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*Healing lesions are alopecic, lichenified plaques.
*Healing lesions are alopecic, lichenified plaques.
*Lesions may also occur on the flank, udder, teats, face and neck.
*Lesions may also occur on the flank, udder, teats, face and neck.
===Histopathology===
*Adult parasites occur within cystic diverticula of hair follicles or free within the adjacent dermis.
**Parasites may have lateral cords and lateral cuticular projections.
**The thick intestine is distinctive.
**Microfilariae within uteri is the key feature.
***Microfilariae also occur free within the dermis, in dermal lymphatics, or in the surface exudate.
*There is little dermal reaction to adults in cystic hair follicles, but their presence within the dermis elicits eosinophilic and mononuclear inflammation.
===Differential diagnosis===
# Pelodera strongyloides: Rhabditid parasite, adults 1-1.5mm long, found in follicles; uteri contain eggs, not microfilaria.
# Dermatophytosis (Trichophyton verrucosum is most common)
# Mange (Chorioptes bovis)
# Fly bite dermatitis
# Contact dermatitis
# Zn-responsive dermatitis
# Other subcutaneous filarid parasites:
## Parafilaria bovicola (adult worms 30-70mm long, found coiled in nodules in subcutaneous and intramuscular connective tissues; not seen in US)
##Onchocerca gutterosa (adult worms 60mm long, found in nuchal ligament and subcutaneous connective tissues).
==Stephanofilaria assamensis==
==Stephanofilaria assamensis==