Systemic oxalosis in a free-ranging green turtle (Chelonia mydas)

A female juvenile green turtle (Chelonia mydas), found alive in Guanabara Bay, Rio de Janeiro, Brazil, was weak, dehydrated and cachectic, with a healed fracture in the caudal portion of the carapace. Despite supportive treatment, the animal died after 9 days. At necropsy the main lesions were pallor of visceral organs, arthritis and deposits of whitish granular material in the wall of large arteries and the trachea. Histopathological analysis revealed mild to severe deposition of crystals, consistent with calcium oxalate, in both kidneys and the spleen, heart, small intestine, pancreas, thymus and salt gland, as well as bacterial meningitis, septic arthritis, spirorchidiasis and a fibropapilloma on the nictitating membrane. The main pathological findings were suggestive of septic shock, mainly due to the bacterial meningitis and septic arthritis, with systemic oxalosis and spirorchidiasis as contributing lesions. Although renal oxalosis has been described in green turtles as an incidental finding, presumably due to ingestion of oxalate-containing plants, this turtle had an unusual systemic deposition of oxalate crystals.