Clinical Characteristics and Antimicrobial Susceptibility of Elderly Women with Acute Pyelonephritis

Abstract

Background and objectives Acute pyelonephritis is a urinary tract infection with a relatively high prevalence in women of all ages. In older patients, its symptoms are more severe, leading to worse treatment response and prognosis. The objective of this study was to classify older female patients with acute pyelonephritis by age and compared their clinical characteristics and antibiotic susceptibility. Materials and methods In this retrospective study, 360 older patients aged 65 years or over who were hospitalized for acute pyelonephritis in a single tertiary medical facility from 2012 to 2016 were selected as research subjects. They were divided into three groups according to their age to compare their clinical symptoms, blood tests and urinalysis, underlying diseases, urinary tract infections, and antibiotic susceptibility. Results A total of 176 patients aged 69.9 ± 2.7 years, 142 patients aged 79.4 ± 3.1 years, and 42 patients aged 87.3 ± 3.1 years were assigned into the young-old, old-old, and oldest-old groups, respectively. The duration of hospitalization (7.0 ± 1.7 vs 7.8 ± 2.6 vs 12.6 ± 2.9, P < 0.05) and duration of fever (3.2 ± 1.0 vs 3.8 ± 0.8 vs 5.1 ± 1.6, P < 0.05) due to acute pyelonephritis increased with age. However, the maximum body temperature did not differ among groups (39.0 ± 1.2 vs 39.3 ± 0.9 vs 39.0 ± 0.6 P < 0.061). In blood tests, ESR (97.1 ± 20.3 vs 107.0 ± 25.2 vs 109.7 ± 30.5, P < 0.05) and CRP (11.6 ± 4.7 vs 13.3 ± 5.0 vs 15.7 ± 5.2, P < 0.05) increased with age. Among underlying diseases, diabetes (P = 0.245) and chronic renal disease (P = 0.075) did not differ among groups while cerebrovascular diseases, heart failure, and urinary stone were associated with aging. The older a patient was, the more she was likely to have UTI over the past year (5.7% vs 16.2% vs 33.3%, P < 0.05). Older groups showed more statistically significant decrease in sensitivity to ertapenem (99.4% vs 95.1 vs 94.9%, P < 0.05) and imipenem (97.7% vs 92.3 vs 90.5%, P < 0.05) belonging to carbapenem class antibiotics. For amikacin, older groups showed lower sensitivity (97.1% vs 91.6 vs 84.6%, P < 0.05). For ciprofloxacin, older group showed more significant decrease in sensitivity (68.2% vs 58.2% vs 47.6%, P < 0.05). Conclusions Acute pyelonephritis in older patients showed significant differences in clinical progress, test results, and sensitivity to major antibiotics according to age. Therefore, choosing antibiotics in consideration of ages of patients is important when treating patients with acute pyelonephritis.