Bladder pain syndrome: Prevalence and routine clinical practice in women attending functional urology and urodynamics units in Spain. / Síndrome de dolor vesical: prevalencia y práctica clínica habitual en mujeres que acuden a Unidades de Urología Funcional y Urodinámica en España.

INTRODUCTION AND OBJECTIVES: Bladder pain syndrome (BPS) is classified as a rare chronic debilitating disease and its diagnosis presents a challenge because its symptoms overlap with those associated with overactive bladder syndrome. The aim of the routine study was to estimate the prevalence of BPS and discover to study the profile of symptoms and clinical practice for patients attending functional urology and urodynamics units. MATERIAL AND METHODS: An epidemiological study in which 37 functional urology and urodynamics units in Spain participated. The prevalence was studied in both sexes. Clinical practice was evaluated for 319 women with BPS (new diagnosis or under review). Clinical and sociodemographic data were collected retrospectively. The results were studied of urine tests, cystoscopy, biopsy, physical examination, bladder diary, and those of the four available questionnaires: Patient Perception of Bladder Condition; Bladder Pain/Interstitial Cystitis Symptom Score; EuroQoL-5 Dimensions-5L and Patient Global Impression of Severity. RESULTS: Five point four percent (503) of the patients who attended these units (9,312) had a diagnosis of BPS (90% [453] females). The tests that were performed most according to the clinical history and anamnesis were: urine test, bladder ultrasound and cystoscopy. The most common symptoms/comorbidities were: pain in the bladder region, increased urinary frequency, nocturia, anxiety and depression. Diagnostic assessment determined pain on hydrodistension (86.9%), positive biopsy (59.2%), myofascial pelvic pain (28.4%), urological phenotype (97.8%), and increased urinary frequency (88.7%). The questionnaires reflected how much the quality of life of these patients was affected. CONCLUSIONS: The prevalence of BPS in functional urology and urodynamics units in Spain is low. No homogeneity was observed in terms of diagnosis between the different participating centres. Therefore, a common methodology is required for the management of patients with BPS in these units, with tools specific to this disorder.

Virulence evolution in response to anti-infection resistance: toxic food plants can select for virulent parasites of monarch butterflies.

Host resistance to parasites can come in two main forms: hosts may either reduce the probability of parasite infection (anti-infection resistance) or reduce parasite growth after infection has occurred (anti-growth resistance). Both resistance mechanisms are often imperfect, meaning that they do not fully prevent or clear infections. Theoretical work has suggested that imperfect anti-growth resistance can select for higher parasite virulence by favouring faster-growing and more virulent parasites that overcome this resistance. In contrast, imperfect anti-infection resistance is thought not to select for increased parasite virulence, because it is assumed that it reduces the number of hosts that become infected, but not the fitness of parasites in successfully infected hosts. Here, we develop a theoretical model to show that anti-infection resistance can in fact select for higher virulence when such resistance reduces the effective parasite dose that enters a host. Our model is based on a monarch butterfly-parasite system in which larval food plants confer resistance to the monarch host. We carried out an experiment and showed that this environmental resistance is most likely a form of anti-infection resistance, through which toxic food plants reduce the effective dose of parasites that initiates an infection. We used these results to build a mathematical model to investigate the evolutionary consequences of food plant-induced resistance. Our model shows that when the effective infectious dose is reduced, parasites can compensate by evolving a higher per-parasite growth rate, and consequently a higher intrinsic virulence. Our results are relevant to many insect host-parasite systems, in which larval food plants often confer imperfect anti-infection resistance. Our results also suggest that - for parasites where the infectious dose affects the within-host dynamics - vaccines that reduce the effective infectious dose can select for increased parasite virulence.