Heartworm Flashcards
What are the different tests for heartworm
Snap test, difil, buffy coat, knotts test, direct smear, direct drop
What does the difil test concentrate on?
Microfilaria
What does the difil test use?
Whole blood, at least one cc
How do you perform a difil test?
Add lysing solution to lyse, the red blood cells(nine parts lyse, one part red blood cells), pass blood solution through a filter, place filter on slide, apply stain in cover slip and examine for microfilaria
How do you perform a direct smear?
Make a blood smear, stain, examine for microfilaria
How do you perform a direct drop?
Play single drop of blood onto microscope line immediately after collecting, add cover slip, examine under 10 X for movement among the red blood cells
What test is often unreliable unless large parasite burden
Direct drop
How do you perform a Buffy coat examination?
Fill two high micro hematocrit tubes, spin at appropriate speed in time, examine Buffy coat directly through PVC tube under 10 X
What is an occult infection
Antigen test is positive, but no circulating microfilaria are found in the blood
What situations might be happening in an occult infection
Adults may be of 1 sex only
Immature adults
Adults are dead, but antigen has not been cleared
Immune mediated clearance of microfilaria
Monthly heartworm prevention
Improper handling of sample/lab error
What is an imitator of dirofilaria
Acanthocheilonema
What does DEA stand for?
Dog erythrocyte antigen
What are the two types of canine blood?
1.1, 1.2
Dogs that are DEA 1.1 positive can be considered to be
Universal recipients
Dogs that are DEA 1.1 negative can be considered to be
Universal donors
What is the most important canine blood type?
1.1
What percent of greyhounds are considered DA 1.1 negative
60%
What breeds are typically universal donors?
Boxers, Irish wolfhound, German shepherds, Dobermans, pitbull’s, greyhounds
What breeds of dogs are more commonly DEA 1.1 positive
Golden retrievers and labradors
Our naturally occurring anti-DEA 1.1 antibodies known to exist
No
What may happen if GA 1.1 positive blood is given to a DA 1.1 negative dog
No immediate reaction, however, antibodies may develop and result in a delayed transfusion reaction within one week of the original mismatch transfusion
What are the feline blood types?
A, B, AB
What do you type a A and B cats have
naturally occurring antibodies to the opposite blood type
What type of blood are most of the cats in the United States?
Type a
Type b cats are most likely to be
Purebred
True or false: few cats have AB
True
Transfusing ___________ cats with__________ may result in serious transfusion reactions, and even death
Type B, type a
What cats are universal recipients?
Type AB
Why do we cross match blood?
RBC’s have antigens found on their surface. They can react to antibodies found in blood of other animals.
True or false: antigen – antibody reactions can occur with an with blood transfusions of different blood group antigens between donors and recipients
True
What are the reactions that occur?
Agglutination of RBC‘s, lysis of RBC
What is the major cross match?
Donor RBC and recipient serum
What is a minor cross match?
Recipient RBC and donor serum
What is step one of cross matching?
2EDTA tubes of blood one is donor one is recipient 2SST tubes of blood one is donor one is recipient center huge tubes at 3000 RPM for 10 minutes. Pippette that off serum from donor and put it in RTT labeled donor serum pipette off serum from recipient and put an RTT.
What is step two to cross matching
Wash red blood cells from EDTA tubes three times and 4 to 5 mils of saline mix well centrifuge at five minutes at 3000 RPM. Remove saline and discard leaving plate of red boat cells at bottom tube repeat two more times done for both the donor and recipients red blood cells separately.
What is what is step three of cross matching
Spend RC pellet with saline to make sure a 2 to 5 RBC suspension one drop of RBC and 20 drops of saline prepare three plain RTT tubes, labeled major minor and recipient control
What is step four of cross matching?
To the major tube and two drops recipient serum and one drop donors RBC to the minor tube add two drops donor serum and one drop our recipient RBC to the control tube add two drops recipient serum and one drop recipient RBC
What is step five of cross mansion?
Mix gently and incubate for 15 to 20 minutes at 37°C in a warm water bath centrifuge all samples at 3000 RPM for one minute
What does slight homolysis infer
Nonspecific
What does significant hemolysis infer?
Incompatibility, necessity of choosing another donor
What is step six of cross matching?
Place a drop of crossmatch blood on a slide and examine it at 40 X for agglutination
What does evidence of agglutination infer?
Unsuitable donor
True or false: a compatible blood cross match does not prevent sensitization or delay transfusion fusion reactions, it simply indicates that at the present time no detectable antibodies against the RBC’s exist
True
What are blood donation programs?
University of Georgia blood donations program
Ohio State University animal blood bank
AHDC transfusion guidelines
