At a glance
What is disseminated intravascular coagulation?
Disseminated intravascular coagulation (DIC) is a rare, life-threatening condition in which systemic activation of coagulation occurs, resulting in the formation of blood clots (microvascular thrombosis) throughout the small blood vessels. Clotting is a vital response that serves to protect the blood from being lost from damaged blood vessels; however, DIC causes blood clotting to become overactive leading to problems.
Coagulation is a process in which the blood changes from liquid to a solid/gel, which occurs when damage occurs to blood vessel walls. Usually, when the blood vessel wall is damaged, platelets, a type of blood cell, clump together and bind to the site of the damaged vessel and proteins (coagulation factors) respond to form fibrin, which are thin, long strands, that entangle platelets to form a mesh. Together, this forms a plug over the damaged area, preventing blood loss.
DIC is a secondary disorder to several underlying causes; the primary condition triggers the coagulation process.
Known causes of DIC include:
- Inflammatory conditions
- Immune-mediated hemolytic anemia
- Hepatic lipidosis
- Infections (viral or bacterial)
- Liver disease
Clinical signs may vary depending on the underlying condition, and if the DIC is acute or chronic.
DIC occurs in four phases:
- The underlying disease triggers blood clots to develop in the small blood vessels.
- Blood clots in the vessels reduce or inhibit blood flow through microcirculation.
- Eventually, the increase in clotting uses up platelets and clotting factors, which in turn leads to excessive bleeding.
- As blood flow to organs becomes compromised, other clinical features develop such as kidney or liver failure.
DIC can be acute (sudden onset) or chronic (slow and progressive). Symptoms are more severe and life-threatening in cats with acute DIC and bleeding is typically present. Chronic DIC symptoms are generally much milder, and bleeding is usually not observed.
- Bruising under the skin
- Spots under the skin (petechiae)
- Bleeding from the nose and gums
- Blood in the urine and/or black, tarry stools, vomiting blood.
MODS (multiple organ dysfunctions) or MOFS (multiple organ failure syndromes):
- Kidney failure – Reduced urine production, vomiting.
- Liver failure – Neurological disorders, jaundice (yellow gums), convulsions and, coma.
- Heart failure – Difficulty breathing and increased heart rate, cardiac arrhythmias.
The veterinarian will perform a physical examination and obtain a medical history from you. There is no one single test that can diagnose DIC and diagnosis is based on presenting symptoms as well as a range of laboratory findings.
- Complete blood count – A blood test to evaluate for signs of infection (increased white blood cell count), regenerative or nonregenerative anemia, decreased packed cell volume, low platelet count (thrombocytopenia), an excess of hemoglobin in the blood plasma (hemoglobinemia), fragmented red blood cells (schistocytes).
- Biochemical profile – A test of the clear portion of the blood which may reveal hyperbilirubinemia (high bilirubin levels in the blood), azotemia (elevated BUN and creatinine levels) and increased liver enzymes.
- Blood smear examination – To evaluate for schistocytes (a fragmented part of a red blood cell), anemia, and neutrophilia (a high number of a type of white blood cell known as a neutrophil).
- Blood clotting tests – PT (prothrombin time) or APTT (activated partial thromboplastin time) to determine how fast it takes for the blood to clot.
- Urinalysis – A test of the cat’s urine to check for infection and signs of kidney failure, hemoglobinuria (blood in the urine) along with bilirubinuria (bilirubin in the urine) may be present.
- Serum fibrinogen concentrations – May reveal abnormally low levels.
- Ultrasound – To evaluate the organs, check for tumours and signs of internal bleeding.
- X-rays – Chest, and abdomen to check for tumours.
The goal is to treat the underlying cause as well as provide supportive care which may include transfusion of plates (fresh or frozen plasma) for cats whose plates have been depleted due to bleeding, intravenous fluids to maintain adequate blood flow to the organs. Heparin is an anticoagulant that may be used carefully to reduce coagulation activation, and blood transfusion for anemic patients.
The prognosis for cats with DIC is poor, especially for cats suffering an acute episode.