General Diagnosis For Skin

     Interpretation of the clinical picture is rendered difficult, for identical manifestations may result from widely different causes. Moreover, the same etiologic factor may give rise to a great diversity of eruptions. However, there is one great advantage in dermatology, namely, that of dealing with an organ that can be seen and felt. Smears and cultures may be readily made for bacteria. By excision and microscopic examination of the lesion, its histopathology can be studied in relation to the clinical appearance, more directly in the skin than elsewhere. A skin disease in its various stages of development can be inspected, palpated, and studied without dependence upon percussion, auscultation, and other indirect diagnostic methods necessary in other branches of medicine.

Importance of the History 

     All facts contributory to a knowledge of the patient's family, his health, occupation, living conditions, the onset and course of the disease, and its response to previous treatment are as pertinent in dermatology as in internal medicine.


     A complete history is of more value than simply serving in the diagnosis. Whereas a history may be superfluous for the diagnosis, or even for the treatment and cure, of easy cases, it is the backbone of treatment in difficult ones. The chronic dermatoses are the most distressing to both the patient and the physician, and form the bulk of dermatologic practice. For the analysis and identification of the cause of the disease, for cognizance of those remedies which have been beneficial or seemed harmful,
for intelligent treatment of the chronic case, a good history is essential, and the degree of improvement that the patient ultimately shows is usually proportionate to the quality of the protocol.

     The history should be systematically arranged, with abbreviations as numerous as clarity permits, all pertinent facts being included, important statements underlined, and irrelevant matters omitted. The wearisome taking of long histories is a hardship, so dispatch and thoroughness in essential data are necessary. 

Examination 

     Examination of the patient should be conducted in a well-lighted room. Daylight is a necessity for successful dermatologic practice, but some eruptions are more clearly visible in ultraviolet light, as in the case of faint macular eruptions, which then become prominent. In tinea capitis the use of ultraviolet light passed through Wood's filter, which is permeable to wavelengths of 3650 A., is of assistance in diagnosis, for the spores become fluorescent in these rays.

     The manner of display of the diseased areas is important. The entire eruption must be seen in order that such factors as distribution and configuration can be studied, as they are of valuable assistance in the recognition of the disease, and for prescription of treatment for the areas involved. Laboratory tests may be necessary to complete the study of the case.