title: Histopathological changes of Macaca mulatta infected with Plasmodium knowlesi.
abstract: OBJECTIVE
  To study the histopathological changes of relevant internal organs of Macaca mulatta infected with Plasmodium knowlesi (P. knowlesi).
  
  
  METHODS
  Histopathological examination of 3 monkeys who died of P. knowlesi infection, 2 P. knowlesi infected monkeys who died of treatment failure with artesunate suppository and 1 P. knowlesi infected monkey that was cured by piperaquine phosphate (PQP) but died of trauma and necrosis of the fore limb.
  
  
  RESULTS
  The heart, liver, spleen, lung, kidney, brain, pancreas, parathyroid, pituitary and lymph nodes showed severe pathological changes in 3 monkeys (No. 1, 7 and 12) who died of P. knowlesi infection and 1 infected monkey (No. 72) who died of treatment failure with artesunate suppository. Red blood cells containing malarial parasites and pigments were concentrated in the capillaries of these organs. Malarial pigments were deposited in many organs or phagocytized by macrophages in 1 monkey (No. 131), it was cured by piperaquine phosphate but died of trauma and necrosis of the fore limb; cellular atrophy and disappearance of pancreatic islets, parathyroid and pituitary cells were also observed. One monkey (No. 33) treated with artesunate suppository, showed that blood parasites became negative but recrudesced and pituitary later died from a gavage accident. Its organs showed a significant difference to those of the infected monkeys receiving no treatment. Only the liver Kupffer cells and cerebral matrix contained malarial parasites and pigments; many relevant internal organs showed repair.
  
  
  CONCLUSIONS
  The pathological changes of relevant internal organs of Macaca mulatta infected with P. knowlesi were examined in detail, especially cellular atrophy and the disappearance of pancreatic islets, parathyroid and pituitary cells and myolysis of cardiac muscles. These changes have not previously been reported elsewhere.
authors.affiliation: Department of Malaria, Institute of Tropical Medicine, Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.forename: G
authors.initials: G
authors.lastname: Li
authors.forename: Y
authors.initials: Y
authors.lastname: Lu
authors.forename: Z
authors.initials: Z
authors.lastname: Luo
mesh_terms: D000818:Animals; D037621:Artemisinins / Q000008:administration & dosage; D000077332:Artesunate; D008253:Macaca mulatta; D008288:Malaria / Q000188:drug therapy / Q000473:pathology / Q000662:veterinary*; D008992:Monkey Diseases / Q000188:drug therapy / Q000473:pathology*; D016790:Plasmodium knowlesi; D011804:Quinolines / Q000627:therapeutic use; D012717:Sesquiterpenes / Q000008:administration & dosage; D013488:Suppositories; D010879:Piperazines
chemical_list: D037621:Artemisinins; D000077332:Artesunate; D011804:Quinolines; D012717:Sesquiterpenes; D013488:Suppositories; C034759:piperaquine; D010879:Piperazines