Eosinophilic appendicitis due to Strongyloides stercoralis: a challenging differential diagnosis for clinicians

Abstract

A 45-year-old man presents with 48-hour status of high temperature, cough and dyspnoea. In the context of pandemic, the patient is initially diagnosed with COVID-19 syndrome. Later, the laboratory and ultrasound study supported acute appendicitis diagnosis. Appendicectomy was performed. The histopathology study confirmed eosinophilic appendicitis and that a parasitic infection was suspected. The stool sample was positive for Strongyloides stercoralis The diagnosis of a S stercoralis is a rare finding in Spain. S. stercoralis simulates clinical findings of inflammatory bowel disease or eosinophilic gastroenteritis, which may lead to the wrong therapeutic choice. Since in inflammatory diseases corticosteroid treatments are considered the initial choice in many cases, in the case of S. stercoralis infection, the administration of this therapy can be fatal. In Spain, the number of diagnoses is much lower than in the past decade, although it is highly probable that the infection has been underdiagnosed due to low clinical awareness among Spanish population.

Keywords: infection (gastroenterology); infectious diseases; medical management.

Figure 1

X-ray chest examination where we observed a mild consolidation in the right lower pulmonary lobe.

Figure 2

(A) At ×20 objective lens magnification, a large eosinophilic infiltrate at the mucosa level is observed. (B) At ×40 magnification, we can see an eosinophilic infiltrate that permeates the glandular epithelium. Degranulated eosinophils are observed. (C) At ×20 magnification, serosal eosinophils and reactive hyperplasia of the mesothelials are observed. (D) At ×40 magnification, a gland with proeosinophilic crypt microabscess is observed.