Impact of urinary tract infection on nursing and healthcare-associated pneumonia

Abstract

Nursing and healthcare-associated pneumonia (NHCAP), a concept of pneumonia proposed by the Japanese Respiratory Society, mostly occurs among elderly people in long-term care facilities. Similarly, the risk of urinary tract infection (UTI) also increases with age, with UTIs common among those in long-term care. Therefore, NHCAP is sometimes complicated by the presence of a UTI. However, pneumonia complicated by a UTI has not been clinically well characterized. We retrospectively analyzed 376 patients with NHCAP admitted to our hospital over a three-year period. Sixty-seven patients (17.8%) showed complications by a UTI. Patients with a UTI had lower renal function (higher blood urea nitrogen [P = 0.001], higher creatinine [P = 0.001]), lower systolic blood pressure (P = 0.04), higher A-DROP scores (P = 0.005) and higher positive blood culture rates (P = 0.03) than those without a UTI. Furthermore, based on urine, sputum and blood culture results, nearly half of the microorganisms (4/7) in blood cultures were identical with those of urine, suggesting that a concurrent UTI increases positive blood culture rates. Multivariate analysis showed that UTI was not an independent factor associated with 30-day mortality (P = 0.17), although patients with a UTI showed higher 30-day mortality (P = 0.04) than those without a UTI in univariate analysis. In summary, patients with NHCAP and a UTI were more prone to complications than those without a UTI, although UTI itself did not affect the prognosis of patients with NHCAP. A concurrent UTI had a negative impact on the severity of NHCAP.