Parurésie

Paruresis, also known as shy bladder syndrome, is a type of phobia in which a person is unable to urinate in the real or imaginary presence of others, such as in a public restroom. The analogous condition that affects bowel movement is called parcopresis or shy bowel. Some people have brief, isolated episodes of urinary difficulty in situations where other people are in close proximity. Paruresis, however, goes beyond simple shyness, embarrassment, fear of exposure, or fear of being judged for not being able to urinate. Other people may find that they are unable to urinate while in moving vehicles, or are fixated on the sounds of their urination in quiet restrooms or residential settings. In severe cases, a person with paruresis can urinate only when alone at home or through the process of catheterization. One possible cause of paruresis is undergoing a voiding cystourethrography (VCUG) in the past. "Complications that can occur in both sexes include UTI, hematuria, cystitis as well as urinary dysfunction following a catheterization, phobia of urination, nocturia, and stopping urination. In the literature, psychological trauma resulting from VCUG was considered the same as from a violent rape, especially in girls." It appears that paruresis involves a tightening of the sphincter or bladder neck due to a sympathetic nervous system response. The adrenaline rush that produces the involuntary nervous system response probably has peripheral and central nervous system involvement. The internal urethral sphincter (smooth muscle tissue) or the external urethral sphincter (striated muscle), levator ani (especially the pubococcygeus) muscle area, or some combination of the above, may be involved. It is possible that there is an inhibition of the detrusor command through a reflex pathway as well. The pontine micturition center (Barrington's nucleus) also may be involved, as its inhibition results in relaxation of the detrusor and prevents the relaxation of the internal sphincter.