A Case of Bladder Melanosis Associated with Recurrent Urinary Tract Infections

Abstract

Bladder melanosis is a very rare clinical entity that has reportedly been associated with a wide variety of urinary symptoms. Reports also exist of an association with bladder malignancy. We describe a case with a 58-year-old man under urological investigation following 2 urinary tract infections. Several flat, blackened areas within the bladder were observed at cystoscopy, which histology revealed was due to increased melanin deposits within bladder urothelial cells; i.e., melanosis. This finding is of uncertain significance, and regular cystoscopic followup was thought to be prudent. At 3 months, appearances were unchanged; however, at 6 months, the bladder's appearance was entirely normal with resolved changes of melanosis.

Melanosis of the Bladder: Possible Pathogenetic Mechanisms

“…The melanosis could perhaps have been caused by her UTIs. Such an association has been reported previously [ 8 , 12 ].…”

Lipofuscin pigmentation (so called “melanosis”) of the bladder

“…The urine cytologic findings in previously reported cases were poorly documented; they were not mentioned at all in 15 cases, were reported as “negative” or “unremarkable” in eight cases, and “atypical” in a single case . In the remaining five cases, the cells containing pigment were seen .…”

Melanosis of bladder: A rare entity

“…There is also a large diverticulum associated with the melanosis along with UTI. Only one other case report was found in our search which showed a concurrent UTI and diverticulum associated with melanosis vesicae 5 …”

“…However, it can be mistaken for primary or metastatic melanoma of the bladder wall. Therefore, correct diagnosis of the lesion can save the patient from potential over-treatment 5 …”