Selected monographs on dermatology / P.G. Unna [and others].

Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Selected monographs on dermatology / P.G. Unna [and others]. Source: Wellcome Collection.

    479/636 (page 461)
    Diagnosis.—Little difficulty should be experienced in the diagnosis of the chloral eruption. From measles and scarla- tina it may be differentiated by the absence of fever, catar- rhal symptoms, characteristic throat and tongue, &C1 It may be confounded with the erythema produced by bella- donna, copaiba, and quinine respectively. The belladonna rash is almost always accompanied with mydriasis, dryness of the fauces, &c. The chloral rash has special features of its own, such as the absence of subjective sensations, its, liability to development after the ingestion of alcohol or a full meal, which serve to distinguish it.2 The peculiar odour exhaled in copaibic eruptions is always of diagnostic value. Tests for Chloral. If chloral is to be detected in urine, the latter is mixed with about one fourth volume of alcohol, then rendered neutral, if necessary, by either carbonate of magnesium or tartaric acid, as the case may be, and distilled until only a syrupy residue remains. The distillate now contains the chloral. This is recognised by its products of decomposi- tion, viz. chloroform and formate of ammonium (or of other alkali), when the solution is treated with an alkali. The distillate is, therefore, rendered alkaline with soda, and again distilled. The new distillate will contain the chloro- form, which is identified as shown below. The formate is recognised in the residue by the fact that the latter promptly reduces nitrate of silver to a metallic state—a portion of the residue, when heated in a test-tube with solution of nitrate of silver, producing a brilliant metallic mirror. 1 It has already been pointed out that fever and a congested throat may occasionally be present, and there may be running from the eyes, with con- junctival congestion.—T. C. F. 2 Itching is present occasionally, even to a considerable degree, e.g. Husband's case. The sites attacked and the order of evolution from the face, neck, chest, to the great articulations are of some importance. Further, there is the evanescence of the rash and its reappearance when the chloral is readministered, and finally the dyspnoea, palpitation, &c, usually provoked. Bouju failed to confirm Barbillion's observation that the breath acquired a special ethereal odour. Watson and Hutchinson record cases in which the eruption was confined to the hands.—T. C. F.