A 72-year-old man with a personal history of hypertension, chronic obstructive pulmonary disease, ex-smoker and diagnosed with papillary urothelial carcinoma of the bladder (T1G2). Transurethral resection of the tumour was performed and 3 weeks later treatment was started with a long course of endovesical instillations of BCG (Connaught strain, 109 colony-forming units per dose) administered weekly. After receiving 3 sessions, she went to the emergency department for general malaise and fever (38.5ยบ) of ten days' evolution. There was no micturition syndrome or other symptoms. Physical examination was unremarkable with normal pulmonary auscultation, negative bilateral renal fist percussion and a non-painful or congestive prostate, size II/IV and adenomatous consistency. The haemogram showed slight leukocytosis without neutrophilia (leukocytes 12100 and 63.7% neutrophils). Urine and blood cultures were sterile and the search for acid fast bacilli in urine was unsuccessful. Chest X-ray showed bilateral and diffuse involvement of small millimetric nodules with thick calcified lymph nodes, compatible with miliary TB. Computed axial tomography (CT) showed gross calcified adenopathy in the right hilum and pulmonary ligament and bilateral and diffuse parenchymal involvement of small millimetric nodules affecting all lung fields. The patient was admitted and treated with isoniazid, rifampicin and ethambutol. The patient's general condition improved and he was discharged and followed up on an outpatient basis. During follow-up, there were no adverse effects of the medication and no new febrile episodes or other symptoms. Anti-tuberculosis treatment was continued for 6 months and BCG instillations were discontinued. The control CT scan at two months showed a decrease in the size of the adenopathies as well as a decrease in the number of nodules, with complete disappearance in some lung segments.