Malacoplakia of the urinary bladder: case report and systematic review

Introduction: Malacoplakia is a rare chronic inflammatory disease that commonly affects the urinary bladder, and it is characterized by the presence of large cells containing vacuoles known as Michaelis-Gutmann bodies. Case report: A 79-year-old woman was admitted to the emergency department a poorly defined with symptoms of fever, dysuria, hematuria, and pain and swelling in her right knee. Microbiological studies indicated the presence of Escherichia coli in blood cultures, urine cultures, and synovial fluid cultures of the right knee. A computed tomography scan revealed nonspecific bladder thickening, which was further confirmed by a cystoscopy. A poorly defined lesion in the trigone was resected, and subsequent pathological examination revealed the presence of malacoplakia without evidence of malignancy. The patient was treated with antibiotic therapy, and the hematuria eventually resolved. Systematic review: We conducted a comprehensive search in the Medline, EMBASE, and WoS databases from January 1, 1993, to January 1, 2023, for articles that focused on Malacoplakia, involved human subjects. Were included 32 articles reporting on 35 cases of urinary bladder malacoplakia. The majority of those diagnosed with bladder malacoplakia were women under the age of 50, with recurrent urinary tract infections and immunosuppressive conditions as frequent comorbidities. Positive cultures showed Escherichia coli (E. coli) in 72% of cases. Successful outcomes were achieved in 26 cases (74.3%). Discussion: Malacoplakia is triggered by an inadequate immune system response to lower urinary tract infections. Diagnosis requires prior biopsies before resection or more aggressive treatments. Appropriate treatment of urinary tract infections with antibiotics targeted at gram-negative bacteria is essential for treating malacoplakia.