Capillary Leak Syndrome
Capillary leak syndrome occurs when the liquid part of your blood, known as plasma, leaks out of tiny blood vessels called capillaries. This fluid then seeps into muscles, tissues, organs, and body cavities. Episodes of capillary leak syndrome can vary in frequency, happening multiple times a year or just once. Without treatment, it can lead to a rapid drop in blood pressure, resulting in organ failure and potentially death.
While there is no cure for capillary leak syndrome, prompt medical treatment is crucial to manage symptoms. Regular use of medications or infusions may help prevent future episodes.
Types of Capillary Leak Syndrome
There are two primary types of capillary leak syndrome:
Systemic Capillary Leak Syndrome (Primary Capillary Leak Syndrome or Clarkson’s Disease): This type involves recurrent episodes, typically occurring in otherwise healthy individuals.
Secondary Capillary Leak Syndrome: This type is triggered by an underlying disease, condition, or medication and usually involves a single episode.
Who Is at Risk?
Systemic Capillary Leak Syndrome
This rare disorder affects fewer than 500 individuals worldwide and is more common in middle-aged adults. It is exceptionally rare in children, but it may be underdiagnosed.
Secondary Capillary Leak Syndrome
This can affect individuals of any age and is often caused by infections, diseases, or certain medications.
How Does a Capillary Leak Syndrome Episode Affect the Body?
An episode of capillary leak syndrome unfolds in three phases:
Prodromal Phase: Occurring one to two days before an attack, symptoms may include fatigue, thirst, and sudden weight gain.
Leak or Resuscitation Phase: During the attack, fluids and albumin (a protein in blood plasma) leak from capillaries into tissues, leading to reduced blood flow, lowered blood pressure, and the accumulation of red blood cells. This results in hypovolemia, a decrease in blood volume.
Post-Leak Phase or Recruitment Phase: After the episode, capillaries reabsorb fluids and albumin from tissues, causing fluid overload, increased urine output (polyuria), and fluid accumulation in the lungs (pulmonary edema).
Causes of Capillary Leak Syndrome
Systemic Capillary Leak Syndrome
The exact cause remains unknown. Researchers suspect that an immune system response to an illness or infection might trigger the condition.
Secondary Capillary Leak Syndrome
This is most commonly caused by sepsis but can also result from various conditions and medications, including autoimmune diseases, differentiation syndrome, engraftment syndrome, and more.
Symptoms
Before an Episode
Symptoms typically appear one to two days before an attack and may include:
- Abdominal or muscle pain
- Fatigue
- Headache
- Increased thirst
- Irritability
- Nausea
- Sudden weight gain
During an Episode
During the leak or resuscitation phase, symptoms can vary but often include:
- Body swelling
- Diarrhea
- Low blood pressure
- Thickened blood
- Other abnormal blood parameters
Diagnosis
Healthcare providers diagnose capillary leak syndrome through a detailed health history, physical examination, and blood pressure assessment. Blood tests are used to identify specific abnormalities related to the syndrome, such as increased hematocrit and hemoglobin levels and low blood protein levels (hypoalbuminemia).
Treatment
While there is no cure, treatment focuses on managing symptoms and preventing complications. This may include:
- Glucocorticoids
- Intravenous fluids to maintain blood flow to vital organs
- Diuretics in the post-leak phase to reduce fluid buildup
Prevention
Preventing systemic capillary leak syndrome is not possible, but regular use of medications or infusions may help prevent future episodes and reduce their severity. Preventive treatments include:
- Monthly intravenous immune globulin (IVIG) infusions
- Oral medications
Outlook
With preventive treatments, systemic capillary leak syndrome can usually be managed. Early diagnosis and fewer complications generally result in better outcomes. Serious complications may include:
- Compartment syndrome
- Cardiac and pulmonary issues
- Kidney and nerve damage
- Other severe conditions
When to Consult a Healthcare Provider
If you suspect the onset of a capillary leak syndrome episode, seek immediate medical attention to manage symptoms and improve your comfort.
