Diagnosis of systemic lupus erythematosus by presence of Hargraves cells in eosinophilic pleural effusion: Case report.

Rationale: Eosinophilic pleural effusion in elderly patients is most commonly due to malignancies and infections.

Patient Concerns: In rare cases, pleural eosinophilia is associated with connective tissue disease.

Diagnoses: Presence of Hargraves cells, also called lupus erythematosus (LE) cells (polynuclear cells that have engulfed denatured nuclear material), was a key point of American College of Rheumatology (ACR) classification criteria for systemic lupus erythematosus (SLE) until 1997.