Romiplostim as Adjunctive Treatment of Refractory Amegakaryocytic Immune Thrombocytopenia in a Dog.

A 9-year-old, intact male, mixed-breed dog was admitted with a 3-day history of severe thrombocytopenia and bleeding diathesis. Physical examination revealed mucosal and cutaneous petechiae and ecchymoses, melena, and gross hematuria. Clinicopathologic evaluation indicated severe thrombocytopenia, anemia, and panhypoproteinemia. Serology for common endemic vector-borne pathogens was negative and thoracic and abdominal imaging was unremarkable. Bone marrow aspiration cytology revealed aplasia of the megakaryocytic lineage, in the context of a mildly hypoplastic myeloid and a normal erythroid series. A diagnosis of presumptive primary amegakaryocytic immune thrombocytopenia (ITP) was established. Treatment with vincristine, prednisolone, and mycophenolate mofetil along with several whole blood transfusions failed to achieve clinical and clinicopathologic remission. As an adjunct treatment, romiplostim was administered at a cumulative dose of 15 µg/kg, subcutaneously, in 2 sessions, 1 week apart, and complete clinical and hematological remission was noted 8 days postinitiation of romiplostim. Thirty-eight months later, the dog remains clinically healthy with no evidence of hematological relapse. Romiplostim could be a promising adjunctive treatment option in dogs with refractory ITP.

Presumptive Lornoxicam Intoxication in Four Dogs.

Lornoxicam is a nonsteroidal anti-inflammatory drug extensively used in human medicine, which is not approved for canine use. Lornoxicam intoxication has been rarely reported in dogs. Four dogs of various breeds, aged 7 months to 10 years, were admitted with a recent history of melena, anorexia and depression, occurring 1-4 days after the ingestion of lornoxicam (dose range: 0.53-2.7 [median 1.17] mg/kg). No clinically relevant comorbidities were documented, but low doses of prednisolone had been given in 3 of the dogs, in close temporal association with lornoxicam. Major clinical and clinicopathologic findings on admission included mucosal pallor, melena, depression, severe anemia, neutrophilic leucocytosis, and panhypoproteinemia. Perforated pyloric and duodenal ulcers were documented in 3 dogs by exploratory celiotomy or postmortem. Prolonged hospitalization (5-20 days) with extensive supportive care and multiple blood transfusions was required in 3 of the 4 dogs who survived to discharge. Lornoxicam ingestion may cause protracted and severe gastrointestinal tract injury and bleeding, blood loss anemia, panhypoproteinemia, and perforated gastrointestinal ulcers, associated with significant morbidity and mortality in dogs.