Neospora caninumassociated with septic peritonitis in an adult dog

Abstract

A 7-year-old, male neutered Rhodesian Ridgeback dog was referred to the University of California-Davis Veterinary Medical Teaching Hospital with a 4-month history of peritonitis and episodic abdominal discomfort, lethargy, and weakness. Marked abdominal distension with a prominent fluid wave was noted on physical examination. Cytologic analysis of the abdominal fluid indicated a septic exudate with mixed bacteria and many protozoal zoites. Differentials for the identity of the protozoal zoites included Toxoplasma gondii, Sarcocystis neurona, and Neospora caninum. Indirect latex agglutination antigen testing, standard indirect fluorescent antibody testing, and PCR analysis were performed to identify the zoites. The dog's serum antibody titer for N caninum tachyzoites was 1:20,480, known polysera to N caninum reacted against zoites in the abdominal fluid, and PCR analysis of the abdominal fluid was positive for the presence of a known gene of N caninum. Based on the morphologic, immunologic, and molecular findings, the zoites were identified as N caninum. It remains unclear how the tachyzoites gained access to the peritoneal cavity. To the authors' knowledge, there are no reports of free N caninum in abdominal fluid of any species.

Neosporosis in animals—The last five years

“…A wide array of clinical signs have been reported in older dogs, often on immunosuppressive therapy (Holmberg et al, 2006;Crookshanks et al, 2007;Fry et al, 2009;Galgut et al, 2010;Garosi et al, 2010). Treatment of clinical neosprosis with currently available drugs, including clindamycin, is only partially effective.…”

Infectious Hepatopathies in Dogs and Cats

“…103 Serology and muscle biopsy often provide a diagnosis, although tachyzoites may be detected in other parasitized tissue or body fluid. 110 Sarcocystis canis is an apicomplexan protozoan with no particular geographic distribution. Infection results in disseminated disease, including protozoal hepatitis.…”

Neosporosis presenting as temporal muscle atrophy in a dog

“…Consideration of a protozoal myositis was not made at this time since temporal muscle atrophy has never previously been reported in canine infections with Neospora  species; more typical clinical presentations of neosporosis in adult dogs include muscle weakness and ataxia with paresis or paralysis, pain and cerebellar syndrome (Barber and Trees 1996). Neosporosis can also present with a wide range of non-neurological clinical signs such as pneumonia, septic peritonitis and cutaneous lesions (Greig and others 1995, Ordeix and others 2002, Holmberg and others 2006). …”