Peripheral blood eosinophilia in association with sarcoidosis

Objectives: To review retrospectively our experience with peripheral blood eosinophilia (PBE) in sarcoidosis and to analyze histologically lung biopsy specimens for the presence of lung tissue eosinophils. Patients and Methods: We reviewed 140 cases of sarcoidosis diagnosed betwee n May 1975 and January 1998, Ninety-five patients (66.3% women; 70.5% Afric an American; mean age, 35.9 years) met the inclusion criteria. Transbronchi al biopsy specimens from 82 patients mere divided into 4 morphologic compar tments: parenchyma, bronchial wall, parenchymal granulomas, and bronchial w all granulomas, Within compartments, up to 10 highpower fields were scored semiquantitatively for eosinophils, from 0 (none) to 4+ (numerous). Results: Thirty-nine patients (41%) had PBE. Four had PBE greater than 10%. The highest eosinophil count (21%) occurred in 1 patient. Sixty-five (79%) of 82 patients had no or few (1+) eosinophils in lung tissue; 17 patients had eosinophils scored as 2+ or higher. There was no correlation between pe ripheral blood eosinophil count and presence of eosinophils in transbronchi al biopsy specimens, Eosinophils were least conspicuous in parenchyma but e venly distributed in bronchial wall and parenchymal and bronchial wall gran ulomas. Conclusions: Peripheral blood eosinophilia occurs frequently in sarcoidosis . However, there appears to be no association between peripheral blood eosi nophil count and presence of lung tissue eosinophils, Whether eosinophils p articipate in the pathogenesis of sarcoidosis requires further study.