Urinary Tract Infections in Pregnancy Treatment & Management
- Author: Emilie Katherine Johnson, MD, MPH; Chief Editor: Edward David Kim, MD, FACS more...
Treatment of bacteriuria and cystitis
Because of the dangers of maternal and fetal complications, acute care (eg, in the emergency department [ED]) should focus on identifying and treating asymptomatic and symptomatic bacteriuria, along with ensuring that an alternate process is not the cause of the symptoms.
Treatment of asymptomatic bacteriuria in pregnant patients is important because of the increased risk of urinary tract infection (UTI) and its associated sequelae. ED care may involve the following:
Administration of appropriate antibiotics
Administration of fluid if the patient is dehydrated
Admission if any indication of complicated UTI exists
Any discussion of treatment should be prefaced with a discussion of behavioral methods that may be used to ensure good hygiene and reduce bacterial contamination of the urethral meatus, thereby preventing inadequate treatment and recurrent infection. Behavioral methods include the following:
Wipe front-to-back after urinating or defecating
Wash hands before using the toilet
Use washcloths to clean the perineum
Use liquid soap to prevent colonization from bar soap
Clean the urethral meatus first when bathing
Oral antibiotics are the treatment of choice for asymptomatic bacteriuria and cystitis. Appropriate oral regimens include the following:
Cephalexin 500 mg 4 times daily
Ampicillin 500 mg 4 times daily
Nitrofurantoin 100 mg twice daily
Sulfisoxazole 1 g 4 times daily
The resistance of Escherichia coli to ampicillin and amoxicillin is 20-40%; accordingly, these agents are no longer considered optimal for treatment of UTIs caused by this organism. Fosfomycin, a phosphonic acid derivative, is useful in the treatment of uncomplicated UTIs caused by susceptible strains of E coli and Enterococcus species. Fosfomycin is a US Food and Drug Administration (FDA) category B agent in pregnancy (ie, animal studies have not demonstrated a risk to the fetus and there are no adequate and well-controlled studies in pregnant women).
Although 1-, 3-, and 7-day antibiotic courses have been evaluated, 10-14 days of treatment is usually recommended to eradicate the offending bacteria. For example, studies with cephalexin, trimethoprim-sulfamethoxazole, and amoxicillin have indicated that a single dose is as effective as a 3- to 7-day course of therapy, but the cure rate is only 70%. The data are insufficient to justify abandoning the more traditional long-term regimens, even in the case of asymptomatic bacteriuria.
Treatment success depends on eradication of the bacteria rather than on the duration of therapy. A test-for-cure urine culture should show negative findings 1-2 weeks after therapy. A nonnegative culture result is an indication for a 10- to 14-day course of a different antibiotic, followed by suppressive therapy (eg, nitrofurantoin 50 mg at bedtime) until 6 weeks postpartum.
Mathai et al suggest the need for disseminated guidelines for practitioners in developing countries such as India. Their study documented inappropriate use of antibiotics in terms of safety, cost, susceptibility, and threat for developing resistance.
Treatment of pyelonephritis
The standard course of treatment for pyelonephritis consists of hospital admission and intravenous (IV) administration of cephalosporins or gentamicin. IV fluids must be administered with caution. Patients with pyelonephritis can become dehydrated because of nausea and vomiting and need IV hydration. However, they are at high risk for the development of pulmonary edema and acute respiratory distress syndrome (ARDS).
Fever should be managed with antipyretics (preferably, acetaminophen) and nausea and vomiting with antiemetics. Most antiemetics can be used for adverse effects caused by antibiotics, but doxylamine, Emetrol (Wellspring, Sarasota, FL; pregnancy class A), dimenhydrinate, and metoclopramide (pregnancy class B) are preferred.
Preterm labor and delivery are additional risks associated with pyelonephritis. These risks must be evaluated and treated early in the course of admission.
In a randomized, controlled trial of outpatient treatment of pyelonephritis in pregnancy, Millar et al concluded that outpatient therapy is as safe and effective as inpatient care in the treatment of pyelonephritis before 24 weeks’ gestation. However, the prevailing view is still that aggressive inpatient hydration and parenteral antibiotics are necessary. Pyelonephritis places the patient at risk for spontaneous abortion in early pregnancy and for preterm labor after 24 weeks’ gestation.
