Enzootic hematuria is a syndrome in mature cattle characterized by persistent hematuria and anemia, associated with hemorrhages or neoplasm in the lower urinary tract. The syndrome is attributed to chronic ingestion of bracken fern and it appears to be a link between bracken fern and bovine papilloma virus.

Material and method

The urinary bladders from 13 cattle, slaughtered in the north of Transylvania after persistent hematuria, were examined macroscopically by the authors. Samples from bladder mucosa and kidneys were taken and processed for light and electron microscopy.

Results

Morphological changes were dominated by hemorrhages into the urinary bladder wall. In most cases, hematuria originates from petechial, ecchymotic or suffusive hemorrhages in the urothelium of the bladder, rarely from renal calices. Ectasia and engorgement of capillaries was present in the bladder and these altered vessels were the major source of the hemorrhagic syndrome. A great number of lymphocytes were present in the hemorrhagic areas. In rare cases, the hemorrhage originates from ulcerated neoplasm.

The earliest epithelial lesions consisted in vacuolar degeneration, later hyperplastic and metaplastic (squamous) changes occurred in the urothelium accompanying the described vascular lesions. In our opinion, these features are preneoplastic changes. In the same areas, the ultra structural study showed changes in discoid vesicles shape, junction alteration with dilatation of junction regions, thickening or fragmentation of the basal lamina. Severe hyperemia, edema and infiltration with lymphocytes, plasma cells and histiocytes were also identified.

In two cases the cavernous hemangioma was the single type of well developed mesenchymal neoplasm, in one case a sarcomatous transformation was present in the bladder wall.

Several types of epithelial neoplasm were present, both in pure form and in combination: papilloma or fibropapilloma in 6 cases, pseudocarcinous carcinoma in 5 cases, squamous cell carcinoma in only one case. Mammary fibropapillomas were present in one case, with carcinoma and hemangioma in the bladder.

The lesions in the kidneys were granular and hyaline degeneration in the tubular epithelium, edema and PAS-positive deposits in the interstitium, mineralization of the tubules and hyperplasia of the collecting ducts.

Conclusions

The enzootic hematuria syndrome is associated with hemorrhages or neoplasm in the lower urinary tract.

References

1.  Baba A.I.; 1996: Diagnostic necropsic veterinar, Ed,. Ceres, Bucharest.

2.  Ghergariu S.; 1992: Biol. An. de Lab., 19:578-82.

3.  Jubb K.V.F. et al; 1993: Pathology of Domestic Animals, Academic Press.