Alopecia areata

185 Alopecia areata



Instruction


Examine this patient’s scalp.



Salient features



History




• Young adult (75% of patients are below the age of 40 years)


• History of atopy


• Ask whether there is a family history (25% give a family history)


• Ask the patient whether there are any local symptoms and if the hair loss is cosmetically unacceptable.



Examination




• Well-defined patch of hair loss (Fig. 185.1); short, fractured, exclamation-point hairs may be seen at periphery.


• Regrowing hair in the patch appears as a fine, depigmented downy growth.


image

Fig. 185.1 Alopecia areata.


Proceed as follows:



• Look for patches of hair loss over the eyebrows and beard area


• Examine the nails for fine pitting, transverse lines, dystrophy, fragmentation (anonychorrhexis) and ridging and 20-nail dystrophy (roughened nail surface and brittle free nail edge) (Fig. 185.2)


• Tell the examiner that you would like to:


• look for atopy

• look for other autoimmune conditions including vitiligo (see below).

image

Fig. 185.2 Nail dystrophy.



Diagnosis


This patient has alopecia areata (lesion), which is suspected to be of autoimmune aetiology; it may be cosmetically unacceptable to the patient (functional status).



Advanced-level questions




What are the signs of disease activity?


At the advancing edge, broken hairs that look like exclamation marks indicate active disease. These are very short hairs, tapering and becoming depigmented as the scalp is approached. Plucking reveals such hair to be in the telogen phase.

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Dec 4, 2016 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on Alopecia areata

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