Respiratory community-acquired and healthcare-related sepsis: are they different?

Introduction

Respiratory infection counts for more than one-half of all admissions to the ICU with sepsis. In this study the epidemiology and microbiological profile of community-acquired and healthcare-related (HCR) respiratory sepsis will be described.

Methods

A prospective, observational study of all the patients with community-acquired sepsis (CAS) admitted to our ICU, over 1 year. Respiratory CAS was defined by the presence of respiratory infection and at least two SIRS criteria at the time of hospital admission or within the first 48 hours. HCR infection was defined according to criteria proposed by Friedman and colleagues [1].

Results

In the study period, 347 patients were admitted – 149 (43%) with CAS. Respiratory infection was present in 102 patients (68%). Comparing this group with nonrespiratory CAS, 73% versus 51% were male (P = 0.01), with a similar median age of 57 years versus 62 years (P = 0.334), more severe sepsis (40% vs 28%) and less septic shock (46% vs 68%) (P = 0.030). Blood cultures were obtained in 96 (94%) patients, only 8% were positive versus 39% in nonrespiratory CAS (P < 0.001). Gram-positive microorganisms represented 51% of all isolations, Gram-negative 26%, Mycobacterium tuberculosis 6%, atypical 5%, and fungus represented only 2% of all isolations. Polymicrobian infections were documented in 5% of the patients. HCR respiratory infection was present in 17%. Gram-positive microorganisms represented 50% of all isolations, and Gram-negative 37%. ICU length of stay (9 vs 8 days, P = 0.595), as well as ICU (35% vs 32%, P = 0.686) and hospital (36% vs 41%, P = 0.559) mortality were similar between respiratory and non-respiratory CAS.

Conclusion

Respiratory CAS is a very important problem in the ICU, representing 30% of all admissions. Although the microbiological profile is similar to that described in the literature, in this population tuberculosis still plays a representative role and needs to be considered. In this population, no significant differences in the microbiological profile were seen between CAS and HCR infection.