The use of the rapid osmotic fragility test as an additional test to diagnose canine immune-mediated haemolytic anaemia

Background

Diagnosing canine immune-mediated haemolytic anaemia (IMHA) is often challenging because all currently available tests have their limitations. Dogs with IMHA often have an increased erythrocyte osmotic fragility (OF), a characteristic that is sometimes used in the diagnosis of IMHA. Since the classic osmotic fragility test (COFT) is time-consuming and requires specialized equipment, an easy and less labour-intensive rapid osmotic fragility test (ROFT) has been used in some countries, but its diagnostic value has not yet been investigated.This study aimed to evaluate erythrocyte osmotic fragility in dogs with and without IMHA, to compare results of the classic (COFT) and rapid (ROFT) test and to assess the value of the ROFT as diagnostic test for canine IMHA.Nineteen dogs with IMHA (group 1a), 21 anaemic dogs without IMHA (group 1b), 8 dogs with microcytosis (group 2), 13 hyperlipemic dogs (group 3), 10 dogs with lymphoma (group 4), 8 dogs with an infection (group 5) and 13 healthy dogs (group 6) were included.In all dogs, blood smear examination, in-saline auto-agglutination test, Coombs’ test, COFT and ROFT were performed. In the COFT, OF5, OF50 and OF90 were defined as the NaCl concentrations at which respectively 5, 50 and 90% of erythrocytes were haemolysed.

Results

Compared with healthy dogs, OF5 and OF50 were significantly higher in group 1a (P < 0.001) and OF5 was significantly higher in group 3 (P = 0.0266). The ROFT was positive in 17 dogs with IMHA, 10 hyperlipemic dogs, one anaemic dog without IMHA and one healthy dog.

Conclusions

Osmotic fragility was increased in the majority of dogs with IMHA and in dogs with hyperlipidemia, but not in dogs with microcytosis, lymphoma or an infection. Although more detailed information was obtained about the osmotic fragility by using the COFT, the COFT and ROFT gave similar results. The ROFT does not require specialized equipment, is rapid and easy to perform and can be used easily in daily practice. Although, the ROFT cannot replace other diagnostic tests, it may be a valuable additional tool to diagnose canine IMHA.     

Improved clinical approach to the diagnosis of canine ehrlichiosis

Summary Canine ehrlichiosis is being recognised with increasing frequency in many parts of the world. Based upon a detailed clinical and laboratory examination including a simplein vitro blood culture diagnostic test 373 cases have been classified into seven broad groups. These groups include acute, haemorrhagic, chronic, uraemic, subclinical, carrier state and those with babesiosis. While many of these groups overlap they will assist the clinician in diagnosis and allow the application of specific thereapy before the disease progresses to a chronic irreversible stage.

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Metodologia Clinica Mejorada Para El Diagnostico De La Ehrlichiosis Canina

Resumen La Ehrlichiosis canina es una enfermedad ampliamente conocida a nivel mundial. Con base en exámenes clínicos y de laboratorio detallados, incluyendo una prueba diagnóstica simple de cultivo de sangrein vitro, 373 casos han sido clasificados en siete grupos generales. Estos grupos incluyen la forma aguda, hemorrágica, crónica, urémica, subclínica y de portador crónico y aquellos casos con babesiosis. A pesar de que muchos de estos grupos se confunden, la clasificación adoptada asiste al clínico en el diagnóstico, permitiendo la aplicación de una terápia específica antes que la enfermedad progrese hacia un estado crónico irreversible.

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Amelioration De La Demarche Clinique Pour Le Diagnostic De L'Ehrlichiose Canine

Résumé L'ehrlichiose canine est reconnue avec une fréquence de plus grande dans beaucoup de parties du monde. Basée sur un examen clinique détaillé et des tests de laboratoire, dont une mise en culturein vitro du sang, 373 cas ont été classés en 7 grands groupes. Ces groupes sont: aigu, hémorragique, chronique, urémique, subclinique, porteur et ceux associés à la babésiose. Bien qu'il y ait un recoupement entre ces groupes, ils apporteront une aide au clinicien pour son diagnostic et permettront la mise en oeuvre d'une thérapeutique spécifique avant que la maladie ne progresse à un stade chronique irréversible.

