Medical management of pituitary-dependent hyperadrenocorticism: mitotane versus trilostane.

Pituitary-dependent hyperadrenocorticism is a common endocrine disorder in dogs in the United States. Once a diagnosis is established, a decision must be made whether or not to pursue treatment, and if so, which medication to use. Historically, mitotane (Lysodren, o,p'-DDD, Bristol-Myers Squibb, New York) has been the most commonly used treatment for medical management. Its use is complicated and comes with many potential side effects, making many practitioners wary of its use. Recently, trilostane has been proven to be an effective treatment of pituitary-dependent hyperadrenocorticism and is approved for use in other countries. Treatment with trilostane is somewhat simpler and the incidence of side effects seems to be less when compared with mitotane therapy. Either treatment can be a safe and effective method of treatment for pituitary-dependent hyperadrenocorticism when the practitioner and client are well educated regarding their use and an appropriate monitoring protocol is used.

The prevalence of microalbuminuria and proteinuria in cats with diabetes mellitus.

The prevalence of microalbuminuria (MA) and proteinuria was evaluated in 66 cats with diabetes mellitus (DM), 35 nondiabetic cats with other illness, and 11 healthy nondiabetic cats with use of the E.R.D.-HealthScreen Feline Urine Test. The MA prevalence was higher in the diabetic than in the nondiabetic sick and healthy control cats (70%, 39%, and 18% respectively, P < .0001). In addition, prevalence of proteinuria defined by a protein/creatinine ratio (UPC) > 0.4 was significantly higher in the diabetic cat than in the control cats (70%, 35%, and 9% respectively, P < .0001). There was a significant but weak correlation between the results of MA and UPC (P < .0001, r = 0.43). Our results showed that MA is common in cats with DM. Further studies are required to evaluate the prognostic value of the presence and the severity of MA in cats with DM.

Feline nonregenerative anemia: pathophysiology and etiologies.

Nonregenerative anemia in cats results from the inability of the bone marrow to respond appropriately to a peripheral deficiency in RBCs. There are many causes of nonregenerative anemia, including primary diseases of the bone marrow and systemic diseases that have secondary effects on the bone marrow. The prognosis is variable: some etiologies are reversible, whereas others may be chronic or fatal.

Feline nonregenerative anemia: diagnosis and treatment.

Anemia in cats is not a diagnosis but rather a sign of an underlying disease. The diagnostic work-up for an anemic patient is often extensive, starting with classification of the anemia as regenerative or nonregenerative. Once nonregenerative anemia is diagnosed, a number of tests may be required to determine its cause, including a close examination of the patient's blood and bone marrow. Although there are standard supportive measures for anemic cats, specific therapies can be implemented for certain etiologies of nonregenerative anemia.

Medical management of pituitary-dependent hyperadrenocorticism: mitotane versus trilostane.

Pituitary-dependent hyperadrenocorticism is a common endocrine disorder in dogs in the United States. Once a diagnosis is established, a decision must be made whether or not to pursue treatment, and if so, which medication to use. Historically, mitotane (Lysodren, o,p'-DDD, Bristol-Myers Squibb, New York) has been the most commonly used treatment for medical management. Its use is complicated and comes with many potential side effects, making many practitioners wary of its use. Recently, trilostane has been proven to be an effective treatment of pituitary-dependent hyperadrenocorticism and is approved for use in other countries. Treatment with trilostane is somewhat simpler and the incidence of side effects seems to be less when compared with mitotane therapy. Either treatment can be a safe and effective method of treatment for pituitary-dependent hyperadrenocorticism when the practitioner and client are well educated regarding their use and an appropriate monitoring protocol is used.

Hyperthyroidism and the kidney.

Hyperthyroidism and chronic renal failure (CRF) are both common diseases of older cats. Hyperthyroidism increases GFR by a variety of physiologic effects. Chronic renal failure can suppress total T4 concentrations in cats with concurrent hyperthyroidism, and free T4 is not a useful distinguishing test. Medical therapy (ie, methimazole) is recommended in cats with pre-existing CRF. Overt renal failure occurs in approximately 30% of cats treated for hyperthyroidism. It usually occurs within one month of treatment and tends to remain mild and stable over time. There is no practical way to predict which cats will develop CRF after treatment of hyperthyroidism, although GFR measurement does seem useful.

Urinalysis interpretation: how to squeeze out the maximum information from a small sample.

