Mammary duct fistulae: Classification and management

Background: The aim of the present study was to review the management of mammary duct fistulae and propose a classification that could be useful in planning the management of mammary duct fistulae. Methods: Sixteen women presented with a mammary duct fistula, two of whom had two fistulae. The data analysed included age, smoking habit, previous abscesses, nipple abnormalities, imaging, culture, operative technique and histopathological findings. Results: The average follow up was 28 months, the mean age was 36.5 years and two women were heavy smokers. Nipple abnormalities were found in five (32%) patients, the average number of abscesses before the presentation was 1.8 and Staphylococcus coagulase negative predominated the culture. Eleven (69%) patients underwent total excision of the ductal system and fistulous tract using a technique modified by the author. Five patients were offered conservative treatment; however, one of the patients refused surgical treatment, but was still followed up in the present study. Histopathological results revealed periductal mastitis in 10 patients, idiopathic granulomatous mastitis in five patients and tuberculous mastitis in one patient. Conclusion: Deep mammary duct fistulae are directly related to a diseased ductal system and should be differentiated from superficial fistulae, which result from the infection of the subepidermal mammary glands. Deep fistulae that result from periductal mastitis should be treated by total excision of the ductal system in conjunction with the fistulous tract under antibiotics to ensure the lowest rate of recurrence. The technique used in the present study resulted in negligible morbidity and good cosmetic appearance. A trial of conservative treatment should be recommended for fistulae resulting from idiopathic granulomatous mastitis; however, further studies are required to establish the best treatment.