Is eosinopenia a reliable marker of sepsis?

cc7877 CCJ Letter Is eosinopenia a reliable marker of sepsis? Smithson Alex asa30412@hotmail.com Perelló Rafael rperello@clinic.ub.es Nicolas Josep-Maria rperello@clinic.ub.es

Infectious Diseases Unit, Hospital Clínic, IDIBAPS, University of Barcelona, 08036 Barcelona, Spain

Emergency Department, Hospital Clínic, IDIBAPS, University of Barcelona, 08036 Barcelona, Spain

Medical Intensive Care Unit, Hospital Clínic, IDIBAPS, University of Barcelona, 08036 Barcelona, Spain

Critical Care 1364-8535 2009 13 3 409 http://ccforum.com/content/13/3/409 See related research by Abidi et al., http://ccforum.com/content/12/2/R59 1951994410.1186/cc7877 1 6 2009 2009 BioMed Central Ltd

We have read with interest the article by Abidi and colleagues 1 in which the authors point out that eosinopenia could be useful to differentiate between noninfection and infection in patients recently admitted to an intensive care unit (ICU). The association of eosinopenia with infections is not new and has been described previously 2.

To test this hypothesis, we reviewed 191 patients (age >18 years, with a minimum ICU stay of 24 hours) admitted to the medical ICU of our hospital. We exuded HIV-infected patients and those with hematological malignancies. Total leukocyte and eosinophil count (EC) were measured at ICU admission. The results are shown in Table 1. Although the EC was lower and the proportion of patients with eosinopenia (<40 cells/ml) was higher in the noninfectious systemic inflammatory response syndrome (SIRS) group compared with the infectious SIRS group, these differences were not statistically significant. Therefore, the EC was not useful to distinguish between infection and noninfection. Although one limitation of our study was the absence of a non-SIRS group, the EC of our noninfectious SIRS group was similar to the EC found in the non-SIRS group in the study by Abidi and colleagues 1. Another study failed to observe an association between eosinopenia and bacteremia 3.

Table 1

Baseline characteristics of the ICU patients included in the study

Infectious SIRS (n = 142)

Noninfectious SIRS (n = 49)

P-value*

Age (years)

62.7 ± 15.3

66.8 ± 14.3

0.1

APACHE II score

16.6 ± 6.5

17.8 ± 6

0.27

SAPS II score

36.6 ± 12.1

36.4 ± 11.4

0.95

SOFA score

8.8 ± 3.2

7.7 ± 2.7

0.034

Length of ICU stay (days)

11.4 ± 11.3

7.5 ± 7.8

0.03

Sites of infection

Community-acquired pneumonia

57 (40.1%)

Hospital-acquired pneumonia

9 (6.3%)

Urinary tract infection

11 (7.7%)

Bacterial meningitis

4 (2.8%)

Peritonitis

23 (16.2%)

Other infections

38 (26.7%)

ICU mortality

39 (27.4%)

13 (26.5%)

0.89

Total leukocyte count (cells/ml)

13,497 ± 7,254

10,345 ± 5,569

0.006

Total eosinophil count (cells/ml)

105 ± 220

114 ± 186

0.8

Eosinopenia (<40 cells/ml)

70 (49.3%)

18 (36.7%)

0.12

Data are presented as the mean ± standard deviation or n (%). *Calculated by means of the Student t-test (quantitative variables) and chi-square test (qualitative variables). APACHE, Acute Physiology and Chronic Health Evaluation; ICU, intensive care unit; NA, not applicable; SAPS, Simplified Acute Physiology Score; SIRS, systemic inflammatory response syndrome; SOFA, Sequential Organ Failure Assessment.

In conclusion, eosinopenia was not a reliable marker of infection. Other analytical parameters, such as C-reactive protein, have demonstrated to be helpful not only for the diagnosis of infection but also as a marker of severity of organ dysfunction in sepsis 4.

Authors' response

Khalid Abidi, Ibtissam Khoudri, Jihane Belayachi, Naoufel Madani, Amine Ali Zeggwagh and Redouane Abouqal

Smithson and colleagues, in their letter on our report recently published in Critical Care 1, suggest that eosinopenia is not a reliable marker of infection in critically ill patients. We have demonstrated for the first time that eosinopenia is a good diagnostic marker of infection on ICU admission with good sensitivity and specificity 1.

The study performed by Smithson and colleagues has several limitations that should be considered. First, the retrospective nature of their study could cause methodological limitations, at the least because some data were not available for all patients. Second, to evaluate the usefulness of EC to distinguish between noninfectious and infectious SIRS patients, Smithson and colleagues do not describe how the infection was defined and confirmed. Third, no non-SIRS group was included, although the authors report that the EC in the noninfectious SIRS group was similar to that found in our non-SIRS group. However, ECs for non-SIRS groups from both studies should really be determined for a completely valid comparison.

Abbreviations

EC: eosinophil count; ICU: intensive care unit; SIRS: systemic inflammatory response syndrome.

Competing interests

The authors declare that they have no competing interests.

Eosinopenia is a reliable marker of sepsis on admission to medical intensive care units Abidi K Khoudri I Belayachi J Madani N Zekraoui A Zeggwagh AA Abouqal R Crit Care 2008 12 R59 2447615 18435836 10.1186/cc6883 Value of eosinopenia in inflammatory disorders: an "old" marker revisited Gil H Magy N Mauny F Dupond JL Rev Med Interne 2003 24 431 435 12829215 Utility of eosinophil count as predictor of bacteremia Setterberg MJ Newman W Potti A Smego RA Jr Clin Infect Dis 2004 38 460 461 10.1086/380846 14727227 Procalcitonin and C-reactive protein during systemic inflammatory response syndrome, sepsis and organ dysfunction Castelli GP Poqnani C Meisner M Stuani A Bellomi D Sqarbi L Crit Care 2004 8 R234 R242 522844 15312223 10.1186/cc2877