Leukocyte migration inhibition in propranolol-induced pneumonitis. Evidence for an immunologic cell-mediated mechanism

About 20 cases of beta blocker-associated pneumonitis have been published in the mid-70s, and a case of interstitial pneumonitis has been attributed to propranolol. The pathogenesis of these cases of pneumonitis with or without pleural effusion is not clear. A 59-year-old man developed pneumonitis which showed all the characteristics of a drug-associated pneumonitis due to propranolol: BAL demonstrated a lymphocytosis, the variations of which closely correlated with a provocation test. The LIF appeared to be released by the patient's peripheral blood lymphocytes when cultured with optimal doses of propranolol. Production of LIF by the patients' lymphocytes suggests the existence of a drug-specific cellular immune response in propranolol-associated pneumonitis.