Which parasite causes alopecia on ventral abdomen and elbows?

Which parasite causes alopecia on ventral abdomen and elbows?

• A. Ringworm
• B. Demodex
• C. Scabies
• D. Fleas

Answer: (C)

The distribution of lesions is a big clue. Scabies causes intense itching and self-trauma, and the mites burrow into the skin in areas that are prone to scratching and rubbing, so you often see hair loss with crusting on ventral surfaces like the abdomen and elbows. This ventral/ellbow pattern is a classic sign of sarcoptic mange in dogs, where the itching drives the alopecia there. Ringworm can cause hair loss as well, but it usually presents as circular patches with scaling and broken hairs rather than a predilection for ventral abdomen and elbows. Demodex typically causes alopecia around the face and front legs, especially in puppies, and fleas tend to produce hair loss around the tail base and hindquarters from flea bite reactions. If scabies is suspected, diagnostic skin scrapings can reveal mites, eggs, or fecal pellets, and effective treatment targets the mites and the itching.

The distribution of lesions is a big clue. Scabies causes intense itching and self-trauma, and the mites burrow into the skin in areas that are prone to scratching and rubbing, so you often see hair loss with crusting on ventral surfaces like the abdomen and elbows. This ventral/ellbow pattern is a classic sign of sarcoptic mange in dogs, where the itching drives the alopecia there.

Ringworm can cause hair loss as well, but it usually presents as circular patches with scaling and broken hairs rather than a predilection for ventral abdomen and elbows. Demodex typically causes alopecia around the face and front legs, especially in puppies, and fleas tend to produce hair loss around the tail base and hindquarters from flea bite reactions.

If scabies is suspected, diagnostic skin scrapings can reveal mites, eggs, or fecal pellets, and effective treatment targets the mites and the itching.