In their study, Millar et al treated outpatients with 2 doses of intramuscular (IM) ceftriaxone and 10 days of oral cephalexin. Initial outpatient therapy and traditional inpatient therapy failed to cure equal numbers of patients. Benefits include the obvious cost savings and the psychosocial benefits for the patient. Risks include septic shock and respiratory insufficiency at home during outpatient therapy.
Strict guidelines for an observation period before ED discharge, patient education, and home nursing have been discussed. In addition, approximately two thirds of the outpatient treatment group did not complete the study because the subjects developed 1 or more complications. If outpatient therapy is considered, only selected patients in their second trimester should be considered. More study is necessary before a change in the physician’s practice pattern is considered.
Antibiotic selection should be based on urine culture sensitivities, if known. Often, therapy must be initiated on an empirical basis, before culture results are available. This requires clinical knowledge of the most common organisms and their practice-specific or hospital-specific sensitivities to medications.
Institution-specific drug resistances should also be considered before a treatment antibiotic is chosen. For instance, with E coli infection alone, resistance to ampicillin can be as high as 28-39%. Resistance to trimethoprim-sulfamethoxazole has been described as 31%, and resistance to first-generation cephalosporins may be as high as 9-19%.
Maternal physiologic changes that influence pharmacokinetics include increased glomerular filtration rate (GFR) and renal plasma flow, increased volume of distribution, decreased gastric motility and emptying, and decreased albumin levels. Serum levels of antibiotics are lower in pregnancy because of the gross increase in blood volume and the increased GFR.
Some antibiotics should not be used during pregnancy, because of their effects on the fetus. These include the following:
Tetracyclines (adverse effects on fetal teeth and bones and congenital defects)
Trimethoprim in the first trimester (facial defects and cardiac abnormalities)
Chloramphenicol (gray syndrome)
Sulfonamides in the third trimester (hemolytic anemia in mothers with glucose-6-phosphate dehydrogenase [G6PD] deficiency, jaundice, and kernicterus)
Fluoroquinolones are to be used with caution in pregnancy. Both ciprofloxacin and levofloxacin have been assigned pregnancy category C by the FDA (fetal risk is not confirmed by human studies but has been shown in some animal studies). Although not a first-line option for treatment of UTI in pregnancy, in certain clinical situations the benefits of using a fluoroquinolone may outweigh the risks to the developing fetus.
Risks to the mother from fluoroquinolones must also be considered. In May 2016 the FDA advised that the risks of fluoroquinolones generally outweigh the benefits for patients with uncomplicated infections, including UTIs, and recommended reserving fluoroquinolones for patients who do not have alternative treatment options. Disabling and potentially permanent serious adverse effects associated with fluoroquinolones have involved tendons, muscles, joints, nerves, and the central nervous system.
Nitrofurantoin is safe and effective; however, poor tissue penetration has limited its use in pyelonephritis. In the past, nitrofurantoin was completely avoided in the third trimester because of hemolytic effects on the newborn. Currently, restriction of this agent is limited to the last several weeks of pregnancy. Use during this period can cause hemolytic anemia in the fetus or neonate as a consequence of their immature erythrocyte enzyme systems (glutathione instability). Nitrofurantoin is also safe and effective for once-daily prophylactic therapy during pregnancy.
Macrolides are not first-line agents for UTI in pregnancy. However, they are well tolerated by mother and fetus. A meta-analysis concluded that although antibiotic treatment is effective in patients with UTIs, the data are insufficient to recommend any specific regimen for treatment of symptomatic UTIs during pregnancy.[25, 26] All of the antibiotics studied were effective in terms of both increasing cure rates of UTI in pregnancy and decreasing the incidence of associated adverse outcomes. Current regimens are summarized in Table 1 below.
Table. Treatment Regimens for Pregnant Women with UTI (Open Table in a new window)
Surgical care is rarely indicated, unless one of the pathologic causes listed in the differential diagnoses is suspected.
In patients with urethral or bladder diverticulum, bladder stones, urethral syndrome, lower urinary tract trauma, interstitial cystitis, or bladder cancer, cystoscopy may aid in establishing the diagnosis.
A retrograde stent or a percutaneous nephrostomy tube should be placed to relieve ureteral colic or decompress an obstructed infected collecting system. More invasive procedures, such as ureteroscopic stone extraction, are rarely indicated. Extracorporeal shock wave lithotripsy (ESWL) is contraindicated in pregnancy.
