Changes of abdominal organs in early paragonimiasis are described in dogs and cats. Experimental infection was induced by feeding 40-50 and 20-30 metacercariae of Paragonimus westermani to 15 dogs and 15 cats respectively. These animals were killed sequentially starting from 8 days to 120 days after infection. Complete autopsies were carried out in all animals and the tissues were examined microscopically with the main emphasis on changes of the liver and the diaphragm. A definite bout of acute diffuse fibrinoexudative peritonitis with ascites ranging from 5 to 20 ml was present in both dogs and cats at the time of 20 days after infection. This was also the period of the maximum liver damage and diaphragmatic injuries. The peritonitic changes became minimized after 45 days of infection. The liver changes were of two folds. The first one was characterized by numerous pin-point or linear tissue defects on the surface of the lobes, which were often covered with fibrin clots. Some of these defects were impacted by the larvae. These 'scratch' marks appeared to be of mechanical effect, and the margins were often banal without a significant inflammatory reaction. The scratch marks were no longer observed in animals examined after 45 days. The second was noted in the Kupffer cells of the liver. A large amount of hemosiderin pigment was noted in the Kupffer cells and became prominent by 20 days through 45 days. Hemosiderin-laden macrophages were found also in the spleens of these animals. Some animals in 30 days group showed the most Kupffer cells heavily loaded with hemosiderin. However, no associated degenerative changes were noted in these cells. The diaphragm was quite unique in early phase of infection in all animals examined. Numerous pinpoint perforative lesions could definitely be seen grossly, and some of these lesions included migrating larval worms inside the tunnels. These lesions were microscopically characterized by tract or tunnel formation with accompanying tissue reaction. The diaphragmatic changes were manifest by 20 days after infection. The tracts of tunnels appeared to have been made by pressure necrosis and surrounding edema, and subsequently were associated with a massive eosinophilic influx and myocytolysis. The eosinophilic abscess and multinucleated giant cells were often observed in the animals of the 30 days group. The diaphragmatic changes seemed to be repaired with or without fibrous scar formation which was occasionally seen in 45 days and later.
parasitology-helminth-trematoda ; Paragonimus westermani ; paragonimiasis ; diaphragm ; dog ; cat ; pathology ; peritonitis

The present experimental study was undertaken to observe the chronological change of the worm structure of Clonorchis sinensis and the pathological findings of the liver when this fluke was inoculated to the mouse intraperitoneally. The recovery rate, survival rate, location and size of the inoculated worms as well as the pathological changes of the liver were investigated for the comparison among the groups of mice, classified by number of worms and the duration of experiment. The results obtained were summarized as follows: The recovery and survival rates of the worms decreased especially 28 days after the inoculation. Most of worms (90.l percent) were collected from the peritoneal cavity and some of worms were found tightly adherent to the capsules of the liver, spleen, stomach, intestine and diaphragm. There were no worms recovered penetrated in the parenchymes of these organs. The mean worm size after inoculation was smaller than that before inoculation. At the 10th day after the inoculation, the shrinkage of posterior portion of the worm body was observed. Remarkable atrophy in the reproductive organs of the worm, such as spermatheca, testes, vitelline glands and ovary was frequently observed at the 10th day of inoculation. Histopathologically the liver failed to show any parasitic worm inside the intrahepatic biliary system. However, multiple well formed egg-containing granulomas were present along the liver capsule. These necrotic granulomas were occasionally found under the fibrotic liver capsule. Focal necrosis and focal phlebitis together with vascular dilatation were prominent features seen in the liver. The bile duct in the liver showed mild dilation of the lumen, flattening of epithelial cells and periductal small round cell infiltration. Neither adenomatous hyperplasia nor portal fibrosis was seen in the whole experimental groups. Foci of intralobular micro-granulomas were found in some experimental animals. The worms recovered in the capsule of the liver were degenerated and necrotized. Usually, there were remarkable capsulitis and granuloma formation around the eggs.
parasitology-helminth-trematoda ; Clonorchis sinensis ; pathology ; liver ; spleen ; stomach ; intestine ; diaphragm ; granuoma ; peritoneal cavity

The application of Giemsa technique to stain compressed diaphragm samples obtained from rodents experimentally infected with Trichinella spiralis is described. Diaphragm samples from rats heavily infected with 20 muscle larvae per gram of body weight (20 ML/gbw) were cut into several pieces and stained with Giemsa; on the other hand, whole diaphragms from slightly infected mice (1 ML/gbw) were also stained with Giemsa. Besides, muscle samples were also stained with Giemsa. Observation at 10 x magnification revealed that both ML and nurse cells (NC) look as bluish structures clearly contrasting with the pinkish color of the non-infected muscle fibers. NC in the diaphragms of mice could be easily observed at naked eye as blue points contrasting with the pink surrounding areas formed by the non-infected muscle fibers. Among NC observed in the diaphragms of rats infected with 20 ML/gbw, 4.4% was multiple infection. These findings were confirmed in sectioned and hematoxylin-eosin stained specimens. This data could be usefulness for a rapid diagnosis of trichinellosis in post-mortem mammals without magnification procedures.
Animals ; Azure Stains/*chemistry ; Diaphragm/*parasitology ; Larva/ultrastructure ; Male ; Mice ; Rats ; Rats, Wistar ; Trichinella spiralis/*isolation & purification/ultrastructure ; Trichinosis/diagnosis/*parasitology

The application of Giemsa technique to stain compressed diaphragm samples obtained from rodents experimentally infected with Trichinella spiralis is described. Diaphragm samples from rats heavily infected with 20 muscle larvae per gram of body weight (20 ML/gbw) were cut into several pieces and stained with Giemsa; on the other hand, whole diaphragms from slightly infected mice (1 ML/gbw) were also stained with Giemsa. Besides, muscle samples were also stained with Giemsa. Observation at 10 x magnification revealed that both ML and nurse cells (NC) look as bluish structures clearly contrasting with the pinkish color of the non-infected muscle fibers. NC in the diaphragms of mice could be easily observed at naked eye as blue points contrasting with the pink surrounding areas formed by the non-infected muscle fibers. Among NC observed in the diaphragms of rats infected with 20 ML/gbw, 4.4% was multiple infection. These findings were confirmed in sectioned and hematoxylin-eosin stained specimens. This data could be usefulness for a rapid diagnosis of trichinellosis in post-mortem mammals without magnification procedures.
Animals ; Azure Stains/*chemistry ; Diaphragm/*parasitology ; Larva/ultrastructure ; Male ; Mice ; Rats ; Rats, Wistar ; Trichinella spiralis/*isolation & purification/ultrastructure ; Trichinosis/diagnosis/*parasitology

Diagnosis, Differential ; Diagnostic Errors ; Diaphragm ; diagnostic imaging ; physiopathology ; Echinococcosis, Hepatic ; diagnosis ; pathology ; surgery ; Female ; Hernia, Diaphragmatic ; diagnosis ; diagnostic imaging ; Humans ; Liver ; parasitology ; pathology ; surgery ; Tomography, X-Ray Computed