Systemic granulomatous disease and syndrome of inappropriate antidiuretic hormone

A 71-year-old man was admitted with generalized tiredness, mild confusion and low-grade pyrexia following the fourth cycle of intravesical bacillus Calmette–Guerin instillation for the treatment of superficial bladder carcinoma. These symptoms were accompanied by some weight loss which was difficult to quantify. His past medical history included type 1 diabetes mellitus, chronic obstructive pulmonary disease and prostatic hyperplasia. He was a smoker and consumed a moderate amount of alcohol. Physical examination was unremarkable with the exception of confusion (abbreviated mental test score 7/10). Initial investigations showed low serum sodium of 122 mmol/litre with normal potassium, renal and thyroid functions. His liver functions were abnormal with aspartate transferase of 76 IU/litre and alkaline phosphatase 286 U/litre. Chest X-ray showed bilateral non-specific reticular changes suggestive of infection. Two sets of blood cultures showed no growth after 72 hours. Urine tests for legionella and pneumoc...