The nephrotic syndrome in a heifer due to glomerulonephritis

An 18-month-old Friesian heifer, which was admitted in November with a history of weight loss, diarrhoea and submandibular oedema, was found to have an enlarged left kidney and a massive proteinuria. Laboratory investigations revealed that there was a marked hypoalbuminaemia and that the range and the proportions of the individual proteins in the urine were almost identical to those in the serum. Consequently, the nephrotic syndrome was diagnosed. On gross and histopathological examination of the kidneys, there was evidence of pyelonephritis. However, immunofluorescence studies revealed a striking diffuse deposition of immunoglobulin in a predominantly linear pattern along the glomerular basement membranes. Abnormalities of the basement membranes. Abnormalities of the basement membranes were seen on ultrastructural examination and evidence of a flomerular protein leak was detected but changes typical of immune-complex deposition were absent. The immunofluorescence findings suggested a diagnosis of glomerulonephritis mediated by antiglomerular basement membrane antibody.