Oral Acidification with l-Methionine as a Noninvasive Treatment for Encrusted Uropathy

Encrusted uropathy (EU) is a rare disease caused by urea-splitting bacteria, most commonly Corynebacterium urealyticum, whose incidence is increasing. Standard treatment is based on pathogen-directed antibiotic therapy, urinary diversion, bladder instillations, and surgical resection of urinary calcifications. We present the case of a 60-year-old man with symptomatic bilateral encrusted pyelitis and cystitis with acute renal failure. We initially treated the patient with antibiotic therapy, urinary diversion, and oral acidification with acetohydroxamic acid, achieving negative urinary cultures. Because of the persistence of encrusted pyelitis, the patient was discharged on oral l-methionine 500 mg bid and 12 months later the encrustations had almost disappeared. Finally, we performed right retrograde intrarenal surgery to remove a persistent small calcification. Oral urinary acidification with l-methionine is a valid treatment for urinary encrustations in EU, with no complications reported. Complete resolution of the calcifications may be achieved without the need for invasive processes and unnecessary manipulation of the urinary system.