     

The use of skin delayed-type hypersensitivity as an adjunct test to diagnose brucellosis in cattle: a review

Brucellosis, caused by bacteria of the genus Brucella, is a contagious disease that causes economic loss to owners of domestic animals due to loss of progeny and milk yield. Because cattle, sheep, goats, and to a lesser extent pigs are considered to be the source of human brucellosis, serological tests have been used to screen domestic animals for antibodies against Brucella. Although the serological tests helped to eradicate brucellosis in many countries, serological tests are not always adequate to detect latent carriers of Brucella. Therefore, the use of the skin delayed-type hypersensitivity (SDTH) test, which is independent of circulating antibodies, might improve the diagnosis of brucellosis. In the literature, however, there are conflicting reports as to the value of the SDTH test for the diagnosis of brucellosis. Some studies consider the test unreliable, whereas others advocate its use because it detects brucellosis earlier than serological tests. The objectives of this study were therefore to assess the characteristics of the SDTH test, to select a Brucella strain that will yield a suitable brucellin for use in the field, and to determine whether the use of serological tests in combination with the SDTH test improves the detection of brucellosis. The results of this study clearly show that the SDTH test detects latent carriers of Brucella and confirms brucellosis in cattle with ambiguous serological test results. Brucellins prepared from smooth or mucoid strains of Brucella are better suited for use in the field than brucellins prepared from rough strains because they detect brucellosis in cattle with acute as well as chronic infection. The SDTH test is highly specific (99.3% specificity), and repeated testing of naive cattle or cattle infected with microorganisms that serologically cross-react with Brucella does not sensitize cattle to subsequent SDTH tests. However, it is possible that some naive cattle may serologically react to the injection of brucellin. The effect of these serological reactions on the sero-diagnosis of brucellosis is limited, because cattle may only now and then react serologically either with the serum agglutination test (SAT) or the complement fixation test (CFT). Nevertheless, cattle infected with microorganisms that serologically cross-react with Brucella may test seropositive for brucellosis 4 to 7 weeks after injection of brucellin, depending on the cross-reacting microorganism. The value of the SDTH test for the diagnosis of brucellosis was demonstrated after an outbreak of brucellosis. When the SDTH test was used in combination with SAT and CFT at diagnostic threshold > or =2 mm or > or =1 mm (increase in skinfold thickness), respectively, 39/44 (88%) or 42/44 (95%) of the infected cattle were detected compared with only 27/44 (61%) when SAT and CFT were used. When cattle in areas of low prevalence or in areas free from brucellosis are tested with the SDTH test an increase > or =2 mm in skinfold thickness should be considered indicative of infection. When the control and eradication of brucellosis is based on test-and-slaughter, an increase of > or =1 mm in skinfold thickness should be considered indicative of infection. Repeated serological testing complemented with the SDTH test in this programme will shorten the quarantine (movement control) period of a suspect herd, limiting the financial loss incurred during outbreaks of the disease. Consequently, since the SDTH test usually does not interfere with the serological diagnosis and can safely be used to establish the infection status of cattle in a suspect herd, it is opportune to consider adding the SDTH test to the procedure currently used to diagnose brucellosis in individual animals.     

The use of 17-hydroxyprogesterone in the diagnosis of canine hyperadrenocorticism

A number of dogs are seen with clinical signs consistent with hyperadrenocorticism (HAC), supporting CBC and biochemical findings, but the disease cannot be confirmed with either the ACTH stimulation test or the low-dose dexamethasone suppression test (LDDST). Therefore, another screening test is required to aid diagnosis in these atypical cases of HAC. The aim of this study was to investigate whether measuring 17-hydroxyprogesterone (OHP) concentrations could be used in this role. Plasma cortisol and OHP concentrations were measured in dogs with clinical signs suggestive of HAC before and after administration of exogenous ACTH. In dogs with HAC, plasma OHP showed an exaggerated response to ACTH stimulation. This was seen in both typical cases of HAC with a positive cortisol response to ACTH administration and in atypical cases with negative screening test results. The test can be performed on plasma already taken for a conventional ACTH stimulation test. Post-ACTH OHP concentrations decreased after treatment with mitotane or adrenalectomy. These results suggest that OHP measurements can be used as an aid to diagnose and manage canine HAC.     

