Sphincter incontinence: is regenerative medicine the best alternative to restore urinary or anal sphincter function?

Incontinence is a major public health concern in aging societies. It is caused by age-dependent spontaneous apoptosis of muscle cells in the urinary and fecal sphincters, and is aggravated in women due to birth trauma. Compared to other currently employed invasive surgical management techniques associated with morbidity and recurrence, replacement or regeneration of dysfunctional sphincter through stem cell therapy and tissue engineering techniques hold great promise. This review focuses on the pathophysiological analysis of urinary incontinence and the possible application of muscle-derived-stem cells, satellite cells, chondrocytes and adipose-derived-stem cells in restoring sphincter functions.

[Impact of urinary incontinence in community-dwelling women]

Urinary incontinence (UI) is a frequent problem in an aging population and prevalence of urinary incontinence for elderly women may be up to 50% and imposes a huge burden on the health care system comparable to osteoporosis or osteoarthritis. The impact of UI shows clear associations between UI and depression and decline of quality of life comparable to congestive heart failure, major respiratory condition or gastrointestinal tract conditions. Some limited data suggest that UI is also a risk factor for institutionalization and hospitalization. Despite effective treatments, UI is significantly underdiagnosed by clinicians, and underreported by patients. This results in unmet needs for incontinence treatment, in particular for older individuals.

Intraobserver and interobserver agreement in the diagnosis of anal sphincter tears by postpartum endosonography

OBJECTIVE

To evaluate intraobserver and interobserver agreement in the diagnosis of anal sphincter tears by endosonography when performed immediately postpartum by resident obstetricians.

METHODS

Fifty-four primiparous women who delivered vaginally and had no anal sphincter tears (third- or fourth-degree perineal tears) diagnosed clinically were recruited. Four observers assessed photographic prints and video recordings of anal endosonography performed before the suture of the perineum. We calculated the intra- and interobserver agreement and the kappa coefficient to quantify the reliability of the diagnosis of clinically occult sphincter tears.

RESULTS

The observers described sphincter tears in 13-28% of the prints, and in 7-32% of the video recordings. Intraobserver agreement was rated as substantial for prints (kappa, 0.63), and moderate for video recordings (kappa, 0.48). The interobserver agreement was fair for prints (kappa, 0.34) and moderate for video recordings (kappa, 0.42).

CONCLUSION

Endosonography performed immediately postpartum to diagnose anal sphincter tears is of moderate reliability.

Prevalence of anal incontinence and other anorectal symptoms in women

We studied the prevalence of anal incontinence and other anorectal symptoms in women and evaluated the proportion of those who had sought medical help. A structured questionnaire was distributed to 1228 women attending the obstetrics and gynecology outpatient clinics (general, antenatal, urogynecology) of our university hospital. We also screened an additional sample of 984 women, representative of the general population aged 35-74. The prevalence of anal incontinence was 5.6% in the general outpatient clinic, 6.7% in the antenatal clinic, 15.9% in the urogynecology clinic and 4.4% in the general population. Only 20% of women affected by anal incontinence from the general outpatient clinic had reported their symptoms to a medical practitioner. Anal incontinence affects many women, but only a minority seek help. Obstetriciangynecologists should systematically inquire about the presence of this symptom.

Does a second delivery increase the risk of anal incontinence?

OBJECTIVE

To evaluate the prevalence of anal incontinence and anal sphincter defects after a first vaginal delivery and assess the effect of a second delivery.

DESIGN

Prospective cohort study using postal questionnaires assessing incontinence to flatus and stools at three and thirty months postnatally and anal endosonography at three months following delivery.

SETTING

Recruitment was from the antenatal clinic at the University Hospitals of Geneva, Switzerland.

POPULATION

One hundred women with a vaginal delivery of their first child.

MAIN OUTCOME MEASURES

Prevalence of anal incontinence and anal sphincter defects.

RESULTS

Anal incontinence was reported by 16/92 (17%) of women at three months after delivery and by 11/77 (14%) at 30 months. At that time, 5/54 (9%) with no further delivery reported incontinence, compared with 6/ 23 (26%) of those who had had another delivery (RR 2.8, 95% CI 1.0-8.3). Anal sphincter defects were diagnosed by endosonography in 46/87 (53%) women and were associated with reported incontinence at both three months (RR 1.9; 95% CI 1.4-2.6) and 30 months (RR 1.9: 95% CI 1.3-2.8) after delivery. The prevalence of anal incontinence at 30 months was highest (5/13, 39%) among those in whom a sphincter defect was diagnosed by endosonography after their first delivery and with a second delivery.

CONCLUSION

Anal incontinence after childbirth is associated with defects of the anal sphincter diagnosed by endosonography. Subsequent deliveries increase the risk of incontinence, particularly among women with a sphincter defect diagnosed after the first delivery.

Diagnosis of anal sphincter tears by postpartum endosonography to predict fecal incontinence

OBJECTIVE

To determine whether anal endosonography immediately after vaginal delivery can predict subsequent fecal incontinence.

