L-tryptophan-associated eosinophilic fasciitis prior to the 1989 eosinophilia-myalgia syndrome outbreak.

OBJECTIVE

To investigate the relationship between L-tryptophan (LT) ingestion and eosinophilic fasciitis (EF) occurring prior to the outbreak of eosinophilia-myalgia syndrome in 1989.

METHODS

Interviews and record reviews of 45 EF case-patients and 126 polymyositis patients (controls) diagnosed prior to 1988.

RESULTS

Nine case-patients (20%) and no controls recalled taking LT before onset of the disease (odds ratio = infinity, 95% confidence interval = 8.3-infinity). Among EF case-patients, LT ingestion was associated with dyspnea.

CONCLUSION

LT ingestion was associated with EF prior to the 1989 outbreak of eosinophilia-myalgia syndrome. Lung abnormalities may be a distinguishing feature of LT-mediated illness.