Pelodera Dermatitis

Pelodera dermatitis is rare skin worm infestation that causes a short-term skin infection. The condition is caused when larvae of roundworms known as Pelodera strongyloides invades the skin. These larvae are widespread in decaying organic matter (such as damp hay or rice hulls) and on or near the surface of moist soil. They are only occasionally parasitic.

Signs of Pelodera Dermatitis

Lesions associated with this infestation are typically present in areas of the skin that contact the ground, such as feet, legs, lower chest and abdomen, and tail. Alopecia, red skin and papules are initially present. Later crusts, scales and secondary bacterial infection may occur. In chronic cases thickening and hyperpigmentation of the skin is usually present. Itch can vary from mild to intense.

Diagnosis of Pelodera Dermatitis

Diagnosis Diagnosis is made based on the history and physical findings. Deep skin scrapings will, in most cases, demonstrate the small motile nematode larvae. Skin biopsy can also reveal nematode segments within hair follicles and within inflammatory reactions in underneath the skin.

Treatment of Pelodera Dermatitis

Treatment is effective and simple. Change the animal's environment, which is harboring the larvae. After cleaning the environment, spray all ground surfaces with malathion (one ounce of 57-59% malathion per gallon of water). Animals should be bathed with a medicated shampoo to remove the scales and crusts.

The infestation is self-limited and resolves spontaneously after the animals are removed from the source of contamination. Appropriate antibiotic should be used if secondary pus-forming infection develops. Prednisone can be given for a few days if itchiness (pruritus) is intense.

References:
1. Scott, Miller, Griffin: Parasitic Skin Diseases. In: Small Animal Dermatology, 5th ed., W.B. Saunders, Philadelphia, PA, 1995
2. Scott, D.W.. Parasitic Diseases. In: Large Animal Dermatology. 1st ed., W.B. Saunders, Philadelphia, PA