Urinary tract infection

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A urinary tract infection, also commonly known as a UTI, is a bacterial infection in the urinary tract (kidneys, ureters, bladder and/or urethra). UTIs can affect both males and females, although, due to the difference in structures of the male and female urinary tract, infections occur most commonly in girls and women, as the urinary tract is shorter in females than it is in males. UTIs can become serious if undetected, and may lead to permanent kidney damage. However, they are easily and effectively treated with antibiotics.[1][2]

Contents

Causes

UTIs are often caused by Escherichia coli (E. coli) bacteria, to which the infant has no passive immunity. In infant girls UTIs generally originate in the colon, whereas in infant boys they originate from the external environment, strongly suggesting that for boys such infections are iatrogenic.[3] Although E. coli is one of the most common bacteria on the surface of human skin, strains found in hospitals tend to be particularly virulent.

UTIs are usually associated with congenital abnormalities of the urinary tract.[4][5][6] The term vesicoureteral [ureterovesical] reflux refers to backflow of urine from the bladder to the ureters or kidneys. Ureteropelvic obstruction is a blockage or narrowing of part of the urinary tract. These kinds of congenital abnormalities are known to be the root cause of most UTI, as they may allow pathogens to flow upstream within the urinary tract.

UTIs in Boys

In infant boys, UTIs originate from the external environment, strongly suggesting that these infections are iatrogenically caused.[7] Two interventions that put the male infant at immediate risk for UTIs are circumcision, and forced retraction of the foreskin. These interventions tear away the synechia which binds the foreskin to the glans in male infants, thereby creating entry points for E. coli bacteria,[8] which binds to the glans penis of the infant.[9] Urinary tract infections (UTI) are a complication of circumcision.[10][11][12][13]

Treatment

The most common way of relieving a urinary tract infection is the administration of anti-biotics,[1] if the infection does not clear up on its own.

Recurrent UTI

Recurrent UTIs are associated with congenital abnormalities of the upper urinary tract.[14][15][16][17][18] McCracken recommends investigation with radiographic and/or sonography.[19]

A recent study of mice indicates that p-fimbriated Escherichia Coli, the organism responsible for about 85% of UTI, is capable of burrowing into the deeper tissue of the bladder[20] or forming pods,[21] thus hiding from antibiotics.[22] Recurrent infections may actually be recurrence of the original infection, rather than a new infection ascending from the external genitals.

UTI and Renal Failure

In the past it was claimed that UTI could lead to renal failure, however, new evidence has disproved this claim.[23][24]

Prevention

Studies show fairly conclusively that UTIs can be easily prevented. Hospital-borne strains of E. coli remain the cause of the majority of UTIs, and infection can be resisted by taking certain measures to enhance the immunity of the infant to such pathogens.

Breastfeeding

It was determined in the 1990s that breastfeeding plays a central role substantially reducing the incidence of UTIs.[25][26][27][28][29][30][31] Outerbridge points out that breastfeeding is very effective in reducing incidence of UTI in both boys and girls.[32]

Rooming in

Rooming-in permits colonization of the infant's skin and mucosa with the mother's own bacteria. The prepuce and other skin and mucosa of the infant should be specifically brought into contact with the mother's own skin to pass along her flora and initiate the child's natural immunity.[33][34]

Non-intervention

Doctors and parents should refrain from touching a child's genitals as much as possible, as this could introduce E. coli into the urinary tract. When changing a child's diaper/nappy, parents should make sure their hands are sanitized, and be careful not to touch the area near the meatus (urinary opening) in either boys or girls. The insertion of parents' fingers into the foreskin, or even the handling of a baby's penis, could introduce bacteria into the preputial space of intact infants.

Parents should be careful not to forcibly retract the foreskin of a baby's penis, and to instruct the child's doctor and/or caretaker likewise. The act of forced retraction involves forcible separation that destroys a structural defense mechanism; the synechia which binds the foreskin to the glans is torn away, which allows E. coli to invade where it could not before.[35]

As circumcision necessitates forced retraction of the foreskin, additionally creating an open wound that is vulnerable to additional infection, parents are advised against circumcision. Recently, Fleiss et al. reviewed the immunological functions of the prepuce.[36] These functions suggest that the intact prepuce may offer protection against UTI if undisturbed. The foreskin provides two physical lines of defense in the intact male child, which are removed in circumcision: the preputial sphincter, which closes when a boy is not urinating, and a protected meatus (urinary opening), which is often inflamed and open in circumcised boys.[37] In addition, the sub-preputial moisture contains lysosyme, which has an anti-bacterial action.[38] Oligosaccharides excreted in the urine of breastfed babies prevent adhesion of pathogens to uroepithelial tissue.[39]

American Academy of Pediatrics Policy Changes

The American Academy of Pediatrics (AAP) has issued two statements which, when read together, constitute a substantial change in AAP policy toward the prevention of UTI in infants. First, in 1997, the AAP Workgroup on Breastfeeding recommended breastfeeding as highly beneficial in preventing a wide range of infections including UTI.[40] Second, in 1999, The 1999 AAP Task Force on Circumcision abandoned the previous stance of the 1989 Task Force on Circumcision that circumcision may provide protection against UTI.[41] The 1999 Task Force found that the bulk of the UTI studies were so methodologically flawed—by failing to control for confounding factors-such as breastfeeding—that no meaningful conclusions could be drawn from them. The 1999 AAP Task Force on Circumcision could not, therefore, recommend circumcision to reduce incidence of UTI (or any other disease).[42]

The 1999 AAP Task Force on Circumcision did, however, declare that breastfeeding produces a three fold reduction in UTI in infants. Two separate panels of the AAP, the Work Group on Breastfeeding and the 1999 Task Force on Circumcision, now recommend breastfeeding to reduce incidence of UTI.[43][44]

The UTI Scare

Drs. Charles Ginsburg and George McCracken carried out a study of UTI in boys at Parkland Hospital, a public hospital for indigent patients in Dallas, Texas. They reported that 95% of the boys in their study were not circumcised [45], and this piqued the interest of US Army pediatrician Thomas E. Wiswell.

