Mixed cryoglobulinaemia in a rhesus macaque (Macaca mulatta).

We report cryoglobulinaemia (CG) in a rhesus macaque whose serum sample was gel-like at <37°C and resolubilised upon warming. Mixed CG was diagnosed using serum protein electrophoresis and serum immunofixation electrophoresis. Renal damage and arthrophyma were observed during necropsy. This is the first report of CG in a non-human primate.

Monoclonal immunoglobulin G cryoglobulinemia and multiple myeloma in a domestic shorthair cat.

A 13-year-old castrated domestic shorthair cat was examined because of fever, anorexia, and dermatologic lesions. Crusting, erythema, and well-demarcated purple discoloration of the foot pads and the tips of the pinnae, nose, and tail were seen. A white flocculent precipitate was detected in cooled serum. This precipitate dissolved upon rewarming, consistent with a cryoglobulin. Hypercalcemia, high alanine and aspartate aminotransferase activities, thrombocytopenia, and a monoclonal IgG gammopathy were found. Numerous hepatic nodules were detected by means of abdominal ultrasonography. Cytologic evaluation of fine-needle aspirates of the liver and spleen revealed numerous plasma cells, and evaluation of a bone marrow aspirate revealed plasmacytosis. A diagnosis of multiple myeloma and monoclonal IgG cryoglobulinemia was made, and the cat was euthanatized.

Cryoglobulinemia in a horse.

Cryoglobulin was isolated from a horse which had glomerulo-nephritis and a history of swelling and skin ulcers of the limbs in the winter. The isolated cryoglobulin showed a single peak on a gel permeation chromatography column with an apparent molecular mass (Mr) of 180,000 which could be divided into two gamma bands by cellulose acetate electrophoresis. Immunoelectrophoretic analysis revealed that the cryoglobulin formed two precipitation lines with anti-horse IgG. Spur formation was observed when the cryoglobulin and the IgG purified from a normal healthy horse were cross-reacted with anti-horse IgG on a double diffusion gel. In addition, sodium dodecyl sulfate-polyacrylamide gel electrophoresis under the reduced conditions showed that the isolated cryoglobulin consisted of two doublets of polypeptides with Mr values of 52,000 and 50,000, and 31,000, and 30,000, corresponding to the heavy chain and the light chain of the horse IgG molecules, respectively. These results suggest that the isolated cryoglobulin might consist of two different IgG molecules, and that the manifestations such as foot swelling with skin ulcers and renal failures were all induced by the cryoglobulin in the serum.

Some unusual features of mesangioproliferative glomerulonephritis in horses.

Seven horses ranging from three to 15 years of age had nephrotic syndrome; at necropsy, renal tissue of all seven horses had the morphologic lesions of mesangioproliferative glomerulonephritis (membranoproliferative glomerulonephritis). Homogeneous eosinophilic material which filled the glomerular capillary lumina was found in five horses. Ultrastructurally, this material primarily consisted of electron-dense deposits with a fibrillar pattern in five horses and in one horse, rhomboid crystalline deposits which resembled deposits seen in human cryoglobulinemia. The association of mesangioproliferative glomerulonephritis with cryoglobulinemia is well documented in man. The presence of intracapillary deposits, with the histologic and ultrastructural lesion of mesangioproliferative glomerulonephritis, suggests a similar association in these horses.