Eosinophilic fasciitis: A case report and literature review.

RATIONALE: Eosinophilic fasciitis (EF) is a rare fibrosing disorder with an undetermined etiology and an incompletely elucidated pathogenesis. Although eosinophilia is frequently observed during the acute phase and serves as a diagnostically suggestive feature, its absence does not exclude active disease. Notably, the incidence of eosinophilia shows a progressive decline in chronic cases, correlating with the disease duration and fibrotic progression.

PATIENT CONCERNS: A 42-year-old male manual laborer presented with a 12-month history of progressive symmetric induration and hyperpigmentation affecting all 4 limbs.

DIAGNOSES: Blood tests revealed eosinophilia (1.52 × 10⁹/L), and magnetic resonance imaging demonstrated characteristic hyperintensity of the fascial layers on T2-weighted imaging.

INTERVENTIONS: The patient was initially treated with low-dose corticosteroids combined with methotrexate.

OUTCOMES: Laboratory monitoring confirmed complete normalization of the previously elevated peripheral eosinophil count, indicating a favorable treatment response.

LESSONS: EF is a rare connective tissue disorder that frequently poses diagnostic challenges, often leading to missed or incorrect diagnoses in clinical practice. However, contemporary diagnostic approaches enable the accurate identification of suspected EF cases through comprehensive evaluation of characteristic clinical manifestations, laboratory findings, and imaging features, even in the absence of confirmatory biopsy.