Rebeca Pinca, MD,1 Joseph M. Lam, MD, FRCPC,2

1Department of Dermatology & Skin Science, University of British Columbia, BC.
2Clinical Assistant Professor, Department of Pediatrics and Dermatology, University of British Columbia, BC.


Abstract: Dermatology is a visual specialty, yet palpation can also play an important diagnostic role. We present five dermatologic diagnoses that can be made at point of care by palpation or physical manoeuvres, potentially reducing unnecessary investigations, such as biopsies.
Key Words: Dermatofibromas, pilomatricomas, mastocytomas, spider angiomas, terra firma-forme dermatitis.
Dermatofibromas and pilomatricomas are benign papulonodular lesions that can be differentiated by the dimple sign, and the teeter-totter sign or tent sign, respectively.
Solitary mastocytomas can be diagnosed by Darier sign, whereby rubbing of the lesion causes a wheal and pruritus.
Spider angiomas can be diagnosed by diascopy, which involves the application of gentle downward pressure with a glass slide on the skin, resulting in blanching of the telangiectasia.
Terra firma-forme dermatitis is a benign discoloration that can be diagnosed, and treated, by gentle rubbing with isopropyl alcohol.
These dermatologic physical examination manoeuvres are quick, cost-effective, point-of-care diagnostic tools.
If in doubt, do not hesitate to biopsy lesions that appear suspicious.
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