The observation that constipation alone may induce uninhibited bladder contractions in children and is associated with recurrent urinary tract infection in childhood suggests an etiologic association. Rectal distension due to faecal retention in chronic functional constipation causes bladder distortion and may cause stimulation of detrusor stretch receptors resulting in detrusor peroneal dyssynergism. Distortion of the trigonal area may result in failure of ureteral valve competence and allow for vesico-ureteric reflux.