Abstract
A 3-year-old male Rottweiler presented with the chief complaint of recurrent vomiting, diarrhea, hypothermia, and lethargy. Hypovolemic shock was noted with abnormal electrolytes (Na/K ratio, 27.9) and anemia (hematocrit, 17.3%). Since the hematocrit was 49.2% four days earlier when the primary veterinarian examined the dog, acute anemia was diagnosed. Melena was observed on the next day. The general condition and hydration improved with treatment, and an adrenocorticotropic hormone stimulation test identified hypoadrenocorticism. However, the hematocrit decreased further to 9%, necessitating blood transfusion. The cause of severe acute anemia was thought to be gastrointestinal hemorrhage. It should be noted that hypoadrenocorticism can lead to potentially fatal anemia with gastrointestinal tract bleeding, and blood transfusion may be required.