In the abdominal cavity, particularly in sows, actinomycotic lesions occur as little masses varying in size between that of a pea and that of a haricot bean, attached to the epiploon and peritoneum and filled with pus containing mycosic grains.
Diagnosis. Actinomycosis is usually easy to recognise, both on account of the special character of the lesions and the presence of the little grains formed by the parasite. The practitioner will rarely fail to recognise at once the signs of actinomycosis of the jaw, but actinomycosis of the tongue is more apt to be mistaken for deep-seated sclerosing glossitis, although a careful examination will always enable the different symptoms to be distinguished.
It is otherwise with regard to growths in the pharynx and œsophagus, for, until after removal, simple polypi cannot be distinguished from actinomycotic growths. In such cases the administration of iodide of potassium affords valuable indications.
The prognosis is grave, whatever the clinical form of the disease. Important advances, it is true, have lately been made, and the iodide of potassium treatment is of great value, but too much must not be expected of it, and its benefits have certainly been exaggerated. Clinical experience suffices to prove that only actinomycosis of soft tissues can be cured by drugs, bony lesions being amenable only to medical and surgical treatment combined. Even combined treatment is often unsuccessful.
Treatment. Thomassen in 1885 first explained the favourable action of iodide of potassium on actinomycotic growths, and Nocard in 1892 again directed public attention to the advantages attending the use of this drug both in man and the lower animals. As too frequently happens, however, the benefits of this treatment have been exaggerated, and iodide of potassium has been held out as a specific even against lesions in bone. With very few exceptions this is incorrect, and, as Moussu has shown, when the disease affects bone tissue it only yields to mixed treatment.
The treatment of actinomycosis may therefore be considered under two heads.
Firstly, the treatment of actinomycosis of soft tissues; and, secondly, that of bone.
Actinomycosis of soft tissues, muscle, skin, lymphatics, serous membranes, etc., comprises the most common forms of actinomycosis, viz., those of the tongue, pharynx, parotid glands, neck, etc.
The second form comprises actinomycosis of the lower jaw (molar region), the upper jaw, region of the incisors, etc.
Iodide of potassium in daily doses of from 2 to 3 drachms is almost a specific in dealing with the first form of disease.