Encrusted cystitis is a very rare chronic inflammatory disease of the bladder characterized by precipitation and incrustation of phosphate and ammonium-magnesium salts on the vescical mucosa, caused by urinary infection due to urolithic microorganisms. Corynebacterium urealyticum or Corynebacterium group D2, a multiple antibiotic-resistant urea-splitting bacterium, is the most frequently incriminated aetiology. We report a case of a 57-year-old man affected by systemic erythematosus lupus with a long history of dysuria and suprapubic pain who underwent percutaneous nephrostomy drainage with urethral stenting for lupoid obstructive uropathy. Before the diagnosis of encrusted cystitis by Corynebacterium urealyticum was established, the patient underwent five cystoscopies to remove the plaques and multiple unsuccessful antibiotic treatment courses. Eventually the infection was definitively cured after a two-week course with intramuscular teicoplanin
