UTIs In PregnancyShreya Susan Koshy

INTRODUCTION

 By convention, UTI is defined either as a lower tract (acute cystitis) or upper tract (acute pyelonephritis) infection

UTI may be asymptomatic (subclinical infection) or symptomatic (disease).

Thus, the term UTI encompasses a variety of clinical entities, including asymptomatic bacteriuria (ABU), cystitis, prostatitis, and pyelonephritis.

ABU occurs in the absence of symptoms attributable to the bacteria in the urinary tract and does not usually require treatment

UTI has more typically been assumed to imply symptomatic disease that warrants antimicrobial therapy.

IN PREGNANCY

These are the most common bacterial infections during pregnancy.

Asymptomatic bacteriuria is the most common

In pregnant women, ABU has clinical consequences, and both screening for and treatment of this condition are indicated

Specifically, ABU during pregnancy is associated with preterm birth and perinatal mortality for the fetus and with pyelonephritis for the mother.

ETIOLOGY

Normal perineal flora E.coli (75-90% of isolates), Klebsiella,

Proteus, Citrobacter, Enterococcus Complicated UTI – All the above, plus

Acinetobacter species, Morganella species, and Pseudomonas aeruginosa

ASYMPTOMATIC BACTERIURIA

The incidence during pregnancy is similar to that in nonpregnant women and varies from 2 to 7 percent

Recurrent bacteriuria is more common during pregnancy

 Typically occurs during early pregnancy, with only approximately a quarter of cases identified in the second and third trimesters

A clean-voided specimen containing more than 100,000 organisms/mL is diagnostic.

there have been instances of counts from 20,000- 50,000/ml resulting in pyelonephritis

SIGNIFICANCE

If not treated, approximately 25 percent of infected women will develop symptomatic infection during pregnancy.

In some, but not all studies, covert bacteriuria has been associated with preterm or low-birthweight infants

Schieve and coworkers (1994) reported urinary tract infection to be associated with increased risks for low-birthweight infants, preterm delivery, pregnancy associated hypertension, and anemia.

Screening And Treatment Performed at 12 to 16 weeks gestation (or the first

prenatal visit, if that occurs later) with a urine culture  Reasonable to rescreen women at high risk for

infection (eg, history of UTI or presence of urinary tract anomalies, diabetes mellitus, hemoglobin S, or preterm labor)

Specimen – Mid stream clean catch Diagnosis – one specimen growing organisms ≥105

Treatment - antibiotic therapy tailored to culture results and follow-up cultures to confirm sterilization of the urine. For those women with persistent or recurrent bacteriuria, prophylactic or suppressive antibiotics may be warranted in addition to retreatment

Oral Antimicrobial Agents Used for Treatment of Pregnant Women with Asymptomatic BacteriuriaSingle-dose treatmentAmoxicillin, 3 gAmpicillin, 2 gCephalosporin, 2 gNitrofurantoin, 200 mgTrimethoprim-sulfamethoxazole, 320/1600 mg3-day courseAmoxicillin, 500 mg three times dailyAmpicillin, 250 mg four times dailyCephalosporin, 250 mg four times dailyCiprofloxacin, 250 mg twice dailyLevofloxacin, 250 or 500 mg dailyNitrofurantoin, 50 to 100 mg four times daily or100 mg twice dailyTrimethoprim-sulfamethoxazole, 160/800 mg twotimes dailyOtherNitrofurantoin, 100 mg four times daily for 10 daysNitrofurantoin, 100 mg twice daily for 5 to 7 daysNitrofurantoin, 100 mg at bedtime for 10 daysTreatment failuresNitrofurantoin, 100 mg four times daily for 21 daysSuppression for bacterial persistence or recurrenceNitrofurantoin, 100 mg at bedtime for pregnancyremainder

ACUTE CYSTITIS CLINICAL MANIFESTATIONS  The typical symptoms of acute cystitis in the

pregnant woman are the same as in nonpregnant women

Include the sudden onset of dysuria and urinary urgency and frequency. Hematuria and pyuria are also frequently seen on urinalysis.

