Page 147 - Small Animal Clinical Nutrition 5th Edition

148 Small Animal Clinical Nutrition

VetBooks.ir CASE 6-11

Cachexia in a Young Giant Schnauzer

Patient Assessment
A five-month-old female giant schnauzer was admitted for lethargy, depression and cachexia (body condition score 1/5). The dog
weighed 7.8 kg and was 47 cm high at the shoulder. It had gained no weight in the previous eight weeks. The dog’s four normal
female littermates weighed 20.5 to 22.5 kg and were 48 to 52 cm high at the shoulder.
Hematologic abnormalities included chronic nonregenerative anemia and neutropenia. Peripheral blood smears revealed marked
erythrocyte anisocytosis and poikilocytosis, occasional hypersegmented neutrophils and large platelets. Analysis of bone marrow
aspirates revealed decreased to normal cellularity with adequate iron stores. Serum iron and total iron binding capacity were nor-
mal. Serum biochemistry analyses were within normal limits for age-matched controls.
Intestinal maldigestion and malabsorption were ruled out based on normal GI contrast radiography, normal absorption of starch
and fat and normal serum trypsin-like immunoreactivity. Normal hepatic function was documented by ammonia tolerance and BSP
retention tests.
A urine sample was submitted for metabolic screening. Analysis revealed methylmalonic aciduria, which is a sign of vitamin B 12
deficiency. Two serum samples had vitamin B 12 concentrations of 21 and 36 pg/ml (values for normal dogs 209 to 483 pg/ml).
Results of a test to measure intestinal absorption of an orally administered dose of vitamin B 12 were suboptimal.
Assess the Food and Feeding Method
The puppy was fed a variety of homemade and commercial dog foods free choice, supplemented with an oral liquid hematinic.

Treatment and Feeding Plan
Vitamin B 12 (1 mg) was administered intramuscularly once daily for seven days. A complete and balanced commercial dry growth
dog food was offered free choice.

Reassessment
Within 12 hours of the vitamin B 12 injection, the puppy became bright and alert and developed a voracious appetite. Two weeks
after treatment, the puppy had gained 7 kg; six weeks after treatment the puppy weighed 25 kg. Reticulocytosis occurred five days
after parenteral vitamin B 12 therapy was started. Neutrophil counts increased within 10 days and all hematologic abnormalities
resolved within two months. The dog remained clinically normal when given 1 mg vitamin B 12 intramuscularly every four to five
months.
Subsequent testing of this puppy’s mother documented an inborn error of vitamin B 12 metabolism leading to selective vitamin
B 12 malabsorption. Inherited selective malabsorption of vitamin B 12 has been described in other giant schnauzer puppies and in
a cat.

Bibliography
Fyfe JC, Jezyk PF, Giger U, et al. Inherited selective malabsorption of vitamin B 12 in giant schnauzers. Journal of the American
Animal Hospital Association 1989; 25: 533-539.
Vaden SL, Wood PA, Ledley FD, et al. Cobalamin deficiency associated with methylmalonic acidemia in a cat. Journal of the
American Veterinary Medical Association 1992; 200: 1101-1103.