The urinalysis is an essential part of the diagnostic evaluation for all urinary and many metabolic diseases. Its assessment includes evaluation of physical characteristics (color, clarity, and volume), biochemical parameters (urine pH, blood, glucose, ketones, bilirubin, urobilinogen, and protein) and microscopic sediment evaluation (RBC, WBC, organisms, epithelial cells, crystals, and casts). Many of these parameters are influenced by collection method and therefore, it is essential to interpret accordingly. Knowledge of factors that can interfere with the accuracy of some test results can decrease improper interpretation. When all of these parameters are evaluated in combination with clinical signs, physical examination, thorough history and other laboratory tests, a diagnosis will often be attained.

Red blood cell transfusions in cats: 126 cases (1999).

OBJECTIVE: To determine the number of and reasons for RBC transfusions, incidence of acute transfusion reactions, prevalence of blood types, volume of blood administered, change in PCV, and clinical outcome in cats. DESIGN: Retrospective study. ANIMALS: 126 cats that received RBC transfusions. PROCEDURE: Medical records of cats that received whole blood or packed RBC transfusions were reviewed for signalment, blood type, pre- and post-transfusion PCV, volume of blood product administered, clinical diagnosis and cause of anemia, clinical signs of acute transfusion reactions, and clinical outcome. RESULTS: Mean volume of whole blood administered i.v. was 172 mL/kg (7.8 mL/lb) versus 9.3 mL/kg (4.2 mL/lb) for packed RBCs. Ninety-four percent of cats had blood type A. Mean increase in PCV among all cats was 6%. Fifty-two percent of cats had anemia attributed to blood loss, 10% had anemia attributed to hemolysis, and 38% had anemia attributed to erythropoietic failure. Acute transfusion reactions occurred in 11 cats. Sixty percent of cats survived until discharge. CONCLUSIONS AND CLINICAL RELEVANCE: RBC transfusions resulted in an increase in PCV in cats with all causes of anemia in this study. The rate of death was greater than in cats that did not receive transfusions, but seriousness of the underlying disease in the 2 groups may not be comparable. Death rate of cats that received transfusions was not attributable to a high rate of transfusion reactions. Results confirm that pretransfusion blood typing or crossmatching is required to minimize the risk of adverse reactions.

Canine and feline blood donor screening for infectious disease.

Thousands of blood transfusions are performed each year on dogs and cats, and the demand for blood products continues to grow. Risks associated with transfusions include the risk of disease transmission. Appropriate screening of blood donors for bloodborne infectious disease agents should be performed to lessen this risk. Geographic restrictions of disease, breed predilection, and documentation of actual disease transmission by transfusion all are factors that might need to be considered when making a decision on what screening program to use. In addition, factors involving general health care and management of blood donors should be employed to further ensure blood safety.

Infection and blood transfusion: a guide to donor screening.

In recent years, blood-component therapy has become more accessible in veterinary practice. As with human medicine, care must be taken to minimize the risk of disease transmission from donor to recipient. Determining the appropriate diseases to screen for is complicated by regional variations in disease incidence, the existence of chronic carrier states for some diseases, the difficulty in screening-test selection, and testing cost. The feline diseases considered include retroviral infections, feline coronaviruses, ehrlichiosis (Ehrlichia canis-like), anaplasmosis (Anaplasma phagocytophilum), neorickettsiosis (Neorickettsia risticii), hemoplasmosis (Mycoplasma hemofelis and M. hemominutum, previously feline hemobartonellosis), and cytauxzoonosis (Cytauxzoon felis). The canine diseases considered in this paper include babesiosis (Babesia canis and B. gibsonii,) ehrlichiosis (E. canis and E. ewingii), anaplasmosis (A. phagocytophilum), neorickettsiosis (N. risticii var. atypicalis), leishmaniasis (Leishmania donovani complex), brucellosis (Brucella canis), hemoplasmosis (M. hemocanis, previously canine hemobartonellosis), and bartonellosis (Bartonella vinsonii).

The use of erythropoietin.

EPO is a hematopoietic growth factor produced in the kidney that stimulates erythropoiesis. It effectively treats hypoproliferative anemia associated with CRF, improving quality of life in these patients. Other uses that are poorly characterized in veterinary medicine include treatment of cancer patients on chemotherapy, hematologic disorders, and anemic FeLV-infected cats as well as preoperative conditioning for elective surgeries that may involve significant blood loss. Careful monitoring of therapy is necessary for optimal results. Several complications are associated with rHuEPO therapy. The production of anti-rHuEPO antibodies is the most significant and can be a life-threatening event. Alternatives to human EPO are being sought to provide beneficial effects while avoiding antibody formation.