Recognizing uterine torsion as a differential diagnosis in pregnant cats with severe anemia to provide appropriate and timely care in the absence of a definitive presurgical diagnosis.

A pregnant female domestic longhair cat ~8 mo of age was referred to the Western College of Veterinary Medicine (Saskatoon, Saskatchewan) for a diagnostic evaluation of severe anemia (PCV: 10.8%) after a 2-day period of lethargy. A CBC, serum biochemistry profile, FeLV/FIV testing, and abdominal radiographs were completed and did not determine a cause for the anemia. Abdominal ultrasonography identified 1 viable and 6 nonviable and fetuses, anechoic fluid in the uterus, and a mild volume of peritoneal effusion. A whole-blood transfusion and C-section with ovariohysterectomy were performed even though a definitive presurgical diagnosis for the anemia had not yet been established. Exploratory surgery revealed a left uterine horn torsion with a necrotic base, severe congestion, and 7 nonviable fetuses. Following surgery, the queen made a full clinical recovery. Key clinical message: Uterine torsion can be easily overlooked as a cause of severe anemia due to the relative infrequency of this condition in cats and the low sensitivity of ultrasonography to provide a definitive presurgical diagnosis. Client communication must emphasize the need for a prompt surgical intervention to establish the diagnosis and to save the cat, despite poor rates of neonatal survival. Once the animal is stabilized after surgery, further diagnostic tests and procedures are indicated if the cause of anemia has not yet been identified.