Pyelonephritis may occur postpartum if bacteria ascend from the bladder. The infection may begin as asymptomatic bacteriuria during pregnancy and is sometimes associated with bladder catheterization to relieve urinary distention during or after labor. The causative organism is usually a type of coliform bacteria (eg, Escherichia coli).
Symptoms of pyelonephritis include fever, flank pain, general malaise, and, occasionally, painful urination.
Diagnosis of pyelonephritis is based on urinalysis, urine culture, and clinical findings.
Initial treatment of pyelonephritis is ceftriaxone 1 to 2 g IV every 12 to 24 hours alone or ampicillin 1 g IV every 6 hours plus gentamicin 1.5 mg/kg IV every 8 hours until women are afebrile for 48 hours.
Sensitivities with culture should be checked. Treatment is adjusted accordingly and continued for a total of 7 to 14 days; oral antibiotics are used after the initial IV antibiotics.
Women should be encouraged to consume large amounts of liquids.
A urine culture should be repeated 6 to 8 weeks after delivery to verify cure. If episodes of pyelonephritis recur, imaging should be considered to look for calculi or congenital malformations. Imaging during pregnancy is usually with ultrasonography; imaging after pregnancy is usually with contrast CT.