Disseminated histoplasmosis in cats: 12 cases (1981-1986)

Anemia, weight loss, lethargy, fever, anorexia, and interstitial lung disease were the predominant clinical findings in 12 cats with disseminated histoplasmosis. Some cats were examined because of dysfunction or lesions of bone, eyes, or skin. In most cases, the clinical signs were observed by the owner for 4 weeks or less before seeking veterinary care. Young cats were most commonly affected, with 7 of the 12 cats less than or equal to 1 year old. Identification of Histoplasma organisms in bone marrow aspirates was used to confirm the diagnosis of histoplasmosis in 11 of the 12 cats. Histoplasma infection of multiple organs was found at necropsy. In this study, disseminated histoplasmosis had a higher prevalence in cats than in dogs at the same veterinary medical teaching hospital. Feline disseminated histoplasmosis was not associated with FeLV infection. Treatment was attempted in 7 of the 12 cats.     

Disseminated Canine Histoplasmosis: A Clinical Survey of 24 Cases in Texas

The clinical features of 24 cases of disseminated canine histoplasmosis are presented. The enteric form predominated and the age at presentation was from five months to ten years. The principal clinical findings were chronic diarrhea, weight loss, pyrexia and anemia.

A premortem diagnosis was reached in 20 cases, by demonstrating Histoplasma capsulatum organisms in peripheral blood smears, rectal scrapings or surgical biopsies. Five of seven dogs treated with amphotericin B were released in asymptomatic condition. Four of these cases relapsed six to 15 months following therapy. The overall mortality rate was 80%.

     

Diagnosis of histoplasmosis by detection of the internal transcribed spacer region of fungal rRNA gene from a paraffin-embedded skin sample from a dog in Japan

The lesions of histoplasmosis in dogs in Japan differ from those in dogs in North America. Affected dogs in Japan have had multiple granulomatous or ulcerated foci in skin or gingiva and have not had pulmonary or gastrointestinal lesions. The present report introduces a polymerase chain reaction (PCR) diagnosis of canine histoplasmosis and the characteristic of disease in Japan. The surgically removed skin ulcerate samples from a 5-years-old female Shiba-inu native to Japan without traveling out of the country were evaluated. Tissue samples had many yeast-like organisms in the macrophages. DNA was extracted from paraffin-embedded tissue samples. A nested PCR technique was applied. The detected sequence of the internal transcribed spacer of ribosomal RNA gene had 99.7% in homology with Ajellomyces capsulatus (the teleomorph of Histoplasma capsulatum). Clinical manifestations, historical background of equine epizootic lymphangitis in Japan, and a human autochthonous case of histoplasmosis farciminosi indicated that this dog might have been infected with H. capsulatum var. farciminosum as a heteroecism.     

Diagnosis of histoplasmosis in a dog by cytologic examination of CSF

A mixed inflammatory cell pleocytosis was identified in a cytocentrifuged sample of cerebrospinal fluid (CSF) and diagnosis of histoplasmosis was made on the basis of finding Histoplasma capsulatum organisms within macrophages. This dog had disseminated histoplasmosis with multiple organ involvement including the central nervous system (CNS) and eye.     

Disseminated histoplasmosis in a Bengal tiger (Panthera tigris)

Disseminated infection with Histoplasma capsulatum was diagnosed in a 7-yr-old female Bengal tiger (Panthera tigris). Clinical signs were nonspecific with the exception of brief periods of tachypnea for 5 days prior to death. H. capsulatum organisms were found in the lungs, tracheobronchial lymph nodes, and liver. Diagnosis was confirmed by tracheal wash, urine H. capsulatum enzyme immunoassay, and necropsy results. This report represents the first published account of disseminated histoplasmosis in a tiger.     

Use of corticosteroids for treating dogs with airway obstruction secondary to hilar lymphadenopathy caused by chronic histoplasmosis: 16 cases (1979-1997).

