Continuous overnight monitoring of bladder activity in vesicoureteral reflux patients: II. Bladder activity types

Micturition is associated with phase III of the interdigestive migrating motor complex in man

OBJECTIVES

In previous manometric studies, we observed that micturition was associated with phase III of the migrating motor complex. The present study aimed to objectify this possible relationship and to examine whether modulation of micturition frequency influences migrating motor complex phase III incidence.

METHODS

In a retrospective study, ambulatory antroduodenal manometry and micturition data of 27 subjects were analyzed. In a prospective study, antroduodenal motility and micturition patterns were studied in five subjects who were subjected to an oral water load. Volunteers were either allowed to micturate ad libitum or instructed to postpone micturition.

RESULTS

In the retrospective part of the study, a statistically significant association was found between phase III and micturition. Of all micturitions, 50% took place during or within 10 min from phase III. Also, in the prospective part of the study, phase III and micturition, as well as micturition urge, showed a significant association (p < 0.05).

CONCLUSION

Micturition and phase III of the migrating motor complex are associated in time.

Sleep of children with enuresis: a polysomnographic study

OBJECTIVE

To evaluate relationships between bladder voiding and sleep in children with enuresis.

METHODS

Polysomnographic recordings were obtained from 25 children, aged 7 to 17 years, with monosymptomatic nocturnal enuresis. During 52 recorded nights, 37 enuretic events were detected. Responders (n = 7) and nonresponders (n = 16) to desmopressin treatment were compared.

RESULTS

The mean latency between sleep onset and the first bladder voiding was 3 hours 20 minutes (SD = 2 hours 5 minutes). The number of voidings were 19, 7, 10, and 1 occurring during stages 2, 3, and 4, and rapid-eye movement sleep, respectively. Desmopressin responders were found to void during the early or late part of the night, whereas the voidings of the nonresponders were dispersed evenly throughout the night (chi2 = 8.09).

CONCLUSIONS

The enuretic event is a predominantly non-rapid eye movement sleep phenomenon. Responders and nonresponders to desmopressin treatment void during different parts of the night.

Uroflow in women: an overview and suggestions for the future

The literature on uroflowmetry in women is presented and evaluated. Uroflowmeters are described and found generally sufficiently accurate, although the errors arising from electronic evaluation may invalidate the test. Six flow curve patterns are proposed in accordance with described pathological conditions. From the literature it is summarized that the normal Qmax is 20-36 ml/s. Qmax is linearly correlated to the voided volume, increasing by 5.6 ml/s/100 ml. Pregnancy, age and menstrual cycle do not influence Qmax. Several pathological conditions have been associated with specific flow curve patterns. These conditions are described and associations with the proposed flow definitions made.

Uroflowmetry

Uroflowmetry is a widely used noninvasive screening modality for patients who present with symptoms of lower urinary dysfunction. However, it should be recognized that uroflowmetry represents the compound effect of bladder and urethral function because it may easily be misinterpreted. In elderly men with "prostatism", uroflowmetry is often sufficient to indicate treatment, while the value in women is less prominent. In pediatrics, more sophisticated urodynamic testing is crucial.

Vesicoureteric reflux and renal injury

Renal injury associated with the intrarenal reflux (IRR) of urine that is either infected, under high pressure, or both, is a major cause of severe hypertension during childhood and adolescence and of chronic renal insufficiency in patients less than 30 years of age. Many, but not all, adolescent and adult patients with reflux nephropathy (RN) give a history of urinary tract infection (UTI) or unexplained fevers in infancy or early childhood, when the kidney is thought to be at greatest risk of injury. Although vesicoureteric reflux (VUR) is observed more commonly in infants than children with UTI, it is rare in uninfected patients at any age and should never be considered a normal finding during human development. Renal scarring may not be obvious in radiographic or radionuclear studies to medical management alone, no definite benefit of one over the other was observed, regardless of the grade of VUR. Moreover, progressive renal injury in scarred kidneys has been noted even after VUR had been corrected, when infection had been prevented, and while hypertension had been controlled satisfactorily. Focal glomerular sclerosis, a lesion found in patients with proteinuria and RN, has been identified not only in scarred kidneys, but also may be seen in contralateral, unscarred kidneys without VUR, which might suggest a humoral factor or, perhaps, a hyperfiltration phenomenon. RN is one of the most frequent causes of end-stage renal disease (ESRD) in children, adolescents, and young adults, which is potentially preventable. However, prevention will depend on early identification of patients at risk--infants and young children after the first UTI and siblings of patients with VUR--aggressive and effective treatment of UTI, minimizing intravesical pressure, and education of patients, parents, and physicians.

Sleep cystometries in children with nocturnal enuresis

A combined analysis was done of sleep and bladder filling during sleep. Cystometry did not specifically affect sleep, since most of the cystometry studies in cases of enuresis did not lead to sleep stage changes on electroencephalography. Bladder instability was not accompanied by lighter sleep. Increasing patient age did not appear to have any influence on sleep or bladder behavior. We conclude that it is possible to provoke enuresis at any sleep stage and that sleep is unaffected by bladder filling in enuretic patients.

