What does this research mean for the field?

Most parasitic infections cause only mild to moderate eosinophilia, and an absolute eosinophil count greater than 30,000/µL is rarely due to parasitic infection and should instead prompt evaluation for non-infectious causes such as malignancy. Novelty: ClaimNovelty.INCREMENTAL. Consensus alignment: ConsensusAlignment.NEUTRAL.

What question did this study set out to answer?

To assess whether peak absolute eosinophil count and serum IgE levels can reliably distinguish parasitic infections from non-parasitic etiologies in patients presenting with marked eosinophilia.

August 28, 2026Clinical Infectious Diseases

How High is Too High? The Diagnostic Value of Absolute Eosinophil Count in Excluding Parasitic Infection

View Full Paper

Ask AI

Bookmark

Authors

JBJessica BassNational Institutes of Health EFEvgenii FilippovNational Institute of Allergy and Infectious Diseases JKJoseph KubofcikNational Institute of Allergy and Infectious Diseases

Discussion

Member takes

Implication

Retrospective study reveals peak eosinophil levels rarely exceed 30,000 cells/µL in parasitic disease, indicating extremely high counts warrant urgent workup for malignancies.

Key Points

To assess whether peak absolute eosinophil count and serum IgE levels can reliably distinguish parasitic infections from non-parasitic etiologies in patients presenting with marked eosinophilia.
Conducted a retrospective chart review of 1,025 patients (907 adults and 118 children) with peak absolute eosinophil count (AEC) ≥500/µL enrolled in NIH protocols between 1974 and 2024.
Retested archived serum samples with species-specific serologies to clarify suspected parasitic diagnoses when clinically indicated.
Parasitic infections were diagnosed in 360 patients, who demonstrated significantly lower median peak AEC than non-parasitic cases, with only 2 patients (both pediatric visceral larva migrans cases) having an AEC >30,000/µL.
ROC curve analysis identified AEC cutoffs of 28,680/µL in adults and 59,529 cells/µL in children for excluding parasitic infection with near 100% specificity.
In adults, parasitic causes decreased while malignancy-associated eosinophilia rose with higher AEC (χ2_trend = 84.69, P < 0.0001), whereas serum IgE displayed high variability without diagnostic utility.

Cite This Study

Bass et al. (2026) studied this question.

synapsesocial.com/papers/6a916ea0d15324a1df3aa7e8 https://doi.org/10.1093/cid/ciag513

View Full Paper

Ask AI

Bookmark

Implication

Retrospective study reveals peak eosinophil levels rarely exceed 30,000 cells/µL in parasitic disease, indicating extremely high counts warrant urgent workup for malignancies.

How High is Too High? The Diagnostic Value of Absolute Eosinophil Count in Excluding Parasitic Infection

Discussion

Member takes

Implication

Key Points

Cite This Study

How High is Too High? The Diagnostic Value of Absolute Eosinophil Count in Excluding Parasitic Infection

Discussion

Member takes

Implication

Key Points

Cite This Study

Also Consider

Also Consider