Atherosclerosis in a Parrot
NECROPSY REQUEST
CLINICAL DIAGNOSIS:
Died suddenly - cardiac arrest.
HISTORY: CC - seizures for the last two years. Has been treated
HPI for chlamydia at about six months of age and again 16 months later (injectable
Vibramycin senes). Seizures were described as an episode of panting
followed by the parrot closing his eyes and losing his balance. One leg
would slide off of perch, get rigid and move slightly. He never fell
off perch. He regurgitated when seizures would start. Tests for
Chlamydia never came back positive, he was treated based on signs
(yellow feces, lethargic, not playing). Seizures lasted 15 minutes
(says owner). The parrot lived with another bird and we would like
results as soon as possible to reassure owner her other bird is not in
danger. We are not convinced that he had seizures, we are leaning more
towards congenital heart disease.
PE - NAF except he looked a little subdued before our exam. Exam was
short, and non stressful. The parrot arrested shortly afterwards.
CLINICAL QUESTIONS: Atherosclerosis; heart disease; other cause
of epileptiform seizures.
NECROPSY GROSS REPORT
ANIMAL
IDENTIFICATION:
A 0.38kg, two-year-old, male, green parrot is presented for necropsy in good
body condition.
CARDIOVASCULAR (Heart weight: 12g. The right ventricular free wall is
1mm in width. The left ventricular free wall is 3mm in width.): The
brachiocephalic arteries, carotid arteries, and subclavian arteries are
markedly thickened (up to approximately 2mm) and yellowish-white (severe
atherosclerosis).
INTEGUMENTARY AND SPECIAL SENSES, RESPIRATORY, HEMIC AND
LYMPHATIC, URINARY (Right kidney weight: 2g; Left kidney weight:
2g), GENITAL, LIVER AND PANCREAS (Liver weight: 8g),
DIGESTIVE, ENDOCRINE, MUSCULOSKELETAL, NERVOUS: No
significant lesions observed.
POSTMORTEM ANALYSIS AND DIAGNOSIS: The gross findings are
consistent with severe atherosclerosis, which can result in brain ischemia and
sudden death. There is no evidence of congenital heart disease.
TENTATIVE DIAGNOSIS: Atherosclerosis.
.JPG)
(Fig.1 The brachiocephalic and carotid arteries dorsal to the heart are markedly thickened)
.JPG)
(Fig. 2 The heart after removal, showing the thickened arteries)
NECROPSY HISTOPATHOLOGY REPORT
MICROSCOPIC LESIONS:
Coronary arteries,
Brachiocephalic arteries, Carotic arteries, Aorta: Severe, diffuse, chronic
atherosclerosis, with chondroid metaplasia.
Heart: Mild, multifocal, chronic, myocardial degeneration and necrosis, with
fibrosis.
Spleen, Kidney: Mild to moderate, multifocal, chronic atherosclerosis.
Skeletal muscle (pectoral): Mild, multifocal, chronic atherosclerosis.
Liver, Proventriculus, Ventriculus, Small intestine, Cecum, Pancreas: No
significant findings.
DIAGNOSIS: Atherosclerosis.
.JPG)
(Fig. 3 Microscopic view of an affected artery. Note the severe expansion of the tunica intima by large foamy macrophages. The lumen of the vessel is narrowed (arrow))
.JPG)
(Fig. 4 Microscopic view of the aorta, showing the marked thickening of the vessel wall)
.JPG)
(Fig. 5 Higher magnification (40X) of the aorta, showing the tunica intima expanded by a large number of vacuolated, lipid-laden macrophages (thin arrow). Cartilage formation is also evident (thick arrow))
INTERPRETIVE SUMMARY/COMMENTS:
Atherosclerosis with secondary ischemia is the probable cause of death. There
is no evidence of infectious disease.
