What Are the Clinical Features and Etiology of Eosinophilic Liver Infiltration?

Abstract

Background/AimsAlthough eosinophilic liver infiltration (ELI) is not rare, few data exist regarding its clinical characteristics and etiology. Therefore, we evaluated these aspects to better understand the clinical implications of this lesion type, which is reasonably common in Korea.MethodsPatients suspected of having ELI, based on abdominal computed tomography results obtained between January 2010 and September 2017, were enrolled in this retrospective study. The presumptive etiologies of ELI were categorized as parasite infections, hypereosinophilic syndrome (HES), eosinophilic granulomatosis with polyangiitis (EGPA), malignancies, and unidentified. Clinical courses and treatment responses were also evaluated.ResultsThe mean age of the enrolled patients (male, 237/328) was 62 years. Most patients (63%) were diagnosed incidentally and had peripheral eosinophilia (90%). Only 38% of the enrolled patients (n=126) underwent further evaluations to elucidate the etiology of the suspected ELI; 82 (25%) had parasite infections, 31 (9%) had HES, five (2%) had EGPA, and five (2%) had drug reactions in conjunction with eosinophilia and systemic symptoms. Almost half of the other enrolled patients had cancer. Radiologic resolution was achieved in 191 patients (61%; median time to radiologic resolution, 185 days). Resolution of peripheral eosinophilia was achieved in 220 patients (79%). In most cases, the course of ELI was benign.ConclusionsThis large ELI study is unique in that the incidence rate, underlying diseases, and clinical courses were comprehensively evaluated. Clinicians should investigate the etiology of ELI, as several of the underlying diseases require intervention rather than observation.

Focal eosinophilic infiltration of the liver, benign or malignant?

“…Further diagnostic steps should thus be undertaken when encountering FEI/(hyper)eosinophilia. 3 , 4 The most common cause is parasitic infection, with Toxocara canis, Fasciola hepatica, Clonorchis sinensis, Spirometra mansonoides and Taenia solium being reported as frequent culprits. 17 Other possible causes are drug reactions, atopic disorders, eosinophilic granulomatosis with polyangiitis, HES, and paraneoplastic eosinophilia with infiltration of the liver.…”

“…A patient with cytopenias and splenomegaly might be referred to a hematologist. While up to 9% of patients with suspected FEI end being diagnosed with HES 3 and up to 16% are eventually diagnosed with paraneoplastic eosinophilia, 4 a recent retrospective analysis showed that a large portion of patients do not receive further investigation beyond whole blood cell and eosinophilic cell count. 3 In a large portion of patients with FEI, the cause is never identified, possibly due to lack of further investigation.…”

“…The appearance of liver lesions on imaging studies with concomitant (hyper)eosinophilia is not uncommon, with reported incidence of 0.41%-0.68% of all abdominal CT F I G U R E 1 PET-CT of liver shows a hypodense nodule in segment 5-6 with heightened metabolic activity scans. 3,4 Upon encountering suspicious liver lesions, the clinician should promptly assess possible malignant disease. A liver biopsy will provide the definitive answer, but this is invasive.…”

“…3 Reported causes are parasitic infection, atopic disorders, drug hypersensitivity reactions, hypereosinophilic syndrome (HES), connective tissue diseases, and paraneoplastic eosinophilia. 3 Upon correction of the cause of eosinophilia, the prognosis of FEI is good. 4 Based on imaging characteristics, lesions are often misinterpreted as suspected primary hepatic neoplasms or metastases, especially in a prior context of malignancy, leading to (invasive) diagnostic testing and/or inadequate treatment.…”

“…It is not uncommon, but discovery is mostly incidental due to increased use of imaging in often asymptomatic patients 3 . Reported causes are parasitic infection, atopic disorders, drug hypersensitivity reactions, hypereosinophilic syndrome (HES), connective tissue diseases, and paraneoplastic eosinophilia 3 . Upon correction of the cause of eosinophilia, the prognosis of FEI is good 4 …”