Common Complications Associated with Nephrotic Syndrome
Nephrotic syndrome is a serious kidney disorder characterized by excessive protein loss in the urine, low levels of protein in the blood, high cholesterol, and swelling—particularly in the legs, feet, and around the eyes. While managing the primary symptoms is crucial, it's equally important to recognize and address the potential complications that often accompany this condition. Left unchecked, these secondary issues can significantly impact a patient's quality of life and long-term prognosis.
1. Increased Risk of Infections
Patients with nephrotic syndrome are highly susceptible to infections due to both immune system dysfunction and the treatments used to manage the disease. The chronic loss of proteins, including immunoglobulins, weakens the body's natural defenses. This immunocompromised state makes individuals more vulnerable to bacterial and viral pathogens. Common sites of infection include the respiratory tract (such as pneumonia), urinary tract (UTIs), and gastrointestinal system. Additionally, the use of corticosteroids and immunosuppressive drugs—while effective in reducing kidney inflammation—further suppresses immune activity, increasing infection risk even more.
2. Blood Clots and Embolic Events
Hypercoagulability is a hallmark complication of nephrotic syndrome. Due to the significant loss of proteins like antithrombin III and other natural anticoagulants through urine, the blood becomes more prone to clotting. This imbalance can lead to the formation of thrombi, particularly in the deep veins of the legs (deep vein thrombosis) or within the renal veins (renal vein thrombosis). In severe cases, these clots may dislodge and travel to the lungs, causing a potentially life-threatening pulmonary embolism. Early detection and preventive anticoagulant therapy are essential for at-risk patients.
Why Hypercoagulability Occurs
The liver attempts to compensate for protein loss by increasing the production of various proteins, including clotting factors. This overproduction tips the balance toward clot formation. Combined with reduced levels of protective anticoagulant proteins, the stage is set for vascular complications.
3. Acute Kidney Injury and Chronic Kidney Damage
Despite originating in the kidneys, nephrotic syndrome can lead to further deterioration of renal function. Severe proteinuria can cause tubular obstruction and interstitial inflammation, leading to acute kidney injury (AKI). In some cases, persistent damage may progress to chronic kidney disease or even end-stage renal failure requiring dialysis. Factors such as hypovolemia from fluid loss, use of nephrotoxic medications, or superimposed infections can exacerbate this decline.
Monitoring Kidney Function
Regular assessment of serum creatinine, glomerular filtration rate (GFR), and urine output is vital. Prompt intervention during episodes of AKI can help preserve remaining kidney function and prevent irreversible damage.
4. Metabolic Imbalances: Protein and Lipid Disorders
The massive urinary excretion of albumin triggers a cascade of metabolic adaptations. The liver responds by ramping up the synthesis of proteins and lipoproteins, which leads to elevated cholesterol and triglyceride levels—a condition known as hyperlipidemia. Over time, this increases the risk of cardiovascular diseases such as atherosclerosis.
Hormonal Influence on Metabolism
Treatment with glucocorticoids, while necessary for inducing remission, contributes to metabolic disturbances. These drugs promote muscle protein breakdown, impair glucose tolerance, and stimulate fat deposition, especially in the face, abdomen, and upper back. As a result, patients may develop steroid-induced diabetes, weight gain, and altered body composition.
In summary, nephrotic syndrome extends beyond kidney dysfunction—it triggers a complex array of systemic complications. Effective management requires a proactive, multidisciplinary approach focused not only on controlling proteinuria but also on preventing infections, minimizing thrombotic risks, protecting kidney function, and correcting metabolic abnormalities. With early recognition and tailored interventions, many of these complications can be mitigated, improving overall outcomes for patients worldwide.