OBJECTIVE: To examine use of corticosteroids in treating dogs with airway obstruction secondary to hilar lymphadenopathy caused by chronic histoplasmosis. DESIGN: Retrospective study. ANIMALS: 16 dogs. PROCEDURE: Records for dogs with airway obstruction examined from January 1979 through December 1997 were reviewed. Dogs were included in the study if they had hilar lymphadenopathy documented radiographically and bronchoscopically, had serum antibodies against Histoplasma capsulatum, and did not have organisms in any cytologic or histologic samples. Dogs were assigned to groups on the basis of treatment given (5 dogs, corticosteroids only; 5 dogs, corticosteroids and antifungal medication; 6 dogs, antifungal medication only). RESULTS: Clinical signs resolved in < 1 week in dogs treated only with corticosteroids. In dogs treated with corticosteroids and an antifungal medication, improvement was evident in a mean of 2.6 weeks. In 5 of 6 dogs treated with only an antifungal medication, clinical signs resolved in a mean of 8.8 weeks. Dogs receiving corticosteroids did not develop active or disseminated histoplasmosis. CLINICAL IMPLICATIONS: Corticosteroids can be used successfully in the treatment of dogs with hilar lymphadenopathy secondary to histoplasmosis. Affected dogs must be carefully evaluated for active infection. Specimens obtained by means of bronchoalveolar lavage, tracheal washing, or other methods should be examined to exclude the possibility of an active infection, which could result in corticosteroid-induced dissemination of disease.     

Clinical laboratory evaluation of deep mycotic diseases in dogs

A retrospective study of 27 dogs with deep mycoses was conducted to evaluate the usefulness of initial laboratory results in determining a diagnosis. Fifteen cases of disseminated blastomycosis, five cases of disseminated histoplasmosis and seven cases of gastrointestinal phycomycosis were studied. Haematologic results consistent with a chronic inflammatory disease (mild to moderate anaemia and moderate to marked monocytosis) were common findings in blastomycosis and phycomycosis. Cases of histoplasmosis were characterized by a more severe anaemia with a neutrophilia and left shift. The severe anaemia present in three out of five (3/5) dogs with histoplasmosis was apparently due to myelophthisis and intravascular erythrocyte fragmentation. Coagulation function tests and/or the haemograms suggested the presence of microangiopathic haemolysis in four dogs with histoplasmosis. Clinical chemistry results in blastomycosis and phycomycosis were usually unremarkable. Hepatic lesions in histoplasmosis were suggested by increases in serum alkaline phosphatase and decreases in serum albumin. Cytology was frequently diagnostic for blastomycosis (11/13 cases) and histoplasmosis (3/4 cases) but was inconsistent in phycomycosis (1/3 cases).     

Clinical and hematologic effects of experimental infection of dogs with recently identified Babesia gibsoni-like isolates from Oklahoma

OBJECTIVE: To characterize clinical and hematologic responses in dogs following experimental inoculation with Babesia gibsoni-like isolates from infected dogs in Oklahoma. DESIGN: Prospective study. ANIMALS: 6 mixed-breed dogs. PROCEDURE: 2 dogs were inoculated with organisms from a naturally infected dog, and 3 were inoculated with organisms from a second naturally infected dog (1 of these 3 dogs was splenectomized 1 week prior to inoculation). One dog was not inoculated. Complete blood counts were performed weekly. RESULTS: In the 5 dogs inoculated with organisms, parasites were initially detected 1 to 5 weeks after inoculation, and severity of parasitemia peaked with 1.9 to 6.0% of RBC infected by 4 to 6 weeks after inoculation. Parasitemia was easily detectable (> 0.1% of RBC infected) for 3 to 4 weeks. Clinical abnormalities included lethargy, fever, and pale mucous membranes but were mild to nearly inapparent in 2 dogs. All dogs developed regenerative anemia and marked thrombocytopenia. Thrombocytopenia developed before and lasted longer than the parasitemia. Profound but transient neutropenia was detected in some dogs. The splenectomized dog developed more severe parasitemia and anemia and more pronounced clinical abnormalities. Three dogs with intact spleens recovered without treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that 2 or more genotypically distinct, but morphologically identical, small Babesia parasites can infect dogs in the United States. Compared with infection with small Babesia parasites from California, infection with these isolates resulted in less severe parasitemia and clinical abnormalities. Parasitemia was transient, indicating that identification of organisms in blood smears may be difficult in some dogs.     

Cytologic analysis of tracheal wash specimens and bronchoalveolar lavage fluid in the diagnosis of mycotic infections in dogs

Tracheal wash and bronchoalveolar lavage fluid analyses were performed in 9 dogs that had mycotic infections with pulmonary involvement. Characteristic organisms were identified in tracheal wash fluid in 3 of 7 dogs with blastomycosis. Organisms were identified in bronchoalveolar lavage fluid in 5 of 7 dogs with blastomycosis and in one dog with histoplasmosis. Organisms were not found in either fluid in one dog with coccidioidomycosis. These procedures should be considered for dogs with suspected mycotic infections that involve the lungs and that cannot be diagnosed by less invasive means.     