In the rare patient for whom invasive surgical therapy is indicated, the operation should be planned for the second trimester. Surgical intervention during the first trimester is associated with miscarriage; surgery in the third trimester is associated with preterm labor. Urgent surgical intervention in the third trimester should coincide with delivery of the fetus.
[Guideline] Nicolle LE, Bradley S, Colgan R, Rice JC, Schaeffer A, Hooton TM. Infectious Diseases Society of America guidelines for the diagnosis and treatment of asymptomatic bacteriuria in adults. Clin Infect Dis. 2005 Mar 1. 40(5):643-54. [Medline].
Minassian C, Thomas SL, Williams DJ, Campbell O, Smeeth L. Acute maternal infection and risk of pre-eclampsia: a population-based case-control study. PLoS One. 2013 Sep 3. 8(9):e73047. [Medline]. [Full Text].
McKenzie H, Donnet ML, Howie PW, Patel NB, Benvie DT. Risk of preterm delivery in pregnant women with group B streptococcal urinary infections or urinary antibodies to group B streptococcal and E. coli antigens. Br J Obstet Gynaecol. 1994 Feb. 101(2):107-13. [Medline].
[Guideline] American Academy of Pediatrics and American College of Obstetricians and Gynecology. Guidelines for Perinatal Care. American Academy of Pediatrics. 2007. 6th ed:
Smaill F. Asymptomatic bacteriuria in pregnancy. Best Pract Res Clin Obstet Gynaecol. 2007 Jun. 21(3):439-50. [Medline].
Alvarez JR, Fechner AJ, Williams SF, Ganesh VL, Apuzzio JJ. Asymptomatic bacteriuria in pregestational diabetic pregnancies and the role of group B streptococcus. Am J Perinatol. 2010 Mar. 27(3):231-4. [Medline].
Hollowell JG. Outcome of pregnancy in women with a history of vesico-ureteric reflux. BJU Int. 2008 Sep. 102(7):780-4. [Medline].
Ghafari A, Sanadgol H. Pregnancy after renal transplantation: ten-year single-center experience. Transplant Proc. 2008 Jan-Feb. 40(1):251-2. [Medline].
Versi E, Chia P, Griffiths DJ, Harlow BL. Bacteriuria in pregnancy: a comparison of Bangladeshi and Caucasian women. Int Urogynecol J Pelvic Floor Dysfunct. 1997. 8(1):8-12. [Medline].
Mazor-Dray E, Levy A, Schlaeffer F, Sheiner E. Maternal urinary tract infection: is it independently associated with adverse pregnancy outcome?. J Matern Fetal Neonatal Med. 2009 Feb. 22(2):124-8. [Medline].
Sheiner E, Mazor-Drey E, Levy A. Asymptomatic bacteriuria during pregnancy. J Matern Fetal Neonatal Med. 2009 May. 22(5):423-7. [Medline].
Whitehead NS, Callaghan W, Johnson C, Williams L. Racial, ethnic, and economic disparities in the prevalence of pregnancy complications. Matern Child Health J. 2009 Mar. 13(2):198-205. [Medline].
Hill JB, Sheffield JS, McIntire DD, Wendel GD Jr. Acute pyelonephritis in pregnancy. Obstet Gynecol. 2005 Jan. 105(1):18-23. [Medline].
Collier CH, Risnes K, Norwitz ER, Bracken MB, Illuzzi JL. Maternal infection in pregnancy and risk of asthma in offspring. Matern Child Health J. 2013 Dec. 17(10):1940-50. [Medline].
Easter SR, Cantonwine DE, Zera CA, Lim KH, Parry SI, McElrath TF. Urinary tract infection during pregnancy, angiogenic factor profiles, and risk of preeclampsia. Am J Obstet Gynecol. 2016 Mar. 214 (3):387.e1-7. [Medline].
[Guideline] U.S. Preventive Services Task Force. Screening for asymptomatic bacteriuria in adults: U.S. Preventive Services Task Force reaffirmation recommendation statement. Ann Intern Med. 2008 Jul 1. 149(1):43-7. [Medline].
Duarte G, Marcolin AC, Quintana SM, Cavalli RC. [Urinary tract infection in pregnancy]. Rev Bras Ginecol Obstet. 2008 Feb. 30(2):93-100. [Medline].
Millar LK, Cox SM. Urinary tract infections complicating pregnancy. Infect Dis Clin North Am. 1997 Mar. 11(1):13-26. [Medline].
