Pregnant women with urinary group B streptococcal infection should be treated and should receive intrapartum prophylactic therapy. Urinary tract infections UTIs are frequently encountered in the family physician's office. UTIs account for approximately 10 percent of office visits by women, and 15 percent of women will have a UTI at some time during their life.
In pregnant women, the incidence of UTI can be as high as 8 percent. We review the diagnosis and treatment of asymptomatic bacteriuria, acute cystitis and pyelonephritis, plus the unique issues of group B streptococcus and recurrent infections. Pregnant women are at increased risk for UTIs. Beginning in week 6 and peaking during weeks 22 to 24, approximately 90 percent of pregnant women develop ureteral dilatation, which will remain until delivery hydronephrosis of pregnancy.
Increased bladder volume and decreased bladder tone, along with decreased ureteral tone, contribute to increased urinary stasis and ureterovesical reflux. Up to 70 percent of pregnant women develop glycosuria, which encourages bacterial growth in the urine. Increases in urinary progestins and estrogens may lead to a decreased ability of the lower urinary tract to resist invading bacteria. This decreased ability may be caused by decreased ureteral tone or possibly by allowing some strains of bacteria to selectively grow.
The organisms that cause UTIs during pregnancy are the same as those found in nonpregnant patients. Escherichia coli accounts for 80 to 90 percent of infections. Other gram-negative rods such as Proteus mirabilis and Klebsiella pneumoniae are also common. Gram-positive organisms such as group B streptococcus and Staphylococcus saprophyticus are less common causes of UTI. Group B streptococcus has important implications in the management of pregnancy and will be discussed further.
Less common organisms that may cause UTI include enterococci, Gardnerella vaginalis and Ureaplasma ureolyticum. UTIs have three principle presentations: asymptomatic bacteriuria, acute cystitis and pyelonephritis. The diagnosis and treatment of UTI depends on the presentation. In the s, Kass 6 noted the subsequent increased risk of developing pyelonephritis in patients with asymptomatic bacteriuria.
Significant bacteriuria has been historically defined as finding more than 10 5 colony-forming units per mL of urine. This has not been studied in pregnant women, and finding more than 10 5 colony-forming units per mL of urine remains the commonly accepted standard.
Asymptomatic bacteriuria is common, with a prevalence of 10 percent during pregnancy. Untreated asymptomatic bacteriuria leads to the development of symptomatic cystitis in approximately 30 percent of patients and can lead to the development of pyelonephritis in up to 50 percent. The American College of Obstetrics and Gynecology recommends that a urine culture be obtained at the first prenatal visit. By screening for and aggressively treating pregnant women with asymptomatic bacteriuria, it is possible to significantly decrease the annual incidence of pyelonephritis during pregnancy.
Rouse and colleagues 14 performed a cost-benefit analysis of screening for bacteriuria in pregnant women versus inpatient treatment of pyelonephritis and found a substantial decrease in overall cost with screening. Wadland and Plante 15 performed a similar analysis in a family practice obstetric population and found screening for asymptomatic bacteriuria to be cost-effective.
The decision about how to screen asymptomatic women for bacteriuria is a balance between the cost of screening versus the sensitivity and specificity of each test. The gold standard for detection of bacteriuria is urine culture, but this test is costly and takes 24 to 48 hours to obtain results.
The accuracy of faster screening methods e. Bachman and associates 16 compared these screening methods with urine culture and found that while it was more cost effective to screen for bacteriuria with the esterase dipstick for leukocytes, only one half of the patients with bacteriuria were identified compared with screening by urine culture.
The increased number of false negatives and the relatively poor predictive value of a positive test make the faster methods less useful; therefore, a urine culture should be routinely obtained in pregnant women to screen for bacteriuria at the first prenatal visit and during the third trimester.
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Pregnant women should be treated when bacteriuria is identified Table 2 17 , The choice of antibiotic should address the most common infecting organisms i. The antibiotic should also be safe for the mother and fetus. Historically, ampicillin has been the drug of choice, but in recent years E. Alternatively, cephalosporins are well tolerated and adequately treat the important organisms.
Fosfomycin Monurol is a new antibiotic that is taken as a single dose. Sulfonamides can be taken during the first and second trimesters but, during the third trimester, the use of sulfonamides carries a risk that the infant will develop kernicterus, especially preterm infants. Other common antibiotics e. Information from Duff P.
Antibiotic selection for infections in obstetric patients. Semin Perinatol ;—78, and Krieger JN. Complications and treatment of urinary tract infections during pregnancy. Urol Clin North Am ;— A seven- to day course of antibiotic treatment is usually sufficient to eradicate the infecting organism s. Some authorities have advocated shorter courses of treatment—even single-day therapy.
Conflicting evidence remains as to whether pregnant patients should be treated with shorter courses of antibiotics. Masterton 21 demonstrated a cure rate of 88 percent with a single 3-g dose of ampicillin in ampicillin-sensitive isolates. Several other studies have found that a single dose of amoxicillin, cephalexin Keflex or nitrofurantoin was less successful in eradicating bacteriuria, with cure rates from 50 to 78 percent.
Other antibiotics have not been extensively researched for use in UTIs, and further studies are necessary to determine whether a shorter course of other antibiotics would be as effective as the traditional treatment length. Acute cystitis is distinguished from asymptomatic bacteriuria by the presence of symptoms such as dysuria, urgency and frequency in afebrile patients with no evidence of systemic illness.
