Absence of immunopathology associated with repeated IV administration of bovine Hb-based oxygen carrier in dogs.

BACKGROUND: A Hb-based oxygen carrier, HBOC-301, is licensed by the FDA for use as a single-dose product to treat anemia in canines. The objective of this study was to investigate the immunopathologic consequences of multiple doses of HBOC-301. STUDY DESIGN AND METHODS: HBOC-301 was administered intravenously at 1.3 g per kg (10 mL/kg) nine times over 50 weeks to each of eight splenectomized beagles. During interim weeks, HBOC-301-specific IgG antibody was quantified in serum by immunoassay. Immunofluorescence studies were performed on thin sections of control and test dog livers and kidneys to detect any IgG, IgM, IgA, or C3 deposition. Physiology (p50) studies evaluated the capacity of circulating HBOC-301-specific IgG antibody to competitively block the binding of oxygen to HBOC-301. RESULTS: HBOC-301-specific IgG antibody was detected in seven of eight HBOC-301-treated dogs by Week 6. Peak antibody levels occurred by Week 10 (after the third dose). Immunofluorescence studies detected comparable IgG, IgA, IgM, or C3 deposition patterns in the kidneys and livers of both control and test dogs, which indicated no selective antibody-mediated deposition from multiple HBOC-301 administrations. Moreover, HBOC-301-specific IgG antibody in serum was unable to inhibit oxygen binding to the HBOC-301 in vitro, which indicated that circulating antibody did not diminish the oxygen-binding capacity of HBOC-301. CONCLUSION: The immunologic, histologic, and physiologic data support the safety of multidose administration of HBOC-301 in canines.

Radiographic, biomechanical, and pathologic effects of hemoglobin glutamer-200 in dogs undergoing cemented total hip arthroplasty.

OBJECTIVE: To determine whether use of hemoglobin glutamer-200 (bovine) as a partial blood volume replacement in dogs undergoing cemented total hip replacement caused any deleterious effects on the bone-cement or cement-prosthesis interface, exerted any deleterious effects on body organs, or caused any complications during the anesthetic, immediate recovery, or long-term recovery period. ANIMALS: 9 adult dogs. METHODS: Dogs were anesthetized, and 15% of the blood volume was removed. Simultaneously, lactated Ringer's solution was infused, and 6 dogs were given hemoglobin glutamer (1 g/kg of body weight, IV). Unilateral total hip replacement was performed. Limb use was assessed visually, and force-plate and radiographic evaluations were performed before, and 8 weeks after, surgery. Eight weeks after surgery, dogs were euthanatized, necropsies were performed, and prosthetic component pullout forces were determined. RESULTS: There were no significant differences between treated and control dogs in regard to biomechanical (visual assessment of gait, force-plate analysis, femoral and acetabular component pullout forces) and pathologic evaluations (physical examination, CBC, serum biochemical analyses, necropsy, and histologic evaluations). Radiographic signs of loosening of the femoral component were seen in 4 dogs treated with hemoglobin glutamer. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of hemoglobin glutamer as a blood substitute did not appear to have any deleterious effects in dogs undergoing total hip arthroplasty. The radiographic findings, which were discordant with the biomechanical results, merit further investigation.

Red blood cell substitutes.

Insufficient supply and risks of homologous blood transfusions have driven the quest for a red blood cell substitute. The recent development of a red blood cell substitute has focused on hemoglobin solutions. The clinical indications for use of a red blood cell substitute in veterinary medicine include blood loss caused by trauma, surgery, or medical causes and other acute anemias. Such a substitute also may have an adjunctive role in radiation treatment and chemotherapy.

Canine leptospirosis. A retrospective study of 17 cases.

Seventeen dogs were diagnosed with leptospirosis on the basis of clinical findings, laboratory abnormalities, and serology. This article summarizes and characterizes the historical and physical findings, laboratory data, serology, treatment, and outcome of these dogs. All of the dogs had serologic evidence of infection with interrogans serovars pomona and grippotyphosa. These findings are compared with previous reports of canine infection with Leptospira interrogans serovars icteroaemorrhagiae and canicola. The clinical presentation of these dogs did not correspond to the classic description of the disease in dogs in which concurrent renal and hepatic diseases are present. This may be due to infection with different serovars than those previously reported. In addition, this article suggests that canine leptospirosis should be considered in the differential diagnosis of dogs with acute or subacute renal failure.