From the Guidelines
Splenic dysfunction in patients with Nephrotic Syndrome (NS) is primarily caused by the loss of immunoglobulins, hypoalbuminemia, protein malnutrition, and the use of immunosuppressive medications, which collectively impair the spleen's ability to clear bacteria and increase the risk of infections. The loss of immunoglobulins, particularly IgG, through damaged glomeruli leads to hypogammaglobulinemia, impairing opsonization and bacterial clearance by the spleen 1. Additionally, hypoalbuminemia causes reduced oncotic pressure, resulting in edema that can affect splenic tissue and compromise its function. Key factors contributing to splenic dysfunction include:
- Loss of immunoglobulins through damaged glomeruli
- Hypoalbuminemia causing reduced oncotic pressure and edema
- Protein malnutrition from urinary protein loss weakening immune responses
- Use of immunosuppressive medications to treat the underlying kidney disease
- Alterations in complement components, particularly reduced levels of factors B and D
- Chronic inflammation associated with the syndrome leading to splenic fibrosis over time These factors collectively contribute to an increased susceptibility to infections, especially from encapsulated bacteria, making appropriate vaccination and prompt treatment of infections crucial in these patients 1.
From the Research
Causes of Splenic Dysfunction in Nephrotic Syndrome (NS)
The causes of splenic dysfunction in patients with Nephrotic Syndrome (NS) can be related to the hypercoagulable state associated with the disease. Some of the key factors that contribute to this state include:
- Urinary loss of clotting inhibitors, zymogens, and plasminogen 2
- Increased hepatic synthesis of fibrinogen and lipoproteins 2
- Hemoconcentration due to fluid loss 2
- Abnormalities in platelet activation and an imbalance between anticoagulation/antithrombosis and procoagulant/prothrombotic mechanisms 3
- Decrease in the levels of coagulation inhibitors (antithromycin III, protein S) and increase in alpha 2-antiplasmin activity 4
- Exaggerated platelet adhesiveness and aggregation 4
Hypercoagulable State and Thromboembolic Complications
The hypercoagulable state in NS can lead to thromboembolic complications, including:
- Renal vein thrombosis 5, 4
- Portal vein thrombosis 2
- Pulmonary embolism 6, 3
- Arterial thromboses 4 These complications can be caused by the increased incidence of thrombotic events in NS, which may be due to the hypercoagulable state distinguished by an increase in coagulation factors (V, VIII, X and fibrinogen) 4.
Risk Factors for Thrombosis
Some of the risk factors for thrombosis in NS include: