Mikihisa Yajima

Malignant melanoma of the buttock presenting as a Buruli ulcer.

We report an unusual case of malignant melanoma clinically diagnosed as Buruli ulcer, that arose in a 13‐year‐old boy and presented as an ulcerated, fungating 2 cm mass on the right buttock. The tumor showed the histology and immunohistology of a malignant melanoma. We present this interesting case of malignant melanoma of soft tissue, arising in an unusual location of the body. The tumor presented with clinical features of Buruli ulcer in an area endemic for this disease as well as other tropical ulcerations. Neoplasms, including melanoma, should be considered in the differential diagnosis of Buruli ulcer in endemic areas.

Buruli and the ulcers under the tropics.

Buruli ulcer, caused by Mycobacterium ulcerans is considered the third most prevalent mycobacteriosis after Tuberculosis and Leprosy. A largely neglected disease, it represents a serious treat to public health in poor and remote rural areas of endemic countries. Emerging since the eighties as an important cause of human suffering, the disease has been reported or suspected in more than 30 countries in the world. Although Africa remains the most affected region, Asia bears as well some endemic regions like Australia, India and Malaysia whether Buruli ulcer is an emerging or re-emerging remains subject of controversy. But, that Buruli ulcer is a neglected disease fits perfectly in the WHO definition of Neglected diseases. Although Buruli ulcer can prove extensively damaging to the skin, its awareness is very limited in the medical community as well as in the general public. This results in its underrecognition and thus its under-reporting. Its under-diagnosis or most frightening, its misdiagnosis can lead to life threatening consequences. We report here a series of 96 specimens of skin biopsy, obtained from the Agroyesum Catholic Mission Hospital in the Ashanti district of Ghana. Thirty % of the specimen in the series proved to be misdiagnosed lesions, other than Buruli ulcer. Among these, 1/3 were malignant lesions ranging from fibrosarcoma to malignant melanoma. The remaining were inflammatory tumorus conditions. The aim of the present study is to emphasize that Buruli ulcer can lead to confusion with the wide spectrum of tropical both parasitosis and infectious conditions that can mimic its different clinical presentation.

ハンセン病(LLs)に生じた脂漏性角化症の表皮内菌球についての検討

A 67-year-old patient has had exanthema in the lower right limb since 51 years ago (16 years old at onset), which underwent repeated remission and recurrence. At present, he has bilateral symmetrical widespread infiltrating exanthema and asymmetrical marked neuralhypertrophy, and has been diagnosed typical LLs (His father had the same disease). The exanthema recurred several years ago, and the patient is being treated for Hansens disease. He had a dark brown flat elevation with a rough surface and the size of a small finger tip in his right abdominal skin for approximately 20 years. A biopsy was performed, and the specimen was fixed in 10% formalin and paraffin sections were prepared for histopathologic examination. A part of the specimen was processed forscanning electron microscopic examination. Seborrheic keratosis was diagnosed by H & E staining. Acid-fast (FITE) staining, immunohistochemical staining (keratin, S-100 protein, anti-PGL antibody and anti-BCG antibody) and scanning electron microscopy revealed the presence of bacteria (M. leprae) in the dermal foam cells, the matrix with a banded structure and the squamous epithelial cells which normally lack phagocytosis function. Compared to the basal cells of normal epidermis, the basal cells located adjacent to the dermis affected with seborrheic keratosis showed increased proliferation and more marked characteristics of a germinative cell. The degree of differentiation of the basal cells appeared regressed, and they probably possessed augmented phagocytic activity. The phagocytosed bacteria were probably carried by the epidermal cell cycle toward the surface layer. However, bacteria could not be found in the stratum corneum, probably due to an association with the lysosome.