Kodikara H, Seneviratne H, Kaluarachchi A, Corea E. Diagnostic accuracy of nitrite dipstick testing for the detection of bacteriuria of pregnancy. Public Health. 2009 May. 123(5):393-4. [Medline].
Gilstrap LC 3rd, Ramin SM. Urinary tract infections during pregnancy. Obstet Gynecol Clin North Am. 2001 Sep. 28(3):581-91. [Medline].
Widmer M, Gülmezoglu AM, Mignini L, Roganti A. Duration of treatment for asymptomatic bacteriuria during pregnancy. Cochrane Database Syst Rev. 2011. (12):CD000491. [Medline].
Mathai E, Thomas RJ, Chandy S, Mathai M, Bergstrom S. Antimicrobials for the treatment of urinary tract infection in pregnancy: practices in southern India. Pharmacoepidemiol Drug Saf. 2004 Sep. 13(9):645-52. [Medline].
Millar LK, Wing DA, Paul RH, Grimes DA. Outpatient treatment of pyelonephritis in pregnancy: a randomized controlled trial. Obstet Gynecol. 1995 Oct. 86(4 Pt 1):560-4. [Medline].
FDA Drug Safety Communication: FDA advises restricting fluoroquinolone antibiotic use for certain uncomplicated infections; warns about disabling side effects that can occur together. U.S. Food and Drug Administration. Available at http://www.fda.gov/drugs/drugsafety/ucm500143.htm. May 12, 2016; Accessed: July 21, 2016.
Vazquez JC, Abalos E. Treatments for symptomatic urinary tract infections during pregnancy. Cochrane Database Syst Rev. 2011 Jan 19. CD002256. [Medline].
Widmer M, Gülmezoglu AM, Mignini L, Roganti A. Duration of treatment for asymptomatic bacteriuria during pregnancy. Cochrane Database Syst Rev. 2011 Dec 7. 12:CD000491. [Medline].
Bozkurt Y, Penbegul N, Soylemez H, Atar M, Sancaktutar AA, Yildirim K, et al. The efficacy and safety of ureteroscopy for ureteral calculi in pregnancy: our experience in 32 patients. Urol Res. 2012 Jan 4. [Medline].
Lichtenberger P, Hooton TM. Antimicrobial prophylaxis in women with recurrent urinary tract infections. Int J Antimicrob Agents. 2011 Dec. 38 Suppl:36-41. [Medline].
ACOG. ACOG educational bulletin. Antibiotics and gynecologic infections. American College of Obstetricians and Gynecologists. Number 237, June 1997 (Replaces No. 153, March 1991). Int J Gynaecol Obstet. 1997 Sep. 58(3):333-40. [Medline].
Rouse DJ, Andrews WW, Goldenberg RL, Owen J. Screening and treatment of asymptomatic bacteriuria of pregnancy to prevent pyelonephritis: a cost-effectiveness and cost-benefit analysis. Obstet Gynecol. 1995 Jul. 86(1):119-23. [Medline].
Thurman AR, Steed LL, Hulsey T, Soper DE. Bacteriuria in pregnant women with sickle cell trait. Am J Obstet Gynecol. 2006 May. 194(5):1366-70. [Medline].
Kazemier BM, Schneeberger C, De Miranda E, Van Wassenaer A, Bossuyt PM, Vogelvang TE. Costs and effects of screening and treating low risk women with a singleton pregnancy for asymptomatic bacteriuria, the ASB study. BMC Pregnancy Childbirth. 2012. 12:52. [Medline].
Wing DA, Rumney PJ, Preslicka CW, Chung JH. Daily cranberry juice for the prevention of asymptomatic bacteriuria in pregnancy: a randomized, controlled pilot study. J Urol. 2008 Oct. 180(4):1367-72. [Medline]. [Full Text].
Uehling DT, Hopkins WJ, Elkahwaji JE, Schmidt DM, Leverson GE. Phase 2 clinical trial of a vaginal mucosal vaccine for urinary tract infections. J Urol. 2003 Sep. 170(3):867-9. [Medline].
Mann JR, McDermott S. Are Maternal Genitourinary Infection and Pre-Eclampsia Associated With ADHD in School Aged Children?. J Atten Disord. 2010 Sep 13. [Medline].
Sun Y, Vestergaard M, Christensen J, Nahmias AJ, Olsen J. Prenatal exposure to maternal infections and epilepsy in childhood: a population-based cohort study. Pediatrics. 2008 May. 121(5):e1100-7. [Medline].