Page:Tropical Diseases.djvu/936

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880
DISEASES OF THE SKIN
[CHAP.

a lenticular shape. Some are bean-shaped and flat. To study their structure it is necessary to boil them first in a solution of caustic potash. The hyphal threads are large and closely set, but without any cementing substance between them. The periphery of the grain contains numerous large chlamydospores with thick wall and full of protoplasm.

The grains of Indiella mansoni are always numerous within the inflammatory tissue. The latter is brownish and is not surrounded by a well-marked sheath of connective tissue as in other mycetomas. It contains numerous polynuclear cells, a few lymphocytes, and some macrophages.

vii. REYNIER'S WHITE MYCETOMA

Caused by Indiella reynieri, Brumpt, 1906. This form was found in Paris by Keynier.

The grains may attain 1 mm. in diameter; they are soft, white, and consist of a coiled-up strand, which gives them a peculiar appearance resembling the excrement of earthworms. They are made up of a dense felting of hyphal threads, the peripheral branches of which usually terminate in chlamydospores divided into two or three compartments. The hyphæ are bound by a scanty cement, which is easily dissolved out by boiling in caustic potash.

viii BOUFFARD'S WHITE MYCETOMA

Caused by Indiella somaliensis, Brumpt, 1906. This form is perhaps even more common in India than Vincent's white mycetoma. Bouffard has found it twice in Somaliland.

{{smaller|Indiella somaliensis is a most destructive fungus. In a foot examined by Brumpt all the muscles, tendons, and bones had been replaced by sclerosed tissues more or less homogeneous and presenting numerous sinuses full of yellowish grains clustered together like fish-roe, and many small inflammatory nodules containing one or more grains.

The grains vary in colour from white to reddish yellow; they are small, smooth, and attain on an average about 1 mm. in diameter. They are spherical when single, but polyhedral from reciprocal pressure when clustered in masses. The parasite in its earliest stage is always found in a giant cell, showing as an irregular mass which stains more deeply than the enclosing cell. Usually several infected cells coalesce; the grain which results is surrounded by an amorphous layer produced by the destruction of the elements which form its substratum. The grains are not enclosed within nodules, as is the rule in certain mycetomas, but spread exactly like those of actinomycosis.

In the amorphous zone of cellular detritus Brumpt found a discomyces which seems to live symbiotically with Indiella somaliensis. In attempts at culture BoufFard found that this discomyces was the only organism that grew. Other investigators— Boyce, Vincent, Musgrave and Clegg, etc.— have cultivated a streptothrix from the white variety, differing from the