Case Description—A 6-year-old castrated male Llewelyn Setter was evaluated because of an acute onset of myalgia and respiratory distress.
Clinical Findings—Physical examination revealed a stiff stilted gait, swollen muscles that appeared to cause signs of pain, panting, and ptyalism. The dog had a decrease in palpebral reflexes bilaterally and a decrease in myotatic reflexes in all 4 limbs. The panniculus reflex was considered normal, and all other cranial nerve reflexes were intact. Serum biochemical analysis revealed markedly high cardiac troponin-I concentration and creatine kinase and aspartate aminotransferase activities. Urinalysis revealed myoglobinuria. Results for thoracic and abdominal radiography, blood pressure measurement, and an ECG were within anticipated limits. Echocardiographic findings were consistent with secondary systolic myocardial failure. Arterial blood gas analysis confirmed hypoxemia and hypoventilation. The dog had negative results when tested for infectious diseases. Examination of skeletal muscle biopsy specimens identified necrotizing myopathy.
Treatment and Outcome—Treatment included ventilatory support; IV administration of an electrolyte solution supplemented with potassium chloride; administration of dantrolene; vasopressor administration; parenteral administration of nutrients; use of multimodal analgesics; administration of clindamycin, furosemide, mannitol, and enrofloxacin; and dietary supplementation with L-carnitine and coenzyme Q10. Other medical interventions were not required, and the dog made a rapid and complete recovery.
Clinical Relevance—Necrotizing myopathy resulting in rhabdomyolysis and myoglobinuria can lead to life-threatening physical and biochemical abnormalities. Making a correct diagnosis is essential, and patients require intensive supportive care. The prognosis can be excellent for recovery, provided there is no secondary organ dysfunction.
Case Description—A 20-year-old sexually intact female African Grey parrot (Psittacus erithacus) was evaluated to determine the cause of lethargy, hyporexia, weight loss, and persistent ascites of 21 days' duration.
Clinical Findings—Physical examination revealed a markedly distended abdomen and systolic heart murmur. Thoracic radiography revealed cardiomegaly and hepatomegaly. Doppler echocardiography revealed severe eccentric and concentric hypertrophy of the right ventricle with systolic dysfunction, moderate regurgitation through the right atrioventricular valve, a substantial increase in estimated systolic pulmonary arterial pressure, hepatic venous congestion, and coelomic effusion. A clinical diagnosis of chronic cor pulmonale was established.
Treatment and Outcome—The parrot was initially stabilized by use of coelomocentesis. During the next month, the parrot was treated by administration of furosemide, hydrochlorothiazide, spironolactone, benazepril, and pimobendan. The parrot appeared to be responding well to treatment but was found dead in its cage 35 days following initial examination. Postmortem examination revealed substantial atherosclerosis of the large pulmonary arteries, with lesions extending into the medium-size arteries. Pulmonary atherosclerosis was suspected as a cause of the severe pulmonary hypertension.
Clinical Relevance—Although atherosclerosis most commonly affects the systemic and coronary arteries of parrots, sclerotic changes within the pulmonary vasculature should be considered as a possible cause of pulmonary hypertension and as a differential diagnosis for right-sided congestive heart failure in psittacine species.