Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jul;51(7):902-914.
doi: 10.1111/cea.13889. Epub 2021 Jun 3.

The causes of a peripheral blood eosinophilia in a secondary care setting

Andrew John Wardlaw  1 , Sarah Wharin  2 , Hnin Aung  1 , Shireen Shaffu  3 , Salman Siddiqui  1
Affiliations

The causes of a peripheral blood eosinophilia in a secondary care setting

Andrew John Wardlaw et al. Clin Exp Allergy. 2021 Jul.

Abstract

Background: A peripheral blood eosinophilia of greater than 1.0 × 109 /L is relatively unusual and offers a clue to the underlying diagnosis. In 2003, we established a specialist service to diagnose unexplained eosinophilia.

Objective: To describe the causes of an eosinophilia in our service and the diagnostic algorithm we developed.

Methods: Subjects were referred by physician colleagues across a range of specialties and undertook standard investigations following a semi-structured protocol. Data were extracted from a bespoke database.

Results: Three hundred and eighty two subjects were referred over a 17-year period. Average age was 54 years and 183 (48%) of subjects were female, with 21 of 25 (84%) females in the idiopathic eosinophilic pneumonia group (p < 0001), 22 of 30 (73%) females in the gastrointestinal disease group (p < .008), but 11 of 37 (30%) females in the eosinophilic granulomatosis with polyangiitis group (p < .04). A diagnosis was assigned after systematic evaluation using a pre-defined algorithm in 361 (94.5%) of cases. Fungal allergy (82 subjects: 21%), parasitic infection (61 subjects: 16%) and severe eosinophilic asthma (50 subjects: 13%) were the three commonest individual diagnoses. Hypereosinophilic syndrome (HES) disease including eosinophilic granulomatosis with polyangiitis (EGPA) accounted for 85 subjects (20%) of which seven subjects (2%) had myeloproliferative disease (M-HES). A high IgE was common, and 79 (91%) of subjects with complete data who had an IgE of ≥1000 IU/L had fungal allergy or parasite infection. The serum tryptase was raised in 44 of 302 (14.5%) of individuals across all diagnostic groups, though none had mastocytosis.

Conclusion: A diagnosis of an unexplained eosinophilia can usually be determined using as semi-structured algorithm. Parasitic infection and fungal allergy often with severe eosinophilic asthma were common causes, whereas HES, particularly myeloproliferative, disease was relatively rare.

Keywords: EGPA; IgE; eosinophils; fungal; hypereosinophilic syndrome; parasites.

PubMed Disclaimer

References

REFERENCES

    1. Jacobsen EA, Jackson DJ, Heffler E, et al. Eosinophil knockout humans: uncovering the role of eosinophils through eosinophil-directed biological therapies. Annu Rev Immunol. 2021;39(1):719-757.
    1. Klion AD, Ackerman SJ, Bochner BS. Contributions of eosinophils to human health and disease. Annu Rev Pathol. 2020;15:179-209.
    1. Yancey SW, Keene ON, Albers FC, et al. Biomarkers for severe eosinophilic asthma. J Allergy Clin Immunol. 2017;140(6):1509-1518.
    1. Hartl S, Breyer MK, Burghuber OC, et al. Blood eosinophil count in the general population: typical values and potential confounders. Eur Respir J. 2020;55(5):1901874.
    1. Rothenberg ME, Hogan SP. The eosinophil. Annu Rev Immunol. 2006;24:147-174.

Publication types

Grants and funding