Clinical evaluation of urine Histoplasma capsulatum antigen measurement in cats with suspected disseminated histoplasmosis

Diagnosis of Histoplasma capsulatum infection in cats traditionally relies upon identification of organisms in circulating monocytes or in tissue specimens from affected organs. In this retrospective study, results of a urine antigen assay were compared with standard diagnostic methods in cats with clinical signs suggestive of histoplasmosis. Antigenuria was detected in 17/18 cats with a histopathologic or cytopathologic diagnosis of histoplasmosis. This preliminary evaluation of the Histoplasma urine antigen test suggests it may be a useful aid in diagnosing this disease in cats.     

Identification of Histoplasma organisms in circulating eosinophils of a dog

Disseminated histoplasmosis was diagnosed in a 10-year-old dog that had chronic diarrhea, weight loss, fever, and anemia. The diagnosis was based on detection of Histoplasma organisms in circulating neutrophils, monocytes, and eosinophils. The dog had severe histoplasmal fungemia, which may have been caused by treatment with prednisolone.     

Hemostatic Abnormalities in Dogs With Hemangiosarcoma

The hemostasis profiles of 24 dogs with histologically confirmed hemangiosarcoma were prospectively evaluated. Microangiopathic hemolysis was defined as the presence of schistocytes; disseminated intravascular coagulation was defined as 1) thrombocytopenia, 2) fibrin(ogen) degradation products greater than 10 micrograms/mL, 3) prolongation of one or more coagulation times (activated partial thromboplastin time or one-stage prothrombin time) by greater than 25% of the control, 4) fragmented red blood cells (greater than or equal to 1+ based on a semiquantitative grading scale), and 5) fibrinogen less than or equal to 80 mg/dL. Three of the five criteria listed above had to be met for disseminated intravascular coagulation to be diagnosed. Fifty percent of the dogs were considered to have disseminated intravascular coagulation at presentation. Thrombocytopenia was present in 75% of the dogs and was the most common abnormality. The mean platelet count was 137,800/microL. Twenty-five percent of the dogs died as a result of the hemostatic abnormalities. Only 12% of the dogs had microangiopathic hemolysis without other evidence of disseminated intravascular coagulation. Hemostatic abnormalities are present in many dogs with hemangiosarcoma at the initial clinical presentation and represent an important clinical finding.     

Atypical Histoplasma capsulatum infection in a dog

Disseminated histoplasmosis was diagnosed in a 10-year-old dog suspected of having hepatic carcinoma. Clinical abnormalities included diffuse hepatomegaly, gastrointestinal bleeding, thoracic and abdominal effusion, anemia, leukocytosis, and thrombocytopenia. Histoplasmosis characteristically is a disease of the mononuclear phagocyte system, but in this case was diagnosed by finding Histoplasma capsulatum organisms in neutrophils on the blood smear.     

Risk factors and control of intestinal parasite infections in sled dogs in Poland

Training and racing constitute serious challenges for working sled dogs. Attainment of the highest levels of stamina and speed are possible only by completely healthy dogs. Infections with nematodes as whipworm Trichuris sp. or hookworms Uncinaria/Ancylostoma can significantly reduce the fitness of working dogs leading to anemia or even to death. In the middle of the racing season, between December 2009 and April 2010, 108 individual fecal samples were collected from 25 sled dog kennels situated in different regions of Poland. Saturated salt flotation was performed for helminth egg detection. The immunofluorescent assay MeriFluor Cryptosporidium/Giardia and nested PCRs on 18S rRNA (Cryptosporidium spp.) and TPI gene (Giardia spp.) were carried out for detection of intestinal protozoa. Overall prevalence of 6 species of intestinal parasites was 68% in sled dogs (73/108). In 51 samples the eggs of a single species of helminth were detected (47%), two nematode species were detected in 13%, three species of nematodes were found in two dogs. The most prevalent helminths were the hookworms Uncinaria/Ancylostoma-identified in 36% of kennels, and in 34% of sled dogs. Toxocara eggs were detected in 36% of kennels, in 17% of dogs. Trichuris sp. eggs were found in 20% of kennels (5/25), in 13% of dogs. Cysts/oocysts of intestinal protozoa were detected in 31% of sled dogs. The most prevalent was Giardia spp. infection-in 54% of kennels [13/24], in 28% of dogs. Cryptosporidium spp. infections were identified in 37.5% of kennels [9/24], in 13% of dogs. Two sequenced Giardia isolates presented 100% homology with G. intestinalis Assemblage C isolate (AY228641.1), specific for dogs. A range of factors was shown to affect the prevalence of intestinal parasites in sled dogs. The highest prevalence of parasites was found among dogs from large kennels (housing >3 dogs), in dogs less than 2 years old, and in kennels, where prophylactic treatment was carried out 1-4 times a year. The present study has demonstrated a high prevalence of intestinal parasites in working sled dogs in Poland, including the zoonotic human pathogens Toxocara or Cryptosporidium.     

