Nephrogenic metaplasia

Nephrogenic metaplasia (also known as nephrogenic adenoma) is a benign condition of the urinary tract that is often associated with chronic irritation or trauma. It is characterized by the proliferation of tubular structures resembling renal tubules.

Etiology

The exact cause of nephrogenic metaplasia is unknown, but it is often associated with a history of urinary tract irritation or trauma. This can include previous surgery, urinary tract infections, bladder stones, or indwelling catheters. It has also been reported in association with bladder cancer and after renal transplantation.

Clinical Features

Patients with nephrogenic metaplasia may present with a variety of symptoms, including hematuria (blood in the urine), dysuria (painful urination), and urinary frequency. However, many patients are asymptomatic and the condition is discovered incidentally during investigations for other urinary tract conditions.

Diagnosis

The diagnosis of nephrogenic metaplasia is made based on histological examination of a biopsy specimen. The characteristic finding is the presence of tubular structures that resemble renal tubules, often with a surrounding inflammatory infiltrate. Immunohistochemical staining can be helpful in confirming the diagnosis.

Treatment

Treatment of nephrogenic metaplasia is primarily aimed at managing the underlying cause of urinary tract irritation or trauma. This may involve treating urinary tract infections, removing bladder stones, or changing indwelling catheters. In some cases, surgical resection of the lesion may be necessary.

Prognosis

Nephrogenic metaplasia is a benign condition and does not have any malignant potential. However, it can cause significant morbidity due to its associated symptoms and the need for ongoing management of the underlying cause of urinary tract irritation or trauma.