Neonatal isoerythrolysis Flashcards
When does neonatal isoerythrolysis occur
Neonatal isoerythrolysis occurs when Type-A or Type-AB kittens are born to Type-B queens
- high titers of anti-A antibodies pass from the queen to the kittens in the colostrum
- not transplacentally, as the feline placenta is an endotheliochorial type that only allows very small amounts of maternal antibodies to pass to the kitten in utero
The colostral anti-A alloantbodies are absorbed into the blood stream and then cause acute intravascular and/or extravascular hemolysis in affected kittens
What are the clinical signs observed in kittens suffereing neonatal isoerythrolysis
Clinical signs observed in affected kittens:
- letahrgy and weakness
- pallor due to anemia
- icterus
- hemoglobinuria
- hyperbilirubinuria
- sudden death (i.e., fading kittens)
- necrosis of the tail tip (presumably due to cold-agglutinins) at around 3 weeks of age in more mildly affected kittens
Kittens with mild neonatal isoerythrolysis may be clinically normal
How can you make a diagnosis of neonatal isoerythrolysis
The diagnosis is highly suggested by the timing of the clinical signs
Confirmation requires blood typing of the queen and affected kittens
The kittens will also have a positive Coomb’s test
What would be your treatment plan for kittens affected by neonatal isoerythrolysis
Type A or AB kittens should be removed from their mother as soon as the condition has been detected
- or earlier is the birth is to a known Type-B female and Type-A or AB male
Kittens may be supplemented with commercial milk replacement, or be placed with a foster Type-A queen if possible
- they can be replaced on their mother after 24 hours, as the basorption of maternal antibodies across the gut is minimal by that stage
Severely anemic kittens should receive 2-3 ml of washed RBCs during the first 3 days
- the ideal donor at this stage is the mother (as the antibodies will not react to her own RBCs)
- the blood can be administered via a 25-18 G spinal needle into the bone marrow cavity of the kitten’s femur via the trochanteric fossa
- after day 3 of life, a washed Type-A blood transfusion should e considered if the kitten requires another blood transfusion as it will now be forming its own anti-B alloantibodies
How could you correct the lack of colostrum when fostering newly born kittens
Protective immunoglobulins would normally be obtained via colostrum in the first 16 hours of life
This can be circumvented by the parenteral administration of 70-150 ml/kg of type-matched (type-A in this instance) adult serum
- although kittens seem to do OK even if this not administered
Describe the washed RBCs protocol
To wash the RBCs, 2-3 ml of donor blood is collected in an EDTA tube and centrifuegd
Discard the supernatant
Add twice the volume of sterile isotonic saline to the RBCs
Gently agitate and centriguge again
Discard the supernatant and repeat
After discarding the final supernatant, add an equal volume of slightly warmed sterile isotoni saline and administer to the patient
What is an important recommendation for breeders to prevent neonatal isoerythrolysis
It is recommended that all breeding cats should be blood typed priori mating
Type-A and Type-AB males should not be bred with Type-B females
Type-B males can be bred with any type of females
