Page 2676 - Cote clinical veterinary advisor dogs and cats 4th

1378 Rabies Diagnostic Testing Relaxin

urine for microbial culture and sensitivity. immediately as leukocytes deteriorate within a bacterial cultures without pyuria, suggestive
of defective chemotaxis.
Consider abdominal ultrasound to evaluate few hours. • Urine dipstick assessment of pyuria is notori-
VetBooks.ir Specimen Collection and Handling Relative Cost: $ (reported as part of ously unreliable in dogs and cats and should
for calculi or neoplasm.
urinalysis)
not be used.
Unless there is a suspected hemostatic
defect or epithelial neoplasm, sterile collec- Pearls AUTHOR: Shannon D. Dehghanpir, DVM, MS, DACVP
EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
tion via cystocentesis is recommended to • Some dogs with diabetes mellitus or
exclude genital tract contamination. Process hyperadrenocorticism may have positive

Rabies Diagnostic Testing

Definition Specimen Collection and Handling • Most testing is done at state diagnostic
Evaluation of presence or absence of rabies Fresh brain tissue. NOTE: Aerosolization of laboratories.
virus infection rabies virus is possible during craniotomy • Half the brain should be submitted in
portion of necropsy or during removal of head formalin to assess for other diseases if rabies
Physiology (exposure of spinal cord). Therefore, removal testing is negative.
Rabies is an acute encephalitis caused by an of head or brain should, ideally, be reserved for • Brain tissue is the only suitable specimen;
RNA virus of the rhabdovirus family. Virus qualified personnel (e.g., pathologist or state other tissues such as whiskers or peripheral
localizes to the central nervous system. Direct veterinarian). Body of rabies suspect should be nerve are not.
IFA testing of brain tissue is used for definitive chilled (refrigerated), not frozen. If practitioner • There are no reliable antemortem tests for
diagnosis. Submission of appropriate specimens must cut the brain, cut in sagittal (longitudinal) rabies virus in animals.
requires necropsy examination. The test detects section. Submit half in clean, dry double bag • Dogs and cats that have an implanted micro-
viral antigen in the neural tissue of infected for IFA test. Clearly label as rabies suspect. chip, are currently vaccinated for rabies, and
animals. Contact the laboratory performing the testing have a suitable titer certified by the FVNA
for appropriate packaging instructions. Laboratory at Kansas State University or the
Reference Interval Veterinary Command Food and Diagnostic
Results are reported as positive or negative. Relative Cost: $$—$$$$ (charges vary Laboratory, Fort Sam Houston, Texas, may
widely among state labs) avoid quarantine when traveling from the
Causes of Abnormally High Levels continental United States to Hawaii or the
Viral infection Pearls United Kingdom if they meet other criteria.
• All personnel who participate in sample For more details regarding pet travel, refer to
Next Diagnostic Steps to Consider collection should have been vaccinated and https://www.aphis.usda.gov/aphis/pet-travel/.
if Levels Are High have a known, adequate vaccination titer.
Exposed personnel should consult their physi- • Personal protective equipment during tissue AUTHOR: Sharon M. Dial, DVM, PhD, DACVP
EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
cians and/or their State Public Health Depart- collection should include heavy rubber
ment immediately. Exposed animals should be gloves, laboratory gown, and waterproof
quarantined and observed for development of apron, boots, surgical masks, protective
clinical signs (p. 861). sleeves, and a face shield.

Relaxin

Definition It may also play an important role in mammary Causes of Abnormally High Levels
Peptide hormone produced by the reproductive development in some species. Additionally, • Pregnancy
tract of many species during pregnancy relaxin is involved in nonreproductive processes • High concentration may persist following
such as fibrosis, wound healing, and protection abortion.
Physiology against myocardial ischemia. • Ovarian cysts in nonpregnant animals
Relaxin may be produced by the corpus luteum
(CL), placenta, or uterus, depending on species Reference Interval Next Diagnostic Steps to Consider
and stage of reproductive cycle. In pregnant • Reported as positive or negative if Levels Are High
dogs, relaxin is initially produced by the CL, • Dogs (pregnant): may be positive as early Evaluate for pregnancy (e.g., ultrasound).
followed by the placenta. It is produced by as 14 days postmating; consistently positive
the placenta in cats. The primary effects of 25 days postmating Lab Artifacts
relaxin occur during implantation and later • Cats (pregnant): may be positive as early as Hemolysis, lipemia may cause false-negative
during parturition. Relaxin promotes uterine, 25 days postmating; consistently positive 31 results.
cervical, and vaginal growth during pregnancy. days postmating

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