Epidemiology, diagnosis, and treatment of blastomycosis in dogs and cats

Blastomycosis is one of the most common systemic fungal diseases in dogs in North America, but it is rarely diagnosed in cats. The typical route of infection is inhalation of aerosolized conidia of Blastomyces dermatitidis. From the respiratory tract, the developing yeast form may disseminate throughout the body and affect multiple organ systems, most commonly the lymphatic, skeletal and central nervous systems, eyes and skin. Disseminated disease often is associated with nonspecific signs of illness including lethargy, inappetence and fever, as well as signs referable to specific organ systems like chronic cough and dyspnea, peripheral lymphadenopathy, endophthalmitis, and central nervous signs. Diagnosis is typically made by detection of Blastomyces dermatitidis yeast in affected tissues by fine-needle aspiration cytology or histopathology. The treatment of choice is itraconazole. Prognosis is fair in dogs without central nervous disease and guarded in cats.     

Evaluation of the prevalence of infections in cats after renal transplantation: 169 cases (1987-2003)

OBJECTIVE: To determine the prevalence of infections developing postoperatively, document the contribution of infection to increased risk of death, and identify risk factors associated with the development of infectious complications in cats after renal transplantation. DESIGN: Retrospective study. ANIMALS: 169 cats that received renal allograft transplants. PROCEDURES: Medical records of cats receiving renal transplants at the University of California from January 1987 through December 2003 were reviewed. RESULTS: 47 infections developed in 43 of 169 cats. Bacterial infections were most common (25/47 cats), followed by viral (13/47), fungal (6/47), and protozoal (3/47) infections. The median duration from transplant surgery to development of infection was 2.5 months. Infection was the second most common cause of death after acute rejection of the transplant, accounting for 14% of deaths overall. Cats with concurrent diabetes mellitus had a significantly increased risk of developing an infection after renal transplantation. Sex, increasing age, concurrent neoplasia, and previous treatment for transplant rejection were not associated with development of infection. CONCLUSIONS AND CLINICAL RELEVANCE: Infection was a common complication and an important cause of death or euthanasia in cats after renal transplantation. Development of diabetes mellitus after transplantation significantly increased the risk of infection.     

Biological and DNA evidence of two dissimilar populations of the Rhipicephalus sanguineus tick group (Acari: Ixodidae) in South America

In this work, the biology, mitochondrial DNA and fertility of hybrids from two strains of Rhipicephalus sanguineus, from Brazil and Argentina, were compared. Engorged larvae, nymphs and adults from Argentina weighed more and the engorgement period of adult females was significantly longer than those of their Brazilian counterparts, whereas adult female tick yield rate was higher for the Brazilian strain. High intraspecific divergence of mitochondrial DNA was detected between R. sanguineus from Brazil and Argentina. On the other hand, a strong genetic relationship was detected between European and Argentinean R. sanguineus populations while the Brazilian population appeared to be related to the African Rhipicephalus turanicus. Adult hybrid females laid eggs, which were mostly unviable, whereas a mean of more than 1400 larvae hatched per egg mass from pure Brazilian and Argentinean strains. These results showed that differences between these strains are greater than previously assumed and that the biosystematic status of R. sanguineus ticks from South America should be re-evaluated. Wide variations, such as these might account for the reported worldwide differences in biology and vector capacity of this species.     

Oesophageal strictures in cats associated with doxycycline therapy

Four cases of oesophageal stricture subsequent to doxycycline administration are reported. All cases were young to middle age (median age 3 years; range 1-7 years), and either domestic shorthair or domestic longhair breed. In all cases the predominant clinical sign was regurgitation, which developed at variable times after doxycycline administration. In all cases the reason for doxycycline use was treatment or prophylaxis of suspected infections (Mycoplasma haemofelis, Chlamydophila felis or Bordetella bronchiseptica), and the duration of therapy was variable. In one case the stricture was definitively diagnosed at post mortem examination, in the three other cases, definitive diagnosis was by endoscopy. Balloon dilation was successful in the three cases that were treated. This is the largest case series, to date, of oesophageal disease in cats associated with doxycycline administration. Caution should be exercised when administering oral medication to cats, especially doxycycline, and should be accompanied either by a water or food swallow.     

Histoplasmosis in dogs and cats

Histoplasma capsulatum is endemic throughout most of the United States with a high prevalence of infections in the Midwest and South. Histoplasmosis is the second most common systemic fungal disease in cats that may be more susceptible than dogs. Infection occurs by inhalation of conidia from the mycelial phase, which subsequently convert to the yeast form. Histoplasma capsulatum is phagocytized and harbored by cells of the mononuclear phagocyte system. Infection may be subclinical or cause clinical pulmonary granulomatous disease or dissemination. Disseminated disease predominantly affects the liver, spleen, gastrointestinal tract, bone and bone marrow, integument, and eyes. Primary gastrointestinal histoplasmosis also occurs. Clinical signs of histoplasmosis often are nonspecific, including chronic wasting, fever, anorexia, respiratory signs, and lameness. Gastrointestinal signs (eg, diarrhea with hematochezia or melena) are common in dogs. The definitive diagnosis is made by identification of the yeast in tissue samples. Itraconazole is the treatment of choice.     

TENESMUS AND STRANGURIA FROM A CYSTIC UTERINE REMNANT

A 14-year-old domestic short hair spayed female cat was examined for tenesmus and stranguria. The abdominal mass discovered was removed and found to be a cystic uterine remnant. Tenesmus and stranguria resolved following mass removal.     

Long-term study of incidence and financial loss due to cattle babesiosis in an Argentinian dairy farm

The incidence and direct financial loss caused by babesiosis were evaluated in 121 Holstein Friesian female cattle that formed eight cohorts (1981–1988) of a dairy farm located approximately 24° 55′S 65° 29′W in Salta, Argentina. Female calves born in 1986 and 1987 (n=32) were vaccinated with a live Babesia vaccine at six months of age.

No cases of babesiosis occurred in the vaccinated cattle. The incidence of babesiosis in the six non-vaccinated cohorts was 23.6% (21/89). Eighteen of the cases were the result of Babesia bovis, one to Babesia bigemina and two to a mixed infection. Two cattle died of B. bovis infection in spite of drug treatment (diaminazene, 3.5 mg kg⁻¹). No disease occurred in cattle younger than seven months or older than 24 months. The number of cases according to age of cattle was: 7–9 months, 5; 10–12 months, 6; 13–24 months, 10.

Financial loss for the six cohorts that suffered clinical cases amounted to US $ 1624.6 (prices in October 1990)—62% were the result of physical losses and 38% to costs of control. A benefit-cost analysis of vaccination was carried out assuming that 95% of the mortality and morbidity losses of the six non-vaccinated cohorts was prevented after a single inculation of a live vaccine (cost of a dose plus administration was US $ 4.2. The benefit-cost ratio was 4:1 for each US dollar expended.