From the Guidelines
Pyelonephritis in pregnancy should be treated with intravenous antibiotics, such as a fluoroquinolone, an aminoglycoside, or an extended-spectrum cephalosporin, followed by oral therapy, with a total treatment duration of 10-14 days, as recommended by the European Association of Urology guidelines 1. The initial management of pyelonephritis in pregnancy includes hospitalization for intravenous antibiotics, such as ceftriaxone or an extended-spectrum cephalosporin 1. After clinical improvement, typically within 24-48 hours, transition to oral antibiotics like cephalexin or amoxicillin-clavulanate can be considered 1. It is essential to note that fluoroquinolones and cephalosporins are the only antimicrobial agents recommended for oral empiric treatment of uncomplicated pyelonephritis 1. Urine culture with susceptibility testing should guide antibiotic selection, and adequate hydration and antipyretics for fever are important supportive measures 1. Pyelonephritis requires aggressive treatment in pregnancy, as it increases the risks of preterm labor, low birth weight, and maternal sepsis 1. Follow-up urine cultures are recommended after completing treatment to ensure cure, and monthly urine screening throughout pregnancy may be warranted to detect recurrence early 1. Nitrofurantoin and fluoroquinolones should generally be avoided in pregnancy when alternatives exist, due to insufficient data regarding their efficacy and potential risks 1. Key considerations in the management of pyelonephritis in pregnancy include:
- Prompt differentiation between uncomplicated and potentially obstructive pyelonephritis
- Use of appropriate imaging techniques, such as ultrasound or MRI, to evaluate the upper urinary tract and rule out urinary tract obstruction or renal stone disease
- Avoidance of radiation risk to the fetus
- Tailoring treatment to local policies and resistance patterns
- Monitoring for clinical and microbiological success, as well as potential recurrence.
From the FDA Drug Label
Pregnancy Teratogenic Effects Pregnancy Category B Cefepime was not teratogenic or embryocidal when administered during the period of organogenesis to rats at doses up to 1000 mg/kg/day (1. 6 times the recommended maximum human dose calculated on a mg/m2 basis) or to mice at doses up to 1200 mg/kg (approximately equal to the recommended maximum human dose calculated on a mg/m2 basis) or to rabbits at a dose level of 100 mg/kg (0. 3 times the recommended maximum human dose calculated on a mg/m2 basis). There are, however, no adequate and well-controlled studies of cefepime use in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed. Uncomplicated and Complicated Urinary Tract Infections (including pyelonephritis) caused by Escherichia coli or Klebsiellapneumoniae, when the infection is severe, or caused by Escherichia coli, Klebsiellapneumoniae, or Proteus mirabilis, when the infection is mild to moderate, including cases associated with concurrent bacteremia with these microorganisms
- Cefepime dosage for pyelonephritis in pregnancy: The recommended dosage for uncomplicated and complicated urinary tract infections, including pyelonephritis, is 0.5 to 1 g IV every 12 hours for 7 to 10 days for mild to moderate infections, and 2 g IV every 12 hours for 10 days for severe infections 2.
- Precautions: Cefepime should be used during pregnancy only if clearly needed, as there are no adequate and well-controlled studies of cefepime use in pregnant women 2.
- Key considerations:
- The dosage of cefepime for injection should be adjusted in patients with renal impairment, including those with creatinine clearance less than or equal to 60 mL/min 2.
- Cefepime is excreted in human breast milk in very low concentrations, and caution should be exercised when cefepime is administered to a nursing woman 2.
From the Research
Treatment Options for Pyelonephritis in Pregnancy
- Outpatient treatment of pyelonephritis in pregnancy is effective and safe in selected patients, as shown in a randomized controlled trial 3.
- A study comparing once-a-day ceftriaxone versus multiple doses of cefazolin found that both treatments were effective in treating acute pyelonephritis in pregnancy 4.
- The choice of antibiotic should consider antimicrobial resistance patterns in the local community, and there is a growing concern about antimicrobial resistance to commonly prescribed medications for urinary tract infections in pregnancy 5.
Antibiotic Regimens
- Ceftriaxone and cefazolin are commonly used antibiotics for treating pyelonephritis in pregnancy, with ceftriaxone being effective as a single daily dose 4.
- Oral cephalexin is often used to complete a 10-day course of treatment after initial intravenous or intramuscular antibiotic therapy 3, 6.
- Fluoroquinolones, such as ciprofloxacin and levofloxacin, are effective in treating acute uncomplicated pyelonephritis, but their use should be cautious due to rising resistance rates and potential side effects 7.
Inpatient vs. Outpatient Treatment
- A study found that outpatient treatment of acute pyelonephritis in pregnancy after 24 weeks was effective, but 30% of outpatients were unable to complete their assigned protocol, and most women with acute pyelonephritis in the third trimester were not candidates for outpatient therapy 6.
- Inpatient treatment is often necessary for women with severe symptoms or those who do not respond to initial outpatient treatment 3, 6.