D3.58 - Eosinophilic ascites and extreme hypereosinophilia: differential diagnosis through medical treatment

Background:

Eosinophilic ascites is a rare manifestation associated with subserosal eosinophilic gastroenteritis, tissue-invasive helminth infections (Strongyloides, Toxocara, Schistosoma), hypereosinophilic syndrome, hematologic malignancies, and vasculitis. Due to the potential for severe outcomes, an exhaustive differential workup is critical to avoid complications secondary to premature immunosuppression.

Case description:

A 41-year-old woman originally from Morocco and residing in Spain presented with a three-week history of diffuse abdominal pain, vomiting, and diarrhea. Relevant epidemiological factors included contact with sheep and dogs, consumption of untreated water, and ingestion of wild plants (Malva). Computed tomography showed distal ileal wall thickening and moderate ascites. Laboratory workup showed severe peripheral hypereosinophilia (peak 15,600/µL; 69% on peripheral blood smear) and eosinophilic ascites (87.8% eosinophils), with a serum-ascites albumin gradient < 1.1 g/dL.

Parasitic serology and serial stool examinations were negative. Gastroscopy showed H. pylori pangastritis; colonoscopy was macroscopically normal, but ileal and right colonic biopsies revealed eosinophilic infiltrates suggestive of eosinophilic enterocolitis. Prick tests for foods, latex, Anisakis, and panallergens (Pru p 3 and profilin) were negative. Antineutrophil cytoplasmic antibodies were also negative. Myeloid malignancy was excluded by positron emission tomography–computed tomography and molecular studies. Total IgE was 119 IU/mL, and a downward tryptase trend was observed (22.7 to 15.5 µg/L).

Due to the high suspicion of parasitic hyperinfection syndrome and the risk of reactivating latent tuberculosis (QuantiFERON positive), corticosteroids were withheldEmpirical ivermectin and albendazole were administered to treat potential strongyloidiasis and helminthiasis. Despite negative parasitic serologies, the clinical and laboratory abnormalities resolved within 48 hours strongly supported a parasitic etiology. Hereditary alpha-tryptasemia testing is pending.

Conclusion:

This case emphasizes the importance of epidemiological suspicion of parasitic infection in the evaluation of eosinophilic diseases. In patients at risk for parasitic infection, avoiding first-line corticosteroid therapy can prevent serious iatrogenic complications. Therefore, empirical antihelminthic treatment should be considered prior to the initiation of corticosteroids.