Mycobacterial soft tissue infections in North Queensland.

BACKGROUND: Mycobacterial soft tissue infections are a heterogeneous group of infections that usually require a variety of therapeutic methods for cure. North Queensland has an environment, which predisposes to several such infections. The aim of this study was to assess the incidence and epidemiology of mycobacterial soft tissue infections in North Queensland and to review surgical and non-surgical interventions in these conditions. METHODS: This study was a retrospective review of all patients with a proven mycobacterial soft tissue infection, seen between 1997 and 2005 in a tertiary referral centre in North Queensland. RESULTS: In total, 34 patients were identified. The most common causative organisms were Mycobacterium fortuitum (44%), M. ulcerans (17.6%) and M. abscessus (11.8%). The risk factors identified were the male sex, lower-limb involvement and preceding trauma including surgery. Twenty-four (70.6%) patients had surgical excision or debridement with a variety of adjuvant antimicrobial therapies. There were eight (23.5%) local recurrences. CONCLUSION: The optimal management of soft tissue mycobacterial infections includes early microbiological identification based on tissue biopsy, appropriate combination antimicrobial therapy and early wide surgical excision where appropriate. North Queensland has a unique environment, which may predispose to these infections. An awareness of this is essential to surgical practice in the region.

A case of suboccipital lump with a rare and unexpected diagnosis of apocrine cystadenoma.

INTRODUCTION: Cystadenoma of apocrine origin is a tumour of the sweat gland that is benign in nature. Classification of this pathology is based upon histological characteristics plus histochemical analysis. Prevalence of cystadenoma has been suggested to be quite rare, in the region of 1 in 1000 of subcutaneous biopsies observed. PRESENTATION OF CASE: We present a case of a 40 year old man referred by his GP with a suboccipital lump, present for some years. On examination the lump was approximately 4-5cm in diameter and an unusual punctum was present. The patient proceeded to an excision of the lesion and the gross specimen showed characteristics of a multiloculated cyst, measuring some 5cm×3.5cm. Histopathology of the tumour revealed an apocrine cystadenoma; there were no features suggestive of malignancy. DISCUSSION: Previous classification of cystadenoma via histological and immunohistochemical method; has revealed only two distinct entities and the term hydrocystoma was often used in place of cystadenoma. More recent studies have suggested that a third type can be identified via immunohistochemical analysis. This third type; apocrine hydrocystoma, reveals that those previously defined as eccrine in origin may also be related to the apocrine ducts. CONCLUSION: Apocrine cystadenoma remains a benign pathology and treatment should be focussed on excision, without need for further intervention. Apocrine cystadenoma remains a relatively rare pathology, though one which should not recur if adequate treatment is given.