DIAGNOSrS 



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The characteristics of the disease are:- — 



1. Acute dermatitis appearing suddenly and often without 

 apparent cause in a previously healthy person. 



2. The history of the association with some plant by handling 

 or being affected by the odour, or even of being in the neighbourhood 

 thereof. 



3. There may be history of previous similar attacks when in the 

 vicinity of the suspected plant. 



4. The rapid recovery on removal from the causal plant. 



5. The return of the symptoms when again exposed to the plant. 

 The differential diagnosis has to be made from other forms of 



dermatitis, which can usually be done by the history and by finding 

 the causal plant, but this will not help with certain forms of acarine 

 dermatitis when the mite infests the plant. 



In such a case the only possible method of diagnosis is to examine 

 the plant and the patient carefully, so as to exclude the presence 

 of these insects, and to reproduce the disease by means of a plant 

 found to be quite free from mites. 



Treatment. — The essential feature of the treatment is to remove the 

 plant from the patient or the patient from the plant, whichever maybe 

 most convenient. The next point is to remove all irritating substances 

 by copious bathing of the whole body in water, and in some cases to 

 recleanse the affected area with alcoholic solutions. Lastly, soothing 

 lotions such as calamine lotion should be applied to the inflamed area. 



Strickler has tried in certain types the injection of minute doses of the 

 poisonous principles extracted with absolute alcohol. 



Prophylaxis. — When the patient knows that he is susceptible to 

 the influence of a given plant, care should be taken to avoid it. 



Varieties. — ^Dermatitis venenata may be divided into several 

 groups as follows :— 



I. The Rhus Group. — Plants in which the poisonous principle is 



contained in a clear watery fluid. 

 II. The Euphorbia Group. — Plants in which the poisonous principle 

 is contained in a thick milky fluid. 



III. The Vrtica Group. — Plants in which the poisonous principle is 



contained in fluid in special hairs. 



IV. The Tectona Group.- — Plants and dried hard woods, the dust 



of which contains the poisonous principle. 

 V. The Rue Group. — Plants in which the poisonous principle is 

 apparently volatile, but acts mainly when the plants are 

 ^ handled. 



VI. Buffalo Bean Group. — Plants in which the causal agent is 

 innumerable minute hairs which penetrate into the skin. 

 VII. The Little-Known Group. — This is a group containing plants 

 which apparently cause dermatitis venenata, but about 

 which information is very defective. 

 VIII. The Doubtful Group. — This contains plants |Which probably 

 do not produce dermatitis venenata, but perhaps harbour 

 a mite which may be the causal agent. 



