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578
Clinical Snapshot
Clinical Snapshot
#1
Clare L. Deming, DVM
North Jersey Veterinary Emergency Services
Lyndhurst, New Jersey
CASE PRESENTATION
A 6-year-old, castrated, domestic
shorthaired cat was evaluated for
urethral obstruction. After the
patient was stabilized and the
obstruction relieved with the
patient under sedation, urinalysis
was conducted.
1. What is the name of this 65 × 25–µm parasite, and how did the cat become
infected?
2. How significant is this finding in a cat with urethral obstruction but without
crystalluria?
3. What is the recommended treatment?
(See page 580 for answers and explanations.)
COMPENDIUM
October 2007
580
Clinical Snapshot
Clinical Snapshot
#1
ANSWERS & EXPLANATIONS
(Case presentation on page 578)
1. Pearsonema (formerly Capillaria) plica, a
trichurid parasite of cats. This parasite is acquired when a cat (definitive host) ingests an
earthworm (intermediate host) infected with the
first larval stages of the parasite. The first-stage larvae enter the feline host
through the intestines, molt twice, then migrate through the blood to the kidneys. The larvae travel through the ureters and enter the mucosa of the bladder.1 Mature worms can reach 30 to 60 mm in length. Eggs are laid in the
bladder lumen and excreted in the urine. P. plica can infect dogs, cats, foxes,
wolves, and other canids.2
2. The significance is unknown. There is no evidence that Pearsonema infection
contributes to feline lower urinary tract disease, and it is an uncommon finding by urinalysis. In dogs, the infection can be associated with dysuria, stranguria, and pollakiuria.3
3. One source2 recommends treatment with ivermectin at 0.2 mg/kg SC or PO,
repeating the dose if necessary, or fenbendazole at 50 mg/kg PO q24h for 10
to 14 days. This remains controversial because there is no evidence that Pearsonema infection causes significant pathology in cats. Both treatments should
be considered extralabel drug use, and clients should be appropriately informed.
REFERENCES
1. Bowman DD: Georgi’s Parasitology for Veterinarians. Philadelphia, WB Saunders, 1999.
2. University of Pennsylvania: Pearsonema (Capillaria) plica homepage. Accessed August 2007 at
cal.vet.upenn.edu/dxendopar/parasitepages/trichocephalids/c_plica.html.
3. Adams LG, Syme HM: Canine lower urinary tract diseases, in Ettinger SJ, Feldman EC
(eds): Textbook of Veterinary Internal Medicine. St Louis, Elsevier, 2005, p 1872.
COMPENDIUM
October 2007