Miliary tuberculosis due to intravesical bacillus Calmette-Guerin therapy

While receiving treatment for bladder carcinoma with intravesical BCG, a 78-year-old man developed a clinical illness and roentgenographic manifestation of miliary tuberculosis. The transbronchial lung biopsy demonstrated granulomas with giant cells. Treatment with antituberculosis therapy resulted in complete resolution of the illness. The pathogenesis of this complication was considered to be due to pulmonary infection by BCG from the bladder source and differs from previously reported cases of interstitial pulmonary infiltrates which more likely represent a hypersensitivity reaction to BCG.