1238. Clinical Prediction Rules for Bacteremia Based on Appetite at The Time of Blood Culture
Session: Poster Abstract Session: Sepsis and Critical Care
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Fever is one of the most common symptoms of hospitalized patients suggesting infection. In this setting, blood cultures are the gold standard test to distinguish bacteremia from other causes. But the yield of blood cultures is relatively low, frequently showing many false positive results from bacterial contamination. False positive reports may lead to unnecessary antibiotic therapy, longer hospitalization and increased cost. Existing prediction models for assessing the risk of bacteremia are complex and difficult to use. In this study, we aimed to investigate the relationship between patient appetite and the presence of bacteremia.

Methods: We retrospectively analyzed 1509 patients (68.0 +/- 17.5 years old, % males; 44.5%) with acute febrile illness at a community hospital in Tokyo, Japan between 2005-2010 inclusive. Patients with anorexia-inducing conditions such as gastrointestinal illness and malignant disease treated with chemotherapy were excluded. Patients aged less than six years old were also excluded from the study. Appetite was rated on a percentage scale of how much the patient could eat, and this determined the patient groupings as follows;  Group 1 (less than 50%), Group 2 (more than 50% to less than 80%), Group 3 (more than 80%).  

Results: Each group consisted of the following; Group 1; 54.0% of patients, Group 2; 12.4% of patients, and Group 3; 33.6% of patients.The average body temperature was 38.2 +/- 0.9°C. The most common pathogen family was Enterobacteriaceae in 53.1% of patients. Bacteremia occurred in 29.6%, 7.1% and 2.6% of patients in Groups 1, 2 and 3, respectively. The sensitivity of the good appetite was very high (95.0%) in the context of negative blood culture results although such a symptom was not of high specificity (39.8%). The negative predictive value was 96.9% and the negative likelihood was 0.12. These data confirming suggesting that the presence of a good appetite were inversely related to possibility of blood cultures.

Conclusion: Bacteremia is an unlikely occurrence in patients who maintain a good appetite at the time of blood culture acquisition despite elevations in body temperature that might otherwise suggest systemic infection.

Subject Category: J. Clinical practice issues

Takayuki Komatsu, MD1, Toshihito Onda, MD1, Go Murayama, MD1, Masashi Yamanouchi, MD1, Joel Branch, MD2 and Kenji Inoue, MD, PhD3, (1)Juntendo University Nerima Hospital, Tokyo, Japan, (2)Shonan Kamakura General Hospital, Kanagawa, Japan, (3)Cardiology, Juntendo University Nerima Hospital, Tokyo, Japan


T. Komatsu, None

T. Onda, None

G. Murayama, None

M. Yamanouchi, None

J. Branch, None

K. Inoue, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.