Malakoplakia

Overview

Malakoplakia is a rare inflammatory condition which makes its presence known as a papule, plaque or ulceration that usually affects the genitourinary tract. However, it may also be associated with other bodily organs. It was initially described in the early 1900s as soft yellowish plaques found on the mucosa of the urinary bladder. Microscopically it is characterized by the presence of foamy histiocytes with basophilic inclusions called Michaelis-Gutmann bodies.

Symptoms

* Raised lesions in the colon * Diarrhea * Gastrointestinal symptoms * Asymptomatic * Fever

Diagnosis

The differential diagnosis of cutaneous malakoplakia includes other infectious, neoplastic, and reactive/reparative processes. Infectious processes to consider include tuberculosis, Whipple disease, lepromatous leprosy, fungus (Cryptococcus), and parasites (leishmaniasis). Special stains for microorganisms and consideration for tissue culture is necessary. Reactive and neoplastic processes include Langerhans cell histiocytosis, fibrous histiocytoma, lymphoma, granular cell tumor, xanthoma, foreign body granuloma, hemophagocytic syndromes, and sarcoidosis

Prognosis

The course of malakoplakia is somewhat variable with occasional cases recurring, spreading, and rarely leading to death. No deaths to our knowledge have been directly associated with cutaneous malakoplakia.

Treatment

An 81% cure rate in patients undergoing surgery with or without antibiotic therapy has been reported in a literature review of malakoplakia. In patients treated with antibiotics, the highest cure rate was seen in patients treated with quinolones and in those receiving sulfamethoxazole-trimethoprim, which is believed to be related to penetration and concentration of these antibiotics within macrophages. Other therapies used with some success include discontinuation of immunosuppressants and bethanechol therapy. Greater than 90% of the cutaneous malakoplakia cases with follow-up information (25 cases) had complete resolution with treatment. Treatment consisted of a combination of surgical manipulation with or without antibiotic therapy or, in the cases of organ transplantation, tapering and discontinuation of immunosuppressive therapy.