Eosinopenia: An Early Clue to Salmonella Gastroenteritis

Background: Eosinopenia is recognized in a variety of infectious diseases. However the underlying mechanism in infection, and more specifically in Salmonella infection, is unclear. We know that in healthy people, eosinophils principally reside at mucosal surfaces including the gut mucosa, and it is possible that increased marginalization of these cells during infection at this site may account for the early and marked decrease.

Objective: Compare eosinophils count of the hospitalized pediatric population with Acute Bacterial Gastroenteritis (ABG), according to the isolated agent.

Methods: Retrospective descriptive study, with analysis of laboratory findings of all children with positive stool cultures hospitalized in a Portuguese district hospital between January 2012 and December 2018 (7 years).

Statistical software SPSS for Windows was used. A p value less than 0.05 was considered statistically significant.

Results: During our study period, 32 (54.24%) children with ABG were hospitalized, 41.18% of those with Campylobacter spp infection and 72% of those with Salmonella spp infection.

Eosinophils count were performed in practically all hospitalized children (n=31). The median number of eosinophils was significantly lower in patients with Salmonella gastroenteritis (40 eosinophils/µL), compared to Campylobacter group (110 eosinophils/µL) and to those admitted with acute diarrhoea whose stool cultures were negative (n = 52; 210 eosinophils/µL). Furthermore almost all children (94.12%) with ABG by Salmonella revealed eosinopenia (

Conclusion: This study is one of the few that reported a positive association between eosinopenia and Salmonella infection. This can be an early important diagnostic clue to an infection by this agent before stool culture results become available. This information can aid in the decision of hospitalization in selected cases.