In a determined search for an association between the presence of the foreskin and UTI, Wiswell et al retrospectively examined charts of a number of boys born at U.S. military hospitals.[46][47][48][49][50][51][52] Based on their observations of these old charts, they reported that Intact boys had a slightly higher rate of bacteriuria (bacteria in the urine) than circumcised boys during their first year of life, leading to the sensational statistic that circumcision resulted in a "ten to hundred times decrease in urinary tract infections in circumcised boys."

Wiswell's findings generated a great deal of controversy at the time. The prepuce (foreskin) is a protective organ, and one would not normally expect the removal of a healthy organ to reduce the risk of infections.[53] Nevertheless, the apparent correlation of intact foreskin to bacteriuria (and hence UTI) prompted the American Academy of Pediatrics (AAP) to review the evidence available in 1989.

Confounding Factors to Wiswell's Work

The problem began with Ginsburg and McCracken's study, which failed to notice that Parkland Hospital had made it hospital policy not to perform non-therapeutic circumcisions in neonates,[54] so the majority of its young male client population would have necessarily remained intact. The observation that 95% of the boys were not circumcised, therefore, indicated nothing more than that the majority of male infant patients at Parkland Hospital were not circumcised.

Wiswell's retrospective reviews of old hospital records failed to take a few factors into account:

  • The parents of some of the intact infants may have been instructed to forcibly retract the foreskin and scrub beneath, which would have put the children at a higher risk of infection. The same criticism applies to the later Wiswell studies and other American studies of infant UTI [Herzog, Roscelli] to date: None have taken care to ensure that there was a control group of infants whose foreskins were simply left alone.
  • Littlewood (1972) found an association of UTI with maternal infection, perinatal anoxia, and high or low birthweight.[55] Wiswell failed to account for these confounding factors, although they should have been known to him.
  • The Wiswell studies considered bacteriuria as diagnostic of UTI. However, a positive urine culture alone is not necessarily indicative of symptomatic UTI requiring treatment.[56] There is a significant false-positive rate in diagnosing UTI when urine cultures alone are used.[57][58] This criticism was addressed to some extent in Wiswell's second review.[59]
  • The hospital chart data used in the retrospective studies are unreliable. Hospitals frequently omit to record a circumcision on a baby's chart. In Atlanta, O'Brien found that circumcision was recorded only 84.3% of the time for circumcised boys.[60] If the records used in the retrospective bacteriuria studies are similarly inaccurate, then a statistically significant number of the infants with bacteriuria that were claimed to be intact were, in fact, circumcised. This would naturally overstate the rate of infection in intact boys.[61]
  • It is very possible that the use of surgical antiseptic (to kill pathogenic organisms during the circumcision procedure itself) was in part responsible for the slight reduction in bacteriuria observed in these studies. This possibility was not accounted for in the studies.
  • No information on rooming-in or breastfeeding history for the infants before they were hospitalized was recorded. Breastfeeding and rooming-in are important factors in the prevention of UTI.[62] (See above.)
  • Breastfeeding is a major confounding factor in any study of the role of circumcision in UTI. The Wiswell studies and all other studies in the literature fail to control for the effects of breastfeeding. The AAP observes that "breastfeeding status has not been evaluated systematically in studies assessing UTI and circumcision status."[63]

Even if...

Wiswell's sensational statistic, that circumcision resulted in a "ten to hundred times decrease in urinary tract infections in circumcised boys," has often been quoted; however, it is misleading. In fact, UTIs are so rare in either case that,even giving Wiswell's data the benefit of the doubt, 50 to 100 healthy boys would have to be circumcised in order to prevent a UTI from developing in only one patient. Using more recent data from a better-controlled study, the number of unnecessary operations needed to prevent one hospital admission for UTI would jump to 195.[64]

Later Studies

A number of studies in post-circumcision UTIs, and the role of the surgery in possibly facilitating UTIs, were not able to recommend neonatal circumcision.[65][66][67][68] Significantly, a number of recent Israeli studies have reported an increase in urinary tract infection rates in the period following ritual circumcision.[69][70][71][72] In a prospective study, Kayaba et al. found a zero incidence of UTI in 603 intact boys, over a range of ages.[73] Although this study did not focus on UTI, the Japanese researchers concluded: "Awareness of these findings will eliminate unnecessary circumcision in boys."

The AAP Lays the UTI/Circumcision Myth to Rest

In their 1989 report, the AAP acknowledeged that "these studies in army hospitals are retrospective in design and may have methodologic flaws. For example, they do not include all boys born in any single cohort or those treated as outpatients, so the study population may have been influenced by selection bias." Furthermore, the babies in the studies were all hospitalized due to sickness, and so do not represent infants in the general population.

Conclusion

The notion that circumcision is a useful prophylactic against UTI has been laid to rest by the 1999 AAP Task Force on Circumcision.[74] Instead, healthy, natural alternatives such as breastfeeding and rooming-in must be given favor. Breastfeeding offers a wide range of benefits for both mother and baby. Circumcision is surgery, and as such it has attendant risks, which include UTI itself.

References

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