MSD Manual

Please confirm that you are a health care professional

honeypot link

Pelodera Dermatitis in Animals

(Rhabditic dermatitis)


Richard W. Gerhold, Jr.

, DVM, PhD, Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee

Last full review/revision Sep 2019 | Content last modified Oct 2019
Topic Resources

Pelodera is a free-living nematode that can infect the skin of animals. Signs include dermatitis and alopecia, and diagnostic testing includes biopsy of affected regions. Treatment options include various macrocyclic lactones.

Pelodera dermatitis is a rare, nonseasonal, acute dermatosis that results from invasion of the skin by larvae of the free-living saprophytic nematode Pelodera strongyloides. The larvae are ubiquitous in decaying organic matter and on or near the surface of moist soil but are only occasionally parasitic. Exposure to the larvae occurs through direct contact with infested material such as damp, filthy bedding. The larvae may not be able to invade healthy skin; preexisting dermatoses or environmental conditions favoring maceration of the skin, eg, constant exposure to mud or damp bedding, may facilitate invasion. Pelodera dermatitis has been reported in dogs, cows, horses, sheep, guinea pigs, and people.

Typically, lesions are confined to body areas in contact with the infested material, such as the extremities, ventral abdomen and thorax, and perineum. Affected skin is erythematous and partially to completely alopecic, with papules, pustules, crusts, erosions, or ulcerations. Pruritus is usually intense but can be moderate or even absent. Differential diagnoses include demodicosis, canine scabies, dermatophytosis, pyoderma, and other rare cutaneous larval infestations such as hookworm dermatitis, dirofilariasis, dipetalonemiasis, and strongyloidiasis.

Diagnosis is confirmed easily by finding live, motile P strongyloides larvae in skin scrapings of affected areas. The larvae are cylindrical and ~600 × 38 mcm. Histologic examination of skin biopsy specimens reveals larvae in the hair follicles and superficial dermis and usually an inflammatory dermal infiltrate. The larvae are readily cultivated on blood agar plates at 77°F (25°C).

Effective treatment consists primarily of removing and destroying moist, infested bedding material and moving the animal to a clean, dry environment. Usually, spontaneous recovery ensues. It may be desirable to dip or spray the affected animals with an insecticidal preparation at least twice at weekly intervals. Short-term use of corticosteroids may be indicated if pruritus is severe.

For More Information

Also see pet health content regarding Pelodera infection in dogs.

Others also read
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID
Download the Manuals App iOS ANDROID

Test your knowledge

Tumors of the Skin and Soft Tissues
Which of the following diagnostic techniques is LEAST likely to distinguish a benign skin neoplasm from a malignant one? 
Become a Pro at using our website 

Also of Interest

Become a Pro at using our website