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Mycoplasma spp Culture Myoglobinemia, Myoglobinuria 1367

Drug Effects used; label as biohazard. Submit to laboratory • Fine-needle aspirates of solid tissue lesions
Concurrent or recent antibiotic therapy may as soon as possible and warn lab of suspected are characterized by macrophages containing
VetBooks.ir Lab Artifacts Relative Cost: $$ images with Wright-Giemsa or Diff-Quik
rod-shaped organisms that appear as negative
diagnosis.
inhibit growth.
stains.
Contamination or overgrowth by commensal
• PCR testing for detection of DNA is available
organisms may mask growth. Pearls • Organisms will stain with acid-fast stains.
• Cutaneous or localized infections are more for some of the zoonotic strains of Mycobac-
Specimen Collection and Handling likely to become systemic in immuno- terium spp., but culture and susceptibility
Tissue or exudate from lesion in a sterile compromised hosts. Immunocompromised testing remain the gold standard.
container. If zoonotic Mycobacterium spp. are owners may be more susceptible to zoonotic
suspected, the container should have a screw infection. AUTHOR: Sharon M. Dial, DVM, PhD, DACVP
EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
top and a double outer container should be

Mycoplasma spp Culture

Definition Next Diagnostic Steps to Consider Laboratory should be contacted to obtain media
Laboratory growth of infectious Mycoplasma spp if Levels are High for sample submission.
agents for isolation and identification See pp. 199, 438, and 987.
Relative Cost: $$
Physiology Causes of Abnormally Low Levels
Mycoplasma spp are the smallest, simplest Overgrowth of other organisms; improper Pearls
self-replicating bacteria. These organisms handling or culture conditions; prior use of • Mycoplasmal conjunctivitis and respiratory
are fastidious and grow slowly in culture, so antimicrobial drugs; uninfected animal disease are more likely to occur in cats;
confirmation of infection is often made via arthritis is more likely to occur in dogs. Co-
more rapid PCR testing instead of bacterial Drug Effects infection with other pathogens is common
culture. A subset of potential pathogens known Glucocorticoid or other immunosuppressive in Mycoplasma infection.
as hemotropic Mycoplasma spp (previously called therapies may enhance culture recovery of • Growth in culture may take up to 2 weeks;
Haemobartonella spp) may be associated with organism. Antimicrobial drugs that act by serologic tests or PCR is more commonly
hemolytic anemia, but bacterial culture is rarely means other than cell wall inhibition impede used for disease diagnosis.
used for disease confirmation. culture. • Culture is rarely used for documentation
of hemotropic Mycoplasma; microscopic
Reference Interval Lab Artifacts visualization of organisms and/or PCR is
Reported as no growth or growth with identi- Contamination with commensals may mask used instead. Laboratory Tests
fication of pathogens; Mycoplasma growth may growth. Organism grows slowly in culture,
or may not be speciated, depending on the and cultures may be discarded inadvertently AUTHOR: Sharon M. Dial, DVM, PhD, DACVP
EDITOR: Lois Roth-Johnson, DVM, PhD, DACVP
laboratory used. if laboratory personnel are not informed that
Mycoplasma spp infection is suspected.
Causes of Abnormally High Levels
Infection is associated with upper/lower Specimen Collection and Handling
respiratory disease, conjunctivitis, arthritis, and Swabs, exudate, or tissue should be submitted
hemolytic disease (hemotropic Mycoplasma spp). in specific transport media to enhance growth.

Myoglobinemia, Myoglobinuria

Definition passes quickly through the glomerulus and is Causes of Abnormally High Levels
Myoglobin is a low-molecular-weight heme excreted in urine. Red to brown urine discol- Trauma, ischemia, toxic injury, or necrosis of
protein found in muscle tissue. oration due to myoglobinuria occurs before muscle tissue
plasma discoloration. Myoglobinuria causes
Physiology a positive occult blood test result on a urine Next Diagnostic Steps to Consider
Myoglobin stores and transports oxygen dipstick. if Levels are High
in muscle fibers. It is released from muscle Evaluate for muscle injury or necrosis (e.g.,
when there is severe disruption of the muscle Reference Interval serum creatine kinase level) versus laboratory
membrane or necrosis. Myoglobin is detected Serum myoglobin in dogs: < 10-13.6 ng/mL. evidence of hemolysis.
in the serum 2-4 hours after injury. It does Cats: < 10-13.8 ng/mL. Not present in urine
not significantly bind serum proteins. It of healthy animals

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