Systemic symptoms, such as fevers and chills, are generally absent in isolated cystitis

DIAGNOSIS AND TREATMENT Acute cystitis should be suspected in pregnant women who

complain about dysuria The presence of fever and chills, flank pain, and

costovertebral angle tenderness should raise suspicion for pyelonephritis

Urinanalysis, and culture Prior to confirming the diagnosis, empiric treatment is

typically initiated in a patient with consistent symptoms and pyuria on urinalysis

 it is reasonable to use a quantitative count ≥103 cfu/mL in a symptomatic pregnant woman as an indicator of symptomatic UTI

Treatment is by the same drugs used in treatment of asymptomatic bacteriuria

ACUTE PYELONEPHRITIS Fever (>38ºC or 100.4ºF), flank pain, nausea,

vomiting, and/or costovertebral angle tenderness Pyuria is a typical finding Most cases of pyelonephritis occur during the second

and third trimesters Pregnant women may become quite ill and are at risk for

both medical and obstetrical complications from pyelonephritis

 As many as 20 percent of women with severe pyelonephritis develop complications that include septic shock syndrome or its variants, such as acute respiratory distress syndrome 

DIAGNOSIS AND TREATMENT Clinical symptoms + urinanalysis and culture Low threshold for suspicion Pyuria seen in a majority  In patients with pyelonephritis who are severely ill or who also

have symptoms of renal colic or history of renal stones, diabetes, history of prior urologic surgery, immunosuppression, repeated episodes of pyelonephritis, or urosepsis, imaging of the kidneys can be helpful to evaluate for complications

 Hospital admission for parenteral antibiotics, that can later be converted to an oral regime following profiling of organism

 suppressive antibiotics are typically used for the remainder of the pregnancy to prevent recurrence.

 Parenteral, broad spectrum beta-lactams are the preferred antibiotics for initial empiric therapy of pyelonephritis

OBSTRETRIC MANAGEMENT

Pyelonephritis is not itself an indication for delivery

If induction of labor or c-section is planned then wait till patient is afebrile.

HIV IN PREGNANCY

EFFECT OF

Pregnancy on HIV Does not increase progression

of HIV to AIDS Opportunistic infections maybe

less aggressively investigated and treated due to concerns for fetus, causing maternal risk

HIV on pregnancyIncreased risk of Miscarriage Preeclampsia Preterm delivery IUGR Vertical transmission

DIAGNOSIS

Positive ELISA confirmed by western blot or IF assay Or two positive ELISAs CD4 count for immunosuppression degree Viral load for disease progression

VERTICAL TRANSMISSION

Antepartum 0-14 weeks 1%14-36 weeks 4%>36 12%

Intrapartum 8Postpartum with breast feeding

Established infection 14Primary infection 29

In India risk of vertical transmission is about 30%

FACTORS INCREASING VERTICAL TRANSMISSION

Disease Factors Viral load Seroconversion Advanced mutant disease Low CD4

Obstetric Factors Vaginal delivery Prolonged rupture of

membranes LBW Antepartum invasive procedure Breastfeeding

SCREENING All pregnant women should be offered screening

early in pregnancy Pretest and posttest counselling mandatory

ANTENATAL CAREOption of MTP should be discussed earliestHIV +ve mothers should be counselled about nutrition, hygiene, safe sex practices, etcDetailed anomaly scan should be a priorityProphylaxis for pneumocystis indicated when CD4 count is <200mm3

ANTI RETROVIRAL THERAPY RCOG GUIDELINES They recommend either zidovudine monotherapy or

HAART(advanced disease, high viral load or low CD4 count) WHO GUIDELINES Option A- Zidovudine twice daily 14 weeks onwards,

Neviparine single dose at labor onset, Zidovudine and lamivudine twice daily during labor and 1 week postpartum

OPTION B triple drug prophylaxis from 14 weeks and during breast feeding

NACO GUIDELINES Neviparine single dose 200mg onset of labor, single dose of

2mg/kg to neonate within three days of delivery

INTRAPARTUM MANAGEMENT When antiretroviral therapy was given in the prenatal,

intrapartum, and neonatal periods along with cesarean delivery, the likelihood of neonatal transmission was reduced by 87 percent compared with vaginal delivery and without antiretroviral therapy

Elective c section at 38 weeks for all women not taking HAART and viral load >50/ml is advised

Planned vaginal if on HAART and viral load less than 50/ml

In Zidovudine monotherapy c section reduces infection risk

Universal Precautions should be followed stringently

BREAST FEEDING The probability of HIV transmission per liter of

breast milk ingested is estimated to be similar in magnitude to heterosexual transmission with unsafe sex in adults

Most transmission occurs in the first 6 months, and as many as two thirds of infections in breast-fed infants are from breast milk.

In the Petra Study Team (2002) from Africa, the prophylactic benefits of shortcourse perinatal anti viral regimens were diminished considerably by 18 months of age due to breast feeding

POSTPARTUM MANAGEMENT

otherwise healthy women with normal CD4+ T-cell counts and low HIV RNA levels may discontinue treatment after delivery and be closely monitored according to adult guidelines

The exception is the woman who plans another pregnancy in the near future

REFERENCES

William’s Obstetrics 24th edition Textbook of Obstetrics by Sheila Balakrishnan Uptodate.com