Sabra dermatitis

Plants may induce mechanical irritant dermatitis from delicate hairs called trichromes or hairs with tiny barbs known as glochids. Sabra dermatitis is an irritant dermatitis seen in workers who pick the fruit of prickly pears, which have small barbed bristles (Evans and Schmidt 1980). The awns of barley and other cereal grasses may cause mechanical occupational dermatitis (Evans and Schmidt 1980). Dieffenbachia (Stoner and Rasmussen 1983), daffodil (Narcissus) and hyacinth (Hyacintus) are plants with fine, needle-shaped calcium-oxalate crystals (Evans and Schmidt 1980). The irritation caused by these plants is thought to be induced both by the mechanical action of the oxalate crystal and subsequent penetration of a plant enzyme or toxin into the skin (Epstein 1990). Irritant plants have been reviewed recently by Lovell (1996). Tiny... 

Sabra dermatitis from Opuntia ficus-indica can sometimes resemble scabies [142]. The bunn/s-ears cactus (Opuntia microdasys) a commonly grown ornamental, also has collections of tiny spines called glochids, which are the source of immediate irritation, and sometimes lead to granuloma formation [143]. 

Webster G (1986) Irritant plants in the spurge family (Euphorbiaceae). Clin Dermatol 4 36-45 Shannon J, Sagher F (1956) Sabra dermatitis an occupational dermatitis due to prickly pear handling simulating scabies. Arch Dermatol 74 269-275... 

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