Fatal Cutaneous and Visceral Infection in a Rottweiler Dog Associated with a Sarcocystis-Like Protozoon

Abstract

A 10-month-old male Rottweiler dog from Ottawa, Illinois, had persistent diarrhea for 2 months. After the diarrhea stopped, the dog developed multiple cutaneous abscesses all over its body, particularly in the hind limbs. The limbs were swollen, hot, and painful. A skin biopsy was fixed in 10% formalin solution. The dog died, and the carcass was frozen until necropsy. No other history was available.Portions of liver, unspecified lymph node, lungs, kidney, and skin from the frozen-thawed carcass were fixed in 10% formalin solution. Paraffin-embedded sections of tissues were cut at 5 pm and stained with hematoxylin and eosin (HE). Paraffin-embedded sections from the biopsy specimens of skin were deparaffinized and reacted with Toxoplasma gondii antiserum and Neospora caninum antiserum with an avidinbiotin complex (ABC) immunohistochemical staining method? To further identify the protozoon, biopsy specimens of skin were deparaffinized and processed for transmission electronmicroscopy.Severe necrotizing fibrinosuppurative dermatitis was evident in the sections of skin (Figs. 1, 2). Numerous neutrophils, fewer eosinophils and macrophages, and abundant edema and fibrin expanded extensive areas of deep dermis and occasionally extended into superficial dermis and subcutaneous fat. Multifocal areas of dermal connective tissue and rare hair follicles were necrotic. Capillaries and venules were markedly congested. Many of them contained fibrin thrombi, and the walls of some were disrupted and infiltrated by neutrophils. Hemorrhage had occurred in some areas. A focally extensive area of epidermal necrosis and ulceration overlain by a fibrinohemorrhagic crust was present.A 1-cm-diameter focus of necrosis and fibrinosuppurative inflammation was present in the lung. Alveolar septa in this area were necrotic. Numerous neutrophils, fewer macrophages, and abundant fibrin filled alveoli and expanded re-

Acute Hepatic Sarcocystosis in a Chinchilla

“…The type of host reactions in S. canis and conventional species of Sarcocystis also differs. Sarcocystis canis and S. neurona typically cause necrosis, whereas lesions in conventional Sarcocystis species are generally inflammatory 5,6 The lesions in the liver of this chinchilla were identical to those reported in a Rottweiler dog. 2 Sarcocystis species have a 2-host life cycle.…”

“…The reagents and controls were the same as used previously. 6,14 Histologically, the liver contained random, variably sized In the article "Experimental rayless goldenrod (Isocoma pluriflora) toxicosis in goats" by Bryan L. Stegelmeier et al, the published mean body weight and the means and statistics of serum biochemistries were carried out on groups of 4 animals, not 3, as described in the Material and Methods section. The additional animal in each group was part of an auxiliary physiologic study and though the animals were dosed and treated the same, they were not necropsied and were not included in the histologic study.…”

An update on Sarcocystis neurona infections in animals and equine protozoal myeloencephalitis (EPM)

“…Hosts in which mature sarcocysts have been demonstrated are the intermediate hosts. Laboratory-raised opossums excreted sporocysts after feeding naturally infected skunk, raccoon, sea otter or armadillo muscle (Cheadle et al, 2001c; Cheadle et al, 2001d; Tanhauser et al, 2001; Dubey et al, Dubey et al, 2001b, Dubey et al, 2001c), indicating that they are proven intermediate hosts of S. neurona . Mansfield et al (2008) reported brown-headed cowbirds as intermediate host for S. neurona but this finding needs confirmation.…”

“…Giemsa stain. ( A ) Smear from a pustular dermal ulcer from a Rottweiler dog reported by Dubey et al (1991b). Note several intensely stained schizonts (arrows) among leukocytes and RBC.…”

Cutaneous Neosporosis in Two Adult Dogs on Chronic Immunosuppressive Therapy

“…Confirmed cases of dermatitis have been associated with Caryospora sp. 6 and S. canis 14 23 Amastigotes containing kinetoplasts are pathognomonic for Leishmania. Toxoplasma gondii can infect virtually all body tissues; however, there are no reported cases of cutaneous toxoplasmosis in dogs.…”