Cardiac hemangiosarcoma in the dog: a review of 38 cases

During the period 1975 to 1984, a histopathologic diagnosis of primary cardiac hemangiosarcoma was made in 38 dogs at Angell Memorial Animal Hospital. The diagnosis was confirmed by exploratory thoracotomy in 16 cases and at necropsy in 22 cases. At the time of exploratory thoracotomy, 7 dogs were euthanatized because of nonresectability of the primary tumor and/or gross metastatic disease. In 9 dogs, the tumor was resected by removing part of the right atrium. Complications included atrial and ventricular arrhythmias, anemia, disseminated intravascular coagulation, and pneumonia. Prolonged and multiple hospitalizations were a common feature of the postoperative period. Adjuvant therapy was not utilized in any case. The mean survival time was 4 months (2 days to 8 months).     

Diagnosis of microthrombocytosis and immune-mediated thrombocytopenia in dogs with thrombocytopenia: 68 cases (1987-1989).

The mean platelet volume (MPV) was evaluated in 68 dogs with thrombocytopenia attributable to various causes. Platelet size was high or low in some dogs. The most clinically useful observation was that low MPV (microthrombocytosis) was a specific indicator of immune-mediated thrombocytopenia (IMT) in these thrombocytopenic dogs. All but one case of microthrombocytosis (MPV less than 5.4 fl) was found in dogs with IMT. Microthrombocytosis was detected in 17 of 31 dogs with IMT and appeared at the onset of the disease. Macrothrombocytosis (MPV greater than 9.4 fl) indicated active thrombopoiesis, but was not unique to any disease category. Macrothrombocytosis was detected in 18 of 31 dogs with IMT, 3 of 17 dogs with disseminated intravascular coagulation, and 3 of 9 dogs with primary bone-marrow disease.     

Evaluation of granulocytic ehrlichiosis in dogs of Missouri, including serologic status to Ehrlichia canis, Ehrlichia equi and Borrelia burgdorferi.

Canine granulocytic ehrlichiosis was diagnosed in 37 dogs by finding ehrlichial morulae in 0.1 to 26.2% of their blood neutrophils and eosinophils. All 37 dogs had clinical signs of arthritis or muscular stiffness. Titer to Ehrlichia canis was determined in sera from 31 of the 37 dogs; 25 dogs had titer ranging from 1:20 to 1:5,120. In the other 6 dogs, titer to E canis was less than 1:10. The most common hematologic abnormality in these dogs, other than rickettsiemia, was thrombocytopenia. Granulocytes infected with ehrlichial organisms were not found in another 10 dogs that had clinical signs of arthritis or muscular stiffness. Of these 10 dogs, 3 had titer to E canis ranging from 1:40 to 1:320. Titer in the other 7 dogs was less than 1:10. Ehrlichial morulae were not found in the granulocytes of 18 healthy dogs. Of these 18 dogs, 9 had titer to E canis ranging from 1:20 to 1:5,120. Titer in the other 9 dogs was less than 1:10 Titer to Borrelia burgdorferi was determined in dogs with granulocytic ehrlichiosis, arthritic dogs without detected rickettsiemia, and in healthy dogs. Low titer determined by 2 laboratories was considered to be nonspecific reaction in all 3 groups of dogs and, thus, did not indicate that the arthritic disorders were attributable to canine borreliosis.     