METHODS

We studied nulliparas who delivered vaginally and had no anal sphincter tears (third- or fourth-degree perineal tears) diagnosed clinically by endosonography before any suture of the perineum. The sonographer was unaware of delivery details and the obstetrician and the women were not informed of endosonography results. Therefore, the suture of the perineum and the outcomes were not influenced by sonographer's diagnoses. Three months after delivery, we assessed fecal incontinence by self-administered questionnaires.

RESULTS

Clinically undetected tears of the anal sphincter were diagnosed by anal endosonography in 42 of 150 women (28%). The external anal sphincter alone was involved in 30 women (20%), the internal anal sphincter alone in two (1.3%), and both in ten (7%). The postal questionnaire was returned by 144 women. Incontinence was reported by 22 (15%, 95% confidence interval [CI] 10%, 22%), consisting mainly of incontinence to flatus only (16 of 22, 73%, 95% CI 50%, 89%). Clinically undetected anal sphincter tears diagnosed by endosonography were associated with incontinence 3 months after delivery (odds ratio [OR] 8.8; 95% CI 2.9, 26.5). The sensitivity of anal endosonography was 68% (95% CI 49%, 88%) and the positive predictive value 37% (95% CI 22%, 51%).

CONCLUSION

Anal endosonography immediately after vaginal delivery allows diagnosis of clinically undetected anal sphincter tears that might be associated with subsequent fecal incontinence.

Lung mechanics and pulmonary but not systemic vascular responses to ET-1 are Tx and infusion rate dependent

The role of cyclooxygenase metabolites formation in the systemic and pulmonary vascular and airway responses to different intravenous infusion rates of endothelin-1 (ET-1) was investigated in eight barbiturate-anesthetized mechanically ventilated adult sheep. ET-1 (20, 200, and 400 pmol/kg) was infused into the femoral vein over either 1, 10, or 180 s before and after pretreatment with indomethacin (1.5 mg/kg i.v.). ET-1 infusion produced a dose-dependent systemic vasoconstriction that was similar with all three infusion rates. In contrast, the pulmonary vascular and airways responses to ET-1 were not only dose dependent but also infusion rate dependent so that consistent effects on the pulmonary vasculature and airways were observed only when the peptide was injected over 1 s. At the highest dosage and at the fastest rate of administration, ET-1 produced a fivefold rise in pulmonary vascular resistance, a twofold rise in airway resistance, and a 45% decrease in dynamic pulmonary compliance, whereas no changes were observed when the peptide was injected over 180 s. Plasma levels of 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha) increased 20-fold when ET-1 was administered over 1 s but only 5-fold when it was administered over 180 s. Thromboxane B2 (TxB2) increased 5-fold when ET-1 was administered over 1 s and did not increase when ET-1 was given over 180 s. Plasma TxB2 levels were linearly correlated with pulmonary vascular or airway resistance during the bolus ET-1 infusion. Pretreatment with indomethacin completely prevented the ET-1-induced rise in TxB2 and 6-keto-PGF1 alpha and blocked pulmonary vaso- and bronchoconstriction observed, whereas it enhanced systemic vasoconstriction. These results demonstrate that in adult sheep intravenous ET-1 produces pulmonary vaso- and bronchoconstriction that is infusion rate dependent and is associated with the rate-dependent production of thromboxane. In contrast, the increase in systemic vascular tone elicited by ET-1 is not affected by its rate of infusion and does not depend on the secondary generation of cyclooxygenase metabolites.

The decrease in organ donations from 1985 to 1990 caused by increasing medical contraindications and refusals by relatives

After the progressive improvement in the results of organ transplantation we now face the challenge of shortage in organ supply. The decreasing number of organ retrievals performed in 1990 at our hospital has raised questions concerning loss of potential organ donors and opposition to donation by the next of kin. We investigated these questions and the number of organs available per million inhabitants in the area covered by our university hospital. Our surgical intensive care unit provides about 85% of all organ donations for this area. To this end, all 375 deaths occurring in the surgical ICU during the period between January 1, 1985 and December 31, 1990 were analyzed. Of 138 brain-stem deaths, 43 presented medical contraindications preventing organ harvesting for transplantation. Consent for donation was sought from the families of the 95 remaining potential donors and was refused for 17 patients. Organ retrieval followed all of the 78 agreements to donate, so that no suitable donor was lost. Over the 6 years surveyed, a progressive decrease in organs procured was observed, due to an increase of medical contraindications to organ harvesting for transplantation (P less than 0.001) and a higher rate of refusals to donate organs (P less than 0.002). The rate of kidney retrieval was thereby reduced from 45 to less than 25 per million population per year between 1985 and 1990 for our hospital's catchment area. The reasons cited by the families for denying organ donation suggest that the publicity campaigns aimed at the medical community and the public concerning organ transplant programs should be modified, and that a careful selection of indications for transplantation seems mandatory.