The use of a brucella protein antigen in dermal hypersensitivity as an adjunct method to diagnose bovine brucellosis

A total of 191 cows in 3 herds were injected with a brucella protein antigen in an effort to compare serologic and bacteriologic findings with delayed hypersensitivity and to possibly detect incubative brucellosis. Using cultural and serologic results, the responses to the BPA antigen were inferior to serologic tests in the diagnosis of infection. None of the 23 skin test positive/seronegative cows were positive on subsequent herd blood tests.     

The pathogenesis and diagnosis of canine hip dysplasia: a review.

Hip dysplasia is a common developmental problem affecting the canine population. Despite extensive research into the condition, many questions remain unanswered and numerous misconceptions are present among the general public. The purpose of this paper is to review the current knowledge on the development of hip dysplasia, factors modifying its development, and current diagnostic techniques. A computerized literature search was conducted for the period of January 1983 to April 1985 using the MEDLINE and CAB databases, and the keywords hip dysplasia, hip, dog, and canine. Other articles, wherever possible original research articles, published before 1983 were also reviewed. Animals affected by hip dysplasia are born with normal hips, but quickly develop subluxation of the femoral head. Degenerative joint disease follows. Hip dysplasia is a complex, inherited, polygenic trait. Selective breeding of only normal dogs with normal littermates, parents, and grandparents is the recommended method of reducing the incidence in the general population. Gene expression in affected individuals may be modified by a number of environmental factors. These factors do not cause hip dysplasia, but they alter manifestations of the trait and its severity. Nutrition is a major environmental factor. Excess energy consumption increases the frequency and severity of hip dysplasia in genetically predisposed dogs. Food intake should be regulated to maintain a slender figure with the ribs and dorsal vertebral spines easily palpable, but not visible. Excess dietary calcium and vitamin D contribute to hip dysplasia in genetically predisposed individuals and should be avoided. High dose vitamin C supplementation in growing puppies does not prevent hip dysplasia, and this practice should be discontinued.(ABSTRACT TRUNCATED AT 250 WORDS)     

The use of copper levels in hair to diagnose hypocuprosis

The possibility of using hair to help diagnose hypocuprosis was investigated. Diets containing different levels of molybdenum and sulphur were fed to nine Hereford steers. Liver reserves of copper were depleted rapidly when dietary levels of molybdenum and sulphur exceeded 2.7 mg/kg and 3.8 g/kg respectively. Following the onset of diarrhoea, liver reserves of copper were repleted by injecting copper glycinate. Samples of liver, blood and hair were collected at regular intervals and analysed for copper. Progressive changes in liver levels of copper were closely paralleled by changes in copper levels in hair and plasma. Relationships between copper levels in liver and plasma, and the liver and hair were both shown to be asymptotic. Plasma and hair levels were sensitive to changes in liver reserves below about 20 microgram/g, but changed little above this level. Sampling variation was shown to be less with hair than with plasma. It was concluded that copper levels in hair are a useful diagnostic aid in detecting hypocuprosis. Hair provides an integrated record of copper availability during its period of growth, and thus may be preferred to blood plasma which represents only a spot sample in time.     

The immunological approach to pregnancy diagnosis: a review

The developing embryo/fetus bears antigens which are foreign to the mother and it could be expected that immune rejection of the conceptus would occur. One of the reasons why the fetus is not rejected is because a depression of the maternal immune response takes place during pregnancy. Serum from pregnant animals of several species has been shown to contain a factor, early pregnancy factor (EPF), which is immunosuppressive. EPF has been detected as early as six hours after mating and its detection could aid diagnosis of early pregnancy in all species.     

