Hemorrhagic Gastroenteritis (HGE), now often called Acute Hemorrhagic Diarrhea Syndrome (AHDS), is an acute, severe condition in dogs characterized by the sudden onset of profuse bloody diarrhea and vomiting. This disorder progresses rapidly and requires immediate veterinary intervention. Without prompt medical attention, the massive fluid loss can quickly lead to life-threatening complications.
Defining Hemorrhagic Gastroenteritis
HGE involves a sudden, intense inflammation of the gastrointestinal tract lining, particularly the small intestine. This inflammation increases the intestinal wall’s permeability, allowing large amounts of fluid, plasma proteins, and red blood cells to leak into the gut lumen. This rapid fluid loss from the bloodstream results in severe dehydration and a condition known as hemoconcentration. Hemoconcentration is the dramatic thickening of the blood due to the loss of its liquid components, which is the hallmark diagnostic feature of HGE. The proportion of red blood cells in the total blood volume, measured by the Packed Cell Volume (PCV), becomes highly elevated, often rising above 60% (compared to a normal range of 37% to 55%). Although the PCV is high, the total protein level often remains normal or only slightly decreased, which helps distinguish HGE from other causes of severe dehydration.
Identifying the Underlying Causes
The precise etiology of HGE is often classified as idiopathic, meaning the cause remains unknown in many cases. However, research suggests that an overgrowth of the bacterium Clostridium perfringens may play a significant role. This bacterium may produce toxins like NetF that damage the intestinal lining and trigger the syndrome. Small and toy-breed dogs are disproportionately affected by HGE, with Miniature Poodles, Miniature Schnauzers, and Yorkshire Terriers being commonly overrepresented. Potential triggers associated with the onset of HGE include dietary indiscretion (ingesting non-food items or unaccustomed foods). Psychological stressors, anxiety, and hyperactivity have also been suggested as contributing factors in susceptible dogs.
Diagnosis and Clinical Signs
The clinical presentation of HGE is typically acute and dramatic, often beginning with vomiting that precedes the bloody diarrhea. Owners will notice profound lethargy and a characteristic profuse, watery diarrhea that is heavily mixed with blood, often described as having a “raspberry jam” or “strawberry jam” appearance. Affected dogs may also show signs of abdominal pain and a reduced appetite. Diagnosis starts with a physical examination and the patient’s history, but confirmation relies on specific blood work. The Packed Cell Volume (PCV) is measured to confirm hemoconcentration, with a reading often greater than 60% being highly suggestive of HGE. The veterinarian will also perform other diagnostic tests, such as fecal screens and imaging, to rule out serious causes of bloody diarrhea, including Parvovirus infection, intestinal parasites, foreign bodies, or ulcers.
Treatment and Recovery Protocol
Treatment for HGE is aggressive and supportive, aiming to counteract severe dehydration and restore circulatory function. Immediate and continuous intravenous (IV) fluid therapy is the foundation of the treatment plan, often administered at a rapid rate to correct the fluid deficit. Subcutaneous fluids are generally not sufficient to address the massive fluid loss experienced by these patients. Supportive care includes anti-nausea medications, such as maropitant, to control vomiting and improve comfort. Broad-spectrum antibiotics are frequently administered to prevent systemic infection, given the damaged intestinal barrier. During the initial stabilization period, food and water are typically withheld to allow the inflamed gastrointestinal tract to rest. With prompt intervention, the prognosis is generally good; most dogs show significant improvement within 24 to 48 hours and make a full recovery, though hospitalization is mandatory.