Primary capillary leakage syndrome (Capillary leak syndrome) is a rare condition that can be a complication of another disease when too much fluid migrates from the blood vessels and into the tissue. Typically, episodes of severe swelling are with fluid retention, especially around muscles in the arms and legs. Symptoms from the lungs, pericardial effusion, kidneys and nervous system may also occur. The symptoms often develop within 1-3 days. The disease occurs as a separate condition (primarily capillary leakage syndrome, Clarkson's disease) or related (secondary) to other conditions, including Systemic connective tissue diseases:, rhabdomyolysis and serious infections (sepsis).
In the disease mechanism, fluid from the blood (plasma) penetrates through the blood vessel walls and into the connective tissue. This causes swelling with fluid accumulation. The condition can occur with a severe course of Systemic connective tissue diseases: that Myositis (including at dermatomyositis in children), blood poisoning (Sepsis), Macrophage activation syndrome (MAS), Poisoning, Snakebite, Cancer with more.
Primary capillary leakage syndrome begins with fatigue and dizziness. Then a drop in blood pressure and a fast pulse are seen as an expression of incipient shock. Low blood pressure reduces kidney function so that symptoms of acute kidney failure can occur in severe cases. Fluid and high levels of protein in the tissue cause pronounced swelling which may also include the lungs and heart sac. Swelling in muscles can be too high pressure in the legs or arms, so-called "compartment syndrome" which puts pressure on blood circulation and nerves. Later in the course, the condition improves, swelling is reduced spontaneously and blood pressure is stabilized. However, life-threatening water on the lungs (pulmonary edema) can occur during this phase.
Medical history should cover the prior risk of poisoning, snakebite, injury, congestion, infection or serious rheumatic disease. Current symptoms (see above) are recorded.
Clinical swelling (edema) and low level of protein in the bloodstream are detected. Other manifestations are acute kidney damage, swelling of the lungs and heart sac, rhabdomyolysis and compartment syndrome in the legs or arms.
Similar conditions / differential diagnoses
- The condition can easily be confused with sepsis, angioedema or anaphylactic shock.
- Allergic reaction
- DRESS syndrome (severe drug reaction)
- Eosinophilic myositis
- Hypokomplementary vasculitis / urcticular vasculitis
- Lipedema (fat accumulation)
- Kidney failure (Acute)
- Early systemic sclerosis (diffuse form)
Capillary leakage syndrome should be treated in a hospital. Proper fluid supply (0.9% NaCl or other electrolyte solutions) is an important part of the treatment. When blood pressure is stabilized, it is appropriate to give diuretics (diuretics) to prevent water in the lungs (pulmonary edema) (Siddal E, 2017). When capillary leak syndrome is caused by systemic connective tissue diseases, corticosteroids have been shown to be useful in addition to fluid therapy. Capillary leakage syndrome after bone marrow transplantation (engraftment syndrome) responds to treatment with steroids (Spitzer TR, 2001). Intravenous immunoglobulin (IVIG) may also be effective and is recommended early in the course of anyone with an unknown cause of capillary leakage syndrome.