Interobserver agreement in the diagnosis of canine hip dysplasia using the standard ventrodorsal hip-extended radiographic method

OBJECTIVES: To determine the agreement between observers and to investigate the effect of observer experience in diagnosing canine hip dysplasia and providing final scoring of hips using the standard ventrodorsal hip-extended radiographic method. The agreement of the final scoring, with a presumed correct assessment based on the Norberg angle, is also investigated. METHODS: Thirty observers were requested to read 50 ventrodorsal hip-extended radiographs of 25 dogs according to Federation Cynologique International criteria. Groups of experienced (nine members) and inexperienced (21 members) observers were used. RESULTS: For providing the distinction between dysplastic versus non-dysplastic dogs, the average interobserver agreement was 72 per cent and was significantly higher (P<0.0001) than the score that could be expected by chance without any agreement between observers. For providing the final score (A, B, C, D or E), an average interobserver agreement of 43.6 per cent was found. In the experienced group, an agreement score of 76 per cent was found for the distinction between AB versus non-AB and an agreement score of 81 per cent was found for the distinction between C versus non-C. The agreement score was significantly higher (P<0.0001) for the experienced group than for the inexperienced group in all cases. Agreement between the presumed correct assessment based on the Norberg angle and the observer's evaluation was low (P=0.35), irrespective of whether the observers were experienced (71.8 per cent correct assessments) or inexperienced (69 per cent correct assessments). CLINICAL SIGNIFICANCE: Although interobserver agreement is low, observer experience increases agreement.     

Canine pruritus: an approach to diagnosis. Stage I. Preliminary investigation*

This series of three papers describes a straightforward, systematic approach to the investigation of canine pruritus. Those dermatoses which regularly present with this symptom are discussed, with emphasis being placed on clinical signs, diagnosis and differential diagnosis. In this first paper, the author discusses the preliminary investigation of the itching dog.     

Microfocal radiography as an aid to the diagnosis of canine elbow osteochondrosis

One normal cadaver specimen and six labrador retrievers with suspected elbow osteochondrosis were examined using a microfocal radiographic technique as an aid to diagnosis. This allowed the production of a magnified image (macro-radiograph) with high spatial resolution. The macroradiographs were compared with radiographs obtained using a standard technique to see if they facilitated decision making with respect to case management. The lesions that were suspected from radiographic examination were correlated with the gross lesions found at elbow arthrotomy. Microfocal radiography gave additional information about the changes within the joints but it still remained difficult to image the lesion satisfactorily in some cases.     

Dermatology of reptiles: a clinical approach to diagnosis and treatment.

As herpetoculture becomes more commonly practiced, many of the dermatologic problems discussed in this article will be encountered less frequently. Many of the problems result from a general lack of knowledge regarding proper nutrition, husbandry, and the overall needs of reptiles within a captive environment. As reptiles become more a part of the mainstream pet population, information about their care will undoubtedly become more accessible, and as more captive-raised reptiles become available in the pet trade, many of the dermatoses currently associated with wild-caught animals will become less common.     

Canine pruritus: an approach to diagnosis. Stage II. Infestations and infections*

This series of three papers describes a straight forward, systematic approach to the investigation of canine pruritus. Those dermatoses which regularly present with this symptom are discussed, with emphasis being placed on clinical signs, diagnosis and differential diagnosis. This second paper details the parasitic infestations and bacterial and clinically similar conditions which may result in pruritus.     

The acute abdomen: a surgeon's approach to diagnosis and treatment

Clinical approach to a patient with acute abdominal distress involves decision making: whether to take a patient to surgery, or manage the patient medically. A thorough and systematic approach requires the use of diagnostic imaging modalities, including radiology and ultrasonography, performing diagnostic peritoneal lavage or abdominal paracentesis techniques, and bloodwork evaluation, including complete blood count and serum biochemistry profiles. In some cases, the results of diagnostic tests may lead to surgical versus medical management, particularly when a patient fails to respond to medical management alone. In other cases, such as GDV syndrome, penetrating abdominal wounds, pyometra, or uncontrolled abdominal hemorrhage, rapid surgical management is necessary for patient survival. This article describes a systematic approach to a small animal patient with acute abdomen.