Trophoblast Emboli in a Chinchilla
History: An 8-11 month old female intact Chinchilla had given birth to 3 baby Chinchillas 2 weeks prior. Without any premonitory signs she “had a spasm, fell to the side and died ½ hour later”.
The lungs were mottled red and pink, wet and heavy. The right cranial lung lobe was most affected.
The uterine horns contained three ½ cm round white foci that expanded the uterine wall consisting of a semi-soft material (involution of placental sites).
Lungs: There was diffuse congestion, and multifocal suppurative bronchopneumonia with edema and hemorrhage filling alveoli. There were multifocal alveolar capillaries with 100-200 um trophoblast cells occuring singly or multiply. The cells had abundant cytoplasm and 50-100 um diameter nuclei. Trophoblasts were present in normal lung as well as pneumonic lung.
Uterus: Trophoblasts were present within blood vessels of the myometrium in the uterus.
PAS staining has been used to outline the basement membranes of the alveolar cappillaries to demostrate the intravascular nature of the trophoblast emboli.
The cause of death was attributed to pneumonia. Most trophoblast emboli were present in areas with no inflammation. In other reports of this condition in hamsters, chinchillas, and porcupines these are considered incidental findings. In humans they have been linked to life threatening conditions. Hemochorial placentation is common to all these species.
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