Phrynoderma is hypkeratotic disorder that is a skin manifestation of malnutrition.

Phryno is Greek for toad. Phrynoderma indicates a toad-like skin.


The key feature is hyperkeratotic folliculitis, especially on extensor surfaces. The gross appearance consists of diffuse keratotic papules. On biopsy the papules are dilated hair follicles with keratin plugs.


Phrynoderma is often present along with other signs of malnutrition (weakness, fatigue, night blindness, cheilitis, glossitis, etc.


Risk factors:

(1) a disorder of diet

(2) a disorder of absorption (malabsorption, intestinal bypass surgery, short bowel)


Nutrients associated with phrynoderma include:

(1) vitamin A

(2) vitamin E

(3) various B vitamins

(4) essential fatty acids (EFA)

(5) micronutrients

(6) various combinations of the above

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