FINAL DIAGNOSIS - Pancreatic eurytremiasis
Signalment: 4-year-old male neutered Domestic
shorthair cat
Clinical history: The cat was presented to the
referring veterinarian with an 8-month history of heart
murmur, chronic weight loss and diarrhea. No cardiac abnormalities
were observed on ultrasound.
The reported history indicated that the cat had a good
appetite but failed to gain weight. A day prior to death,
the cat had presented with acute onset of severe depression
and central blindness. Chest auscultation revealed only
a slight murmur, and no abnormal lung sounds. Clinical
pathology revealed slightly elevated albumin, mild normocytic
anemia, neutropenia, lymphopenia and eosinophilia. The
cat was given supportive therapy but died the next day.
Gross Findings: At necropsy, the pancreas was diffusely
atrophic and had extensive loss of normal lobular architecture.
Other gross lesions observed included a thickened left ventricular
wall and a pale mottled liver. The small intestine was
dilated and gas-filled.
Histopathologic Findings: Histologically, the pancreas
was markedly atrophied. The glandular architecture was
effaced and replaced by thick bands of fibrous connective
tissue that was infiltrated by eosinophils, fewer epithelioid
macrophages, and lymphocytes. Remaining acinar cells were
small and lacked acidophilic granules. Within an enlarged
pancreatic duct in the section were several 25x40 microns
trematode ova. Ova had thick brownish-yellow shells, a
single operculum, and contained meracidia. A section of
an adult trematode, characterized by a pink tegument, cross
sections of a uterus, testis and intestinal tract, was also
within the duct. The ductal wall was hyperplastic and markedly
infiltrated by several eosinophils, macrophages and lymphocytes.
Identification of trematodes as Eurytrema
procyonis was made on paraffin-embedded tissues.
Morphologic Diagnosis:
1) Pancreas: Granulomatous, eosinophilic pancreatitis with
marked atrophy and fibrosis
2) Pancreatic duct: Granulomatous, eosinophilic inflammation
with intraductal trematode and ova (Eurytrema procyonis)
Discussion: The fluke Eurytrema procyonis
was first described in the raccoon pancreas by Denton
in 1942 in Houston.
Since then, reports of its occurrence in the pancreatic
duct of foxes, cats and other species have appeared. The
primary habitat of these flukes is the medium pancreatic
ducts, although they may simultaneously infest the biliary
tract. Infestations of the pancreatic duct causes distention,
thickening of the ducts, and chronic interstitial pancreatitis,
leading to periductal and acinar fibrosis.
Significant loss of exocrine pancreatic function as compared
to uninfected cats has been demonstrated by functional studies
on the pancreas of infected cats. Impaired bicarbonate
and protein secretions were observed in these cats, even
in the absence of clinical manifestation of pancreatic insufficiency.
The exocrine pancreas function of the cat in this report,
however, was not evaluated. The slightly elevated albumin
observed was most likely a spurious increase resulting from
dehydration. Severe atrophy and fibrosis of pancreas is
most likely a result of chronic obstruction and not direct
effects of the flukes.
The life cycle of E. procyonis is believed to
involve ingestion of the intermediate host (snail, grasshopper).
Outdoor cats are therefore at a higher risk, especially
in rural and semirural areas.
-byVictoria
Owiredu-Laast, DVM
ADDL Graduate Student
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