Toxoplasmosis in a free ranging hairy dwarf porcupine ( Sphiggurus
spinosus) with a novel genotype
Abstract
Toxoplasmosis is a zoonotic disease caused by the ubiquitous coccidia
Toxoplasma gondii. Rodents play an important role in maintaining
its life cycle, as they are one of the main diet sources for felids
(wild and domestic), the unique definitive hosts. However, reports of
toxoplasmosis in porcupines (Rodentia Order) are uncommon, with gaps
concerning its pathophysiology. South America is the continent with the
greatest genetic diversity of rodents and T. gondii. A
free-ranging hairy dwarf porcupine was admitted to a wildlife rescue
center with a history of trauma. During rehabilitation, the animal
presented neurological symptoms (sporadic episodes of hind limbs
paresis) and died five months later. The main findings during necropsy
were brain congestion and severe incisor overgrowth associated with
maxillary perforation. The histopathological exam showed moderate
encephalitis, with variable-sized round cysts, positive for PAS stain
and immunohistochemistry for T. gondii. Additionally, two cysts
were observed in the medulla of the adrenal gland. Molecular techniques
were performed to characterize the parasite load by qPCR (Cq=30) and the
genotype by PCR-RFLP with 11 markers, which revealed a new genotype.
This case adds to the body of knowledge in comparative pathology of
Neotropical Rodentia and reports a new genotype circulating in South
America.