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Bromide Brucella Slide Agglutination 1319

Bromide
VetBooks.ir Definition Next Diagnostic Steps to Consider Specimen Collection and Handling

Active ingredient in potassium (KBr) or sodium if Levels Are High Serum (red top tube), refrigerate. Submit first
bromide (NaBr), drugs used for treating seizure Lower dosage sample within 1 week of loading dose, second
disorders at 1 month; monitor every 3-6 months. If no
Important Interspecies Differences loading performed, measure after 1 month
Physiology Used primarily in dogs; should be used sparingly and again at 2-3 months for steady-state
The precise mechanism of action in seizure in cats as they are more prone to exhibiting concentration.
control has not been elucidated. It is believed toxic side effects, particularly pneumonitis.
that preferential transport of bromide rather Relative Cost: $$
than chloride across cell membranes results Drug Effects
in neuronal hyperpolarization and depressed Additive sedation if other central nervous Pearls
neuron excitability, and therefore an increased system (CNS) sedatives are used. Diuretics • Older animals, those with other diseases,
seizure threshold. may enhance excretion, increasing bromide and those with renal dysfunction may be
dose required for seizure control. Keep dietary more prone to adverse reactions.
Reference Interval chloride constant during treatment; excessive • Bromides are not approved by the U.S. Food
Target serum concentration range (interpret in chloride can result decrease seizure control, and Drug Administration for use in animals.
conjunction with clinical signs): whereas markedly decreased chloride (in some • Bromide has a small therapeutic window, and
• As sole anticonvulsant: 100-300 mg/dL low-salt diets) can result in toxicosis. serum concentrations should not be used as
• In combination with phenobarbital: 80- sole indicator of toxicity.
200 mg/dL Lab Artifacts
Increase: ion-selective electrode method of AUTHOR: Carrie L. Flint, DVM, DACVP
Causes of Abnormally High Levels measurement (chloride interference) EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
Excessive dosage leads to bromide toxicosis

Brucella Slide Agglutination

Definition immunodiffusion (AGID), tube agglutina- Pearls
ELISA test for detection of Brucella canis tion (TAT), indirect fluorescent antibody test • Humans are susceptible (zoonosis), but
antibody in serum (IFAT), or culture. Appropriate culture samples human B. canis infections are rare. Laboratory Tests
(vaginal exudate, aborted pups, semen) depend • After bacteremia, organisms may concentrate
Synonym on clinical signs and associated available tissues in prostate and epididymis. Agglutination
Rapid slide agglutination test (RSAT) or specimens. titers decline.
• Chronically infected female dogs typically
Physiology Causes of Abnormally Low Levels have recurrent bacteremia and highest titers
Highly sensitive screening test used to detect For the first 3-4 weeks after infection, sero- during proestrus, estrus, pregnancy, or abor-
B. canis infection. Patient serum is mixed with logic test results may be negative even with tion. Testing is suggested at these times.
heat killed B. ovis on slide and evaluated for bacteremia. • The test has a high sensitivity and thus is a
agglutination. reasonable screening test. All breeding dogs
Next Diagnostic Steps to Consider should be tested regularly.
Reference Interval if Levels Are Low • Test result required by some countries (New
Agglutination indicates positive test (patient If exposure or disease is suspected, retesting Zealand, Australia) for entry of dogs. Import
serum contains antibodies to B. canis); serum after 30 days is suggested before admission requirements change and vary, so check for
from noninfected dogs fails to agglutinate. to breeding kennels. Low or intermediate most recent regulations.
titers may indicate previous disease or recent • Infection with other species of Brucella
Causes of Abnormally High Levels exposure. Follow-up blood culture may be besides B. canis may not be detected.
B. canis infection; false-positive test may occur helpful in these animals.
in patients with antibodies to Bordetella bron- AUTHOR: Sharon M. Dial, DVM, PhD, DACVP
EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
chiseptica, Pseudomonas spp., Moraxella spp., or Lab Artifacts
other gram-negative bacteria. Only ≈40% of Gross hemolysis interferes with interpretation.
positive tests are associated with true B. canis
infection. Specimen Collection and Handling
Serum (red top tube), 1 mL; separate serum
Next Diagnostic Steps to Consider from clot; stable at 2-8 °C for four days.
if Levels Are High
Confirm positive test results with 2- Relative Cost: $$
mercaptoethanol tube agglutination, agar gel

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