Prospective cohort study of acute pyelonephritis in adults: safety of triage towards home based oral antimicrobial treatment.

Objective: Home-based treatment of acute pyelonephritis (AP) is generally reserved for young non-pregnant women who lack co-morbidity. This study, focusing on the elderly and patients with co-morbidity, evaluates the Dutch primary care guideline that recommends referral to hospital only in case of suspected deterioration to severe sepsis or failure of antibiotic treatment, irrespective of patient's age, sex or co-morbidity.
Methods: A prospective observational cohort study including consecutive non-pregnant adults with AP. Clinical and microbiological outcome measures of non-referred patients from 35 primary health care centres (PHC) were compared to patients referred to two affiliating emergency departments (EDs).
Results: Of 395 evaluable patients, 153 were treated by PHCs and 242 referred to EDs. The median age was 63years [IQR 43-77], 34% were male, 58% had co-morbidity; all comparable between the PHC and ED group. Referred ED patients were more likely to have signs of sepsis and to have been pre-treated with antibiotics. Bacteraemia was present in 10% of patients in the PHC group and 27% in the ED group (RR 2.83; 95% CI: 1.64-4.86, p<0.001). Eight (5%) PHC patients were admitted during outpatient treatment but otherwise no major complications occurred. Clinical failure rates at 30days were similar between PHC patients and ED patients; 9% and 10% respectively. Mortality rates of PHC patients versus ED patients were 1% versus 5% at 30days (p=0.058) and 1% versus 7% at 90days (p=0.007). Complicated outcome occurred in 6% of the PHC patients versus 12% in the patients referred to ED (p=0.067).
Conclusion: In a health care system with a well-organized primary care system and clear guideline, the outcome of adults with acute pyelonephritis, including men, the elderly and patients with co-morbidity, selected for oral antibiotic treatment at home did not lead to major complications.
(Copyright 2009 The British Infection Society. Published by Elsevier Ltd. All rights reserved.)