Long-Term follow-up of Premature Infants with Urinary Tract Infection

Introduction: Urinary tract infections (UTI) are common in premature infants. We assessed the long-term outcomes and recurrence rate of UTI in adolescents that were born premature.

Methods: Data on preterm infants diagnosed with UTI during 1996- 2008 at the neonatal intensive care unit of Schneider Children’s Medical Center were obtained. Patients with prenatal diagnosis of kidney and urinary tract abnormalities (CAKUT) were excluded. Eligible individuals were invited for evaluation in the nephrology clinic including - weight, height, blood pressure, blood creatinine; urine protein/creatinine, albumin/creatinine ratio. Questionnaires assessed UTI recurrence. Those who did not attend were interviewed by phone.

Results: Of 89 preterm infants with UTI, 23 were lost to follow-up, seven were excluded. None of 18 individuals who arrived for evaluation had UTI recurrence (mean gestational age 29.4 weeks, current mean age 17.1 years, 16 males (89%)). All had normal kidney function. Four (22%) had systolic blood pressure >90^th percentile, three of these (75%) were overweight (>85% BMI).
None had proteinuria or albuminuria (mean protein/creatinine ratio 0.09 mg/dL, albumin/creatinine ratio 10.2 mcg/mgCr). Renal ultrasonography done in the first years of life in 12 (66%) demonstrated normal kidney size and structure. None of 41 interviewed by phone reported problems related to kidney function.

Conclusions: Single episode of UTI in long-term follow-up of premature infants without CAKUT does not constitute a risk factor for UTI recurrence or impairment in renal function in the first two decades of life. Thus, for premature patients with UTI, further imaging and long-term nephrology follow-up are unnecessary.