell lymphotropic virus type 1 (HTLV-1)-associated myelopathy (HAM), it is also observed in patients who do not fulfill all diagnostic criteria for HAM. These patients are classified as having possible or probable HAM/TSP. However, it remains unclear whether the severity and progression of bladder dysfunction occurs similarly between these two groups. Objective Compare the severity and evolution of bladder dysfunction in HTLV-1-infected patients with possible and definite HAM/TSP. Methods The present prospective cohort study followed 90 HTLV-1 patients with possible HAM/TSP and 84 with definite HAM/TSP between April 2011 and February 2019. Bladder dysfunction was evaluated by bladder diary, overactive bladder symptoms scores (OABSS) and urodynamic studies. Bladder dysfunction progression was defined as the need for clean self-intermittent catheterization (CIC). Results At baseline, nocturia, urgency and OABSS scores were worse in definite compared to possible HAM/TSP patients. The main urodynamic finding was detrusor overactivity, present in 77.8% of the patients with definite HAM/TSP versus 58.7% of those with possible HAM/TSP (P = 0.05). Upon study conclusion, the cumulative frequency of patients requiring CIC increased in both groups, from 2 to 6 in possible HAM/TSP and from 28 to 44 in definite HAM/TSP patients. The estimated time to need for CIC was 6.7 years (95%CI 6.5–7.0) in the possible HAM/TSP group compared to 5.5 years (95%CI 4.8–6.1) in the definite HAM/TSP group. Conclusions Although both groups showed similarities in bladder dysfunction and tended to progress to requiring CIC over time, patients with possible HAM/TSP presented less severe manifestations at baseline and progressed more slowly than those with definite HAM/TSP.

Remyelination Improves Voiding Dysfunction in a Mouse Model of Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS). Of note, over 80% of MS patients have urinary symptoms as one of their earliest symptoms. Since MS patients often live into older age, urinary incontinence and retention are significant problems affecting their quality of life. Although several studies show that inflammatory-demyelinating animal models of MS develop bladder dysfunction, the confounding influence of systemic inflammation in these models limits potential interpretation on the contribution of CNS-myelination to bladder dysfunction. We sought to address this knowledge gap using the cuprizone model of demyelination and remyelination. C57Bl/6 mice were treated with dietary cuprizone (0.2%w/w) for four weeks to induce demyelination. One group was allowed four additional weeks for recovery and remyelination. We performed voiding spot assay (VSA), urethane-anesthetized cystometry, and CNS-histology to assess demyelination-induced differences in urinary performance. We observed that cortical demyelination causes significant aberrance in voiding behavior (conscious cortical control) characterized by increased micturition frequency and reduced volume per micturition. Interestingly, remyelination restored healthy bladder function. However, there were no significant changes in the cystometric parameters (brainstem reflex) between the treatment groups. While MS is not classically considered a disease of aging, extending the longevity of these patients has not been reciprocated with improved treatments for their most-bothersome conditions, notably urinary symptoms that persist throughout life. Our data represent a novel compelling connection and strong correlation between CNS-myelination and cortical control of bladder function, which has potential implications in MS, aging, and aging-associated neurological disorders.