Attaching and effacing Escherichia coli infections in calves, pigs, lambs, and dogs

Attaching and effacing Escherichia coli (AEEC) adhere to mucosal epithelium in both small and large intestine and induce a distinctive lesion characterized by an irregular scalloped appearance of the epithelial layer. Infection with attaching and effacing E. coli was detected in 14 calves, 7 pigs, 2 lambs, and 3 dogs. Affected animals were from farms and kennels in South Dakota, Minnesota, Iowa, Nebraska, and Wisconsin. Ages of affected animals were calves, 2 days to 4 months; pigs, 1-6 weeks; lambs, 1 week; and dogs, 7-8 weeks. Clinical signs included diarrhea in all animals, but other nonenteric disease problems were present in some animals. Concurrent infection with other enteropathogens was detected in 9 calves and 5 pigs. Infection with AEEC appeared to be the sole cause of illness and death in some animals. There was evidence of intestinal hemorrhage in 5 of the calves and in all 3 dogs. Attaching and effacing lesions varied from small scattered foci to widespread involvement of large areas of intestinal mucosa. Verotoxin was produced by E. coli strains isolated from 9 calves, but not by strains from pigs, lambs, or dogs.     

Canine hepatic neuroendocrine carcinoma: an immunohistochemical and electron microscopic study

Ten dogs with neuroendocrine carcinoma of the liver were selected for inclusion in the study. Clinical signs were anorexia (7), vomiting (5), polydipsia/polyuria (3), icterus (2), lethargy (2), weight loss (2), paresis (1), ataxia (1), weakness (1), collapse (1), and urinary tract infection (1). Hematologic and biochemical abnormalities included anemia (2/8), leukocytosis (4/8), high liver enzyme activity (serum alkaline phosphatase, 7/9; alanine transaminase, 7/9; aspartate transaminase, 8/9), and high total bilirubin (6/9). Grossly, the tumors were diffuse, involving all liver lobes in six dogs, and two dogs had various-sized nodules in addition to diffuse involvement. Histologically, there were eight tumors with solid or trabecular pattern (group A), one tumor with cords or rows of neoplastic cells (group B), and one tumor with multiple rosette-like structures (group C). Immunohistochemical studies revealed that all 10 neoplasms were positive for at least one of the endocrine markers used: neuron-specific enolase (NSE; 8/10), synaptophysin (5/10), and chromogranin-A (3/10). A panel of NSE, chromagranin-A, and synaptophysin detected 100% of the tumors in our series. Electron microscopy confirmed the diagnosis by the presence of intracytoplasmic neurosecretory granules in the two examined cases. Our results show that neuroendocrine markers commonly used in humans can be used for the diagnosis of hepatic neuroendocrine carcinoma in dogs, preferably a panel of synaptophysin, chromagranin-A, and NSE because chromogranin-A alone is not as useful in dogs as in humans.     

Hepatotoxicity of phenobarbital in dogs: 18 cases (1985-1989).

The medical records of 18 dogs that had hepatic disease and received phenobarbital as an anticonvulsant for 5 to 82 months were reviewed. Clinical signs included sedation and ataxia in all dogs, 5 dogs were also anorectic, 2 had coagulopathy, 3 were icteric, and 5 had ascites. Serum biochemical analysis revealed serum albumin concentration less than or equal to 2.2. g/dl in 12 dogs, serum alkaline phosphatase activity greater than or equal to 169 U/L in 18 dogs, serum alanine transaminase activity greater than or equal to 57 U/L in 15 dogs, and total bilirubin concentration greater than or equal to 1 mg/dl (in the absence of lipemia) in 7 dogs. Serum phenobarbital concentration was greater than or equal to 40 micrograms/ml in 12 of 17 dogs. Sulfobromophthalein excretion was prolonged in 8 of 10 dogs. Preprandial serum bile acid concentrations were high in 8 of 10 dogs, and 2-hour postprandial serum bile acid concentrations were high in 9 of 10 dogs. Two of 4 dogs tested had resting plasma ammonia concentrations greater than 200 mg/dl. An ammonia tolerance test was performed on 2 other dogs; both had ammonia concentration greater than or equal to 200 mg/dl in the plasma 30 minutes after receiving 100 mg of ammonium chloride/kg of body weight, PO. Nine dogs died, 1 was euthanatized, and necropsies were performed on these 10 dogs. Biopsies and necropsies of 6 dogs revealed chronic hepatic fibrosis with nodular regeneration (cirrhosis). One dog had hepatocellular carcinoma and mild cirrhosis. In 1 dog, after phenobarbital had been withheld, necropsy revealed complete recovery of the previously observed lesions.