Vesico-uretero-renal reflux and the kidney

The most frequent complications of non-obstructive vesico-uretero-renal reflux (VUR) are segmental renal scars. These scars are confined to segments with intrarenal reflux which are, in addition, exposed to bacterial infection. Primarily, only gaping collecting duct orifices, confined to compound papillae and mainly situated at the kidney poles, allow intrarenal reflux. Scar contraction and obstruction seem to be able to transform closed collecting duct orifices into gaping ones, thereby enlarging the parenchymal area prone to intrarenal reflux and to renal scarring. Contrary to earlier reports, a recent survey has documented that new scars in children develop with significant frequency beyond 5 years of age. There is a greater tendency for scarring to develop with more severe VUR, but new renal scars can develop with all grades of VUR. Early and adequate antibiotic treatment decreases the extent of scarring. The results of experimental studies in which renal scarring developed in piglets with bladder decompensation resulting from intravesical obstruction but without bacterial infection may be relevant to the few children with proximal urethral valves and hypertonic neurogenic bladders but not to the large number with non-neurogenic detrusor instability or detrusor sphincter dyssynergia. Prospective studies have not shown different recurrence rates of urinary tract infections in medically managed compared with surgically managed children. The frequency of acute pyelonephritic attacks decreased significantly after operation.

Nonneurogenic neurogenic bladder (the Hinman syndrome)--15 years later

Every child with day and night wetting is a suspect for vesicourethral dysfunction on a behavioral basis, which, when severe, appears as a syndrome that we have called the nonneurogenic neurogenic bladder. Futile attempts by the child at sphincteric urinary control in the face of uncontrollable bladder contractions not only produce the symptoms but also the anatomical and functional changes: vesical trabeculation, distortion of the ureterovesical orifices and dilatation of the upper tracts, along with residual urine and consequent bacteriuria. These changes are indistinguishable from obstructive or, particularly, neurogenic factors, although these causes must be ruled out. Urodynamic investigations in these children show incoordination between detrusor contraction and the expected but not forthcoming urethral sphincteric relaxation. Since these children usually are toilet trained initially, the incoordination appears to be a learned behavior or habit, perhaps as a response to under-appreciated detrusor contractions. Reversal of the syndrome is achieved by suitable medication and by some form of suggestion or retraining. Reparative operations will fail if done before the system is balanced.

Enuresis as protective factor in vesicoureteral reflux

In 83 patients with non-neurologic, nonoperated vesicoureteral reflux the relation between enuresis and nephropathy was analyzed. The material showed that in spite of identical age, sex distribution, previous history of recurrent urinary tract infections, and the number of refluxing units, patients with enuresis showed a significantly lower degree of reflux nephropathy. This significant difference was even more pronounced when the age of the patients was considered. Thus patients below the age of ten showed reflux nephropathy in 25 per cent of the refluxing units in enuretic patients compared with 30.8 per cent in the nonenuretic patients. Above the age of ten 76.2 per cent of the refluxing units showed renal scarring in the nonenuretics compared with 27.8 per cent in the enuretics. The study stresses the importance of lower urinary tract malfunction in the pathogenesis of reflux. Enuresis might act as a safety valve mechanism reducing the possibility of reflux nephropathy.

Simultaneous registration of sleep-stages and bladder activity in enuresis

A combined monitoring of sleep stages and bladder activity for the evaluation of enuresis is on trial. Polygraphic recordings in 7 patients, comprising the preliminary material, have shown single-event bladder contractions without forewarning or changes in sleep stages. A volume dependency of the enuresis episodes seems so far to be a major mechanism.

The diagnosis of vesico-ureteral reflux. Radiologic and nuclear medicine methods

Video voiding cystourethrography in 47 patients was compared to 99mTc cystography performed suprapubically in 20 patients and 123I Hippuran renocystography performed in 43 patients. The degrees of reflux were equally distributed through the grades. 99mTc cystography was negative in 4 of 5 grade 2 refluxes and positive in 4 out of 5 grade 3-4 refluxes. Computerized dynamic tracings of the 123I renocystography showed an activity level increase over the kidneys of more than 1% of the bladder activity level in 47 units, 18 were equivocal and 21 negative. Grade 2 and 3 reflux found on the video VCU was refound on the renocystography. 24 false positives were found. It is concluded that 99mTc cystography performed as in our unit adds no further information to the diagnosis of reflux and that 123I renocystography diagnosing the more severe degrees of reflux may be a future method of non-invasive reflux control.

Dynamics of the urinary tract in longterm vesico-ureteric reflux and infravesical obstruction in pigs. IV

The dynamic function of the urinary tract was studied in 6 infravesically obstructed pigs with vesico-ureteric reflux to a total of 8 ureters. After 10 weeks of obstruction a bladder hyperreflexia was found. The baseline ureteric activity in the refluxing ureters was reduced to a median of 0.3 A.P./min (action potentials/min). During bladder filling, the activity increased only slightly to 0.6 A.P./min. In the start the pelvic pressure was more or less independent of the bladder pressure, but when the reflux producing bladder pressure was reached then an abrupt increase in pelvic pressure was seen and thereafter there was pressure equilibration. Ten weeks after release of the obstruction, a minor restitution had taken place. The baseline activity during low urine output was 1.0 A.P./min and during bladder filling it was unaltered, 1.0 A.P./min. Even during high urine output there was no sign of activity increase. 30% of the ureteric contractions stopped in the mid-third of the ureter. Almost all peristalsis was antegrade. Thus, ureters subjected to obstruction and reflux showed deterioration of the peristaltic function and the changes were irreversible.