Congenital Bladder Anomalies
The two most common congenital bladder abnormalities are exstrophy and congenital diverticula. An exstrophic bladder is one that is open to the outside and turned inside out, so that its inside is visible at birth, protruding from the lower abdomen. A diverticulum is an extension of a hollow organ, usually shaped like a pouch with a narrow opening.
During fetal development, folds enclose tissues and organs and eventually fuse at the edges to form sealed compartments. Both in the front and the back, folds eventually become major body structures. In the back, the entire spinal column folds in like a pipe wrapped in a pillow. In the front, the entire lower urinary system is folded in.
Exstrophy of the bladder represents a failure of this folding process to complete itself, so the organs form with more or less of their front side missing and remain open to the outside. At the same time, the front of the pelvic bone is widely separated. The abdominal wall is open, too. In fact, the defect often extends all the way to the penis in the male or splits the clitoris in the female.
A congenital bladder diverticulum represents an area of weakness in the bladder wall through which extrudes some of the lining of the bladder. (A small balloon squeezed in a fist will create diverticula-like effect between the fingers.) Bladder diverticula may be multiple, and they often occur at the ureterovesical junction (the entrance of the upper urinary system into the bladder). In this location, they may cause urine to reflux into the ureter and kidney, leading to infection and possible kidney damage.
Exstrophy is rare, occurring once in approximately 40,000 births.
Causes and symptoms
As with many birth defects, the causes are not well known. Lack of prenatal care and nutrition has been linked to many birth defects; however, beyond the avoidance of known teratogens (anything that can cause a birth defect), there is little prevention possible. Diverticula are more common and less serious.
If left untreated, the person with bladder exstrophy will have no control over urination and is more likely than others to develop bladder cancer. Diverticula, particularly if it causes urine reflux, may lead to chronic infection and its subsequent consequences.
A major consideration with congenital abnormalities is that they tend to be multiple. Further, each one is unique in its extent and severity. Exstrophy can involve the rectum and large bowel and coexist with hernias. The obvious bladder exstrophy seen at birth will prompt immediate action and a search for other anomalies.
Diverticula are not visible and will be detected only if they cause trouble. They are usually found in an examination for the cause of recurring urinary infections. X rays of the urinary system or a cystoscopy (examination with a telescope-like instrument) will identify them. Often, the two procedures are done together: a urologist performs the cystoscopy, then a radiologist instills a contrast agent into the bladder and takes x rays.
Surgery is necessary and can usually produce successful results. If possible, the surgery must be performed within 48 hours of birth. Prior to surgery, the exposed organs must be protected and all related defects identified and managed. Delay in the surgery leads to the frequent need to divert the urine into the bowel because the partially repaired bladder cannot control the flow. After surgery, the likelihood of infection requires monitoring.
After surgery, ongoing precautions to reduce frequency of infection may have to be used. Cranberry juice
With immediate surgery, three-fourths of all people can be successfully repaired. They will have control of their urine and no long-term consequences. The rate of infection is greater for those with congenital bladder anomalies, since any abnormality in the urinary system predisposes it to invasion by bacteria.
Birth defects often have no precisely identified cause; therefore, prevention is limited to general measures such as early and continuous prenatal care, appropriate nutrition, and a healthy lifestyle.
Parents must monitor the urinary output of their newborn children for the first few days of life. Parents of children with bladder diverticula should be aware of prevention and treatment practices for urinary tract infections.
Congenital—Present at birth.
Cystoscopy—A diagnostic procedure in which a hollow lighted tube (cystoscope) is used to look inside the bladder and the urethra.
Diverticulum—Plural, diverticula; an outpouching in a tubular organ caused when the inner, lining layer bulges out (herniates) through the outer, muscular layer. Diverticula are present most often in the colon (large intestine), but are also found in the bladder.
Exstrophy—A congenital condition in which a hollow organ, such as the bladder, is turned inside out, establishing contact between the organ and the outside of the body.
Radiologist—A medical doctor specially trained in radiology, the branch of medicine concerned with radioactive substances and their use for the diagnosis and treatment of disease.
Teratogen—Any drug, chemical, maternal disease, or exposure that can cause physical or functional defects in an exposed embryo or fetus.
Ureter—The tube that carries urine from the kidney to the bladder; each kidney has one ureter.
Ureterovesical junction—The point where the ureter joins the bladder.
Urologist—A physician who specializes in the anatomy, physiology, diseases, and care of the urinary tract (in men and women) and male reproductive tract.
See also Cystitis.
Asplin, John R., and Fredric L. Coe. "Hereditary Tubular Disorders." In Harrison's Principles of Internal Medicine, 15th ed. Edited by Eugene Braunwald et al. New York: McGraw-Hill, 2001, pp. 1598–1605.
Elder, Jack S. "Anomalies of the Bladder." In Nelson Textbook of Pediatrics, 17th ed. Edited by Richard E. Behrman, et al. Philadelphia: Saunders, 2003, pp. 1804–5.
Guay-Woodford, Lisa M. "Anomalies of the urinary tract." In Cecil Textbook of Medicine, 22nd ed. Edited by Lee Goldman et al. Philadelphia: Saunders, 2003, pp. 772–4.
Tanagho, Emil A., and Jack W. McAnich. Smith's General Urology. New York: McGraw-Hill, 2003.
Caire, J. T., et al. "MRI of fetal genitourinary anomalies." American Journal of Roentgenology 181, no. 5 (2003): 1381–5.
Carr, M. C. "Prenatal management of urogenital disorders." Urology Clinics of North America 31, no. 3 (2004): 389–97.
Greenwell, T. J., et al. "Pregnancy after lower urinary tract reconstruction for congenital abnormalities." British Journal of Urology International 92, no. 7 (2004): 773–7.
Tsuchiya, M., et al. "Ultrasound screening for renal and urinary tract anomalies in healthy infants." Pediatrics International 45, no. 5 (2003): 617–23.
American Academy of Family Physicians. 11400 Tomahawk Creek Parkway, Leawood, KS 66211–2672. Web site: <www.aafp.org/>.
American Academy of Pediatrics. 141 Northwest Point Blvd., Elk Grove Village, IL 60007–1098. Web site: <www.aap.org/default.htm>.
American Foundation for Urologic Disease. 1128 North Charles St., Baltimore, MD 21201. Web site: <www.afud.org/>.
American Urological Association.1000 Corporate Boulevard Linthicum, MD 21090. Web site: <www.auanet.org>.
"Bladder Anomalies." eMedicine. Available online at <www.emedicine.com/ped/topic1402.htm> (accessed December 21, 2004).
"Pediatric Urologic Problems>" Department of Urology/Mount Sinai School of Medicine. Available online at <www.mssm.edu/urology/patient_care/pediatric_urologic_problems.shtml> (accessed December 21, 2004).
L. Fleming Fallon, Jr., MD, DrPH