Up to 30 percent of patients with untreated asymptomatic bacteriuria later develop symptomatic cystitis. In general, treatment of pregnant patients with acute cystitis is initiated before the results of the culture are available. Antibiotic choice, as in asymptomatic bacteriuria, should focus on coverage of the common pathogens and can be changed after the organism is identified and sensitivities are determined. A three-day treatment course in nonpregnant patients with acute cystitis has a cure rate similar to a treatment course of seven to 10 days, but this finding has not been studied in the obstetric population.
In the pregnant patient, this higher rate of recurrence with shorter treatment periods may have serious consequences. Table 2 17 , 18 lists oral antibiotics that are acceptable treatment choices. Group B streptococcus is generally susceptible to penicillin, but E. Acute pyelonephritis during pregnancy is a serious systemic illness that can progress to maternal sepsis, preterm labor and premature delivery. The diagnosis is made when the presence of bacteriuria is accompanied by systemic symptoms or signs such as fever, chills, nausea, vomiting and flank pain.
Symptoms of lower tract infection i. Pyelonephritis occurs in 2 percent of pregnant women; up to 23 percent of these women have a recurrence during the same pregnancy. Early, aggressive treatment is important in preventing complications from pyelonephritis. Hospitalization, although often indicated, is not always necessary.
However, hospitalization is indicated for patients who are exhibiting signs of sepsis, who are vomiting and unable to stay hydrated, and who are having contractions. A randomized study of 90 obstetric inpatients with pyelonephritis compared treatment with oral cephalexin to treatment with intravenous cephalothin Keflin and found no difference between the two groups in the success of therapy, infant birth weight or preterm deliveries. Further support for outpatient therapy is provided in a randomized clinical trial that compared standard inpatient, intravenous treatment to outpatient treatment with intramuscular ceftriaxone Rocephin plus oral cephalexin.
Most cases are thought to occur when bacteria that live harmlessly in the bowel or on the skin get into the bladder through the tube that carries urine out of your body urethra. Women may get cystitis more often than men because their bottom anus is closer to their urethra and their urethra is much shorter, which means bacteria may be able to get into the bladder more easily.
If you have been having mild symptoms for less than 3 days or you have had cystitis before and do not feel you need to see a GP, you may want to treat your symptoms at home or ask a pharmacist for advice. Some people believe that cranberry drinks and products that reduce the acidity of their urine such as sodium bicarbonate or potassium citrate will help.
If you see a GP and they diagnose you with cystitis, you'll usually be prescribed a course of antibiotics to treat the infection. If you keep getting cystitis, a GP may give you an antibiotic prescription to take to a pharmacy whenever you develop symptoms, without needing to see a doctor first. Your GP can also prescribe a low dose of antibiotics for you to take continuously over several months.
If you get cystitis frequently, there are some things you can try that may stop it coming back. Drinking cranberry juice has traditionally been recommended as a way of reducing your chances of getting cystitis. But large studies have suggested it does not make a significant difference. If you have long-term or frequent pelvic pain and problems peeing, you may have a condition called interstitial cystitis. This is a poorly understood bladder condition that mostly affects middle-aged women.
Unlike regular cystitis, there's no obvious infection in the bladder and antibiotics do not help. Books on fertility awareness can be helpful and ovulation prediction kits are widely available at pharmacies. There are also many ways to decrease pain and increase your enjoyment of sex.
Some IC patients prefer minimal prenatal testing and a low-intervention birth, while others may feel more comfortable with a more highly managed pregnancy and birth.
This decision is a matter of personal choice and an important factor to consider when you are making your plan. Communication among the members of your healthcare team is especially important. Make it a point to ensure that all of your doctors and other healthcare providers are in touch with each other. If your health insurance plan offers limited choice in prenatal care providers, you may need to educate your assigned providers about IC and pelvic pain.
Today, many doctors advise women to discontinue all but the safest medicines during pregnancy, especially during the first trimester. Some IC patients can control their symptoms with nondrug approaches such as diet, other self-help techniques, and physical therapy. Others may be able to use medicines that have minimal effects throughout the body, such as nonalkalinized anesthetic bladder instillations or topical medications.
But some patients need to continue stronger medicines. If your doctors are not comfortable managing these medicines during your pregnancy, consider working with a perinatologist.
Perinatology is a subspecialty of obstetrics focused on high-risk pregnancies. An important part of this practice is caring for pregnant women who have special medical risks and challenges.
Perinatologists are trained in managing riskier medications and treatments during pregnancy. A perinatologist and your OB or primary care doctor may work together, with the perinatologist consulting as needed or regularly, or you and your doctors may decide to have the perinatologist take over your obstetric care.
Numerous studies indicate that proper nutrition is vital both before and during pregnancy. If you have not already done so, try to identify foods, beverages, and supplements that are irritating to your bladder before you conceive so you can eat a healthy, balanced diet and take the prenatal supplements you and your developing baby need. If multivitamins bother your IC, consider taking these essential nutrients as individual supplements.
Folate is critical, and diet cannot supply enough, so if folate is bothersome, try taking no more than the recommended amount, testing different brands, and splitting up the dose over the day.
Iron may be constipating, but some forms may be less so. Vegetarians also need to take B12 because only animal products contain it.
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