Kidney Involvement in Kawasaki Disease

Introduction

Kawasaki disease (KD) can cause damage to several organs, including the kidneys and the urinary tract. Pyuria, prerenal acute kidney injury (AKI), renal AKI due to tubulointerstitial nephritis (TIN), hemolytic uremic syndrome (HUS), immune-complex mediated nephropathy, renal AKI linked to either shock syndrome from Kawasaki disease, nephrotic syndrome (NS), acute nephritic syndrome (ANS), abnormalities in the renal tubules, abnormalities in ultrasound investigations, and renal artery lesions (aneurysms and stenosis) are among these disorders. The exact etiology of the kidney involvement is still uncertain. Still, it is suggested that renal vasculitis, immune-complex-mediated kidney injuries, or abnormalities in T-cell immune regulation have been suggested as potential causes for developing kidney and urinary tract injuries in Kawasaki disease.

What Is Kawasaki Disease?

Kawasaki disease is characterized by enlargement, or inflammation, of the walls of the tiny to medium-sized arteries that provide blood to all body parts. Children with Kawasaki illness typically have cardiac artery problems. The heart receives oxygen-rich blood from those arteries. Another name for Kawasaki disease is mucocutaneous lymph node syndrome.

This is because it also inflames the mucous membranes in the mouth, nose, eyes, and throat and the glands known as lymph nodes. Children with Kawasaki illness may experience red eyes and tongues, swollen hands and feet with peeling skin, and a high fever. However, Kawasaki illness is frequently curable. Most kids who receive therapy early on recover and do not experience any long-term issues.

What Are the Kidney Disorders Caused Due to Kawasaki Disease?

Kawasaki disease causes damage to several organs, including the kidneys. It is necessary to understand the different disorders or illnesses caused by disease to prevent further damage and have a proper diagnosis for disease management. The following are the common disorders in the kidney caused by Kawasaki disease:

• Acute Kidney Injury: Acute kidney injury is sometimes referred to as acute renal failure (ARF). Kawasaki disease is characterized by inflammation of small blood vessels, including those supplying the kidneys. This leads to potential damage to the kidneys.

• Based on the cause, AKI is typically classified into three broad pathophysiologic categories:

  • Prerenal AKI: It is characterized by decreased kidney perfusion without kidney parenchymal damage. Due to decreased blood volume or compromised heart function, the widespread inflammation may cause renal hypoperfusion, a reduction in blood flow to the kidneys. Reduced filtration and consequent renal disease may arise from this.

  • Renal AKI: It is caused by injuries to the renal parenchyma. Renal AKI can occasionally result from direct renal tissue injury caused by the inflammatory response associated with Kawasaki illness. Kidney function may be compromised by immune-mediated inflammation of blood arteries that spreads to the kidney's tissues, resulting in acute tubular necrosis (ATN), glomerulonephritis, or interstitial nephritis.

  • Postrenal AKI: It is caused by acute obstruction of the urinary tract. Even though it is less frequent, severe inflammation of the vasculature around the kidneys might cause blockage in the ureters or urinary system, which can result in postrenal AKI. Kidney function may be impacted by this blockage, which might prevent urine from flowing normally.

  • Both prerenal and renal AKI have been seen in Kawasaki disease patients.

• TubuloInterstitial Nephritis: Tubulointerstitial nephritis can result from inflammation linked to Kawasaki illness spreading to the interstitial tissue of the kidney. This disorder disrupts the kidney tubules' gaps, which may compromise renal function and cause irregularities in urine production.

• Hemolytic Uremic Syndrome: Thrombocytopenia, nonimmune hemolytic anemia, and renal dysfunction are the hallmarks of hemolytic uremic syndrome. One pathogenic feature shared by all kinds of HUS is microvascular injury with endothelial cell destruction. The main cause of hemolytic microvascular damage is genetic, infection-induced, and medication-induced HUS.

• Immune Complex Mediated Nephropathy: The term "immune complex-mediated nephropathy" describes kidney disease brought on by an immune complex buildup within the kidneys. Antibodies attach to antigens to produce these complexes, which can cause inflammation and kidney damage. This response can be brought on by infections or lupus, which can impair kidney function and occasionally result in glomerulonephritis.

• Nephrotic Syndrome: Nephrotic syndrome is a group of symptoms rather than a single illness that characterizes kidney disorders. It is characterized by elevated urine protein levels, low blood protein levels, elevated cholesterol, and swelling (edema), particularly in the belly, feet, and eyes. Numerous renal disorders that harm the kidneys' filtering units, or glomeruli, can result in this condition. Among the common causes are membranous nephropathy and focal segmental glomerulosclerosis.

What Are the Treatment Options for Kidney Involvement in Kawasaki Disease?

Treating Kidney problems related to Kawasaki disease involves a multimodal strategy that emphasizes sustaining renal function and treating the underlying ailment. The following are the commonly employed treatment options for managing kidney problems in Kawasaki disease.

• IVIG Therapy (Intravenous Immunoglobulin): High doses of IVIG are essential for treating Kawasaki illness. It seeks to lessen the risk of coronary artery issues and aid in reducing inflammation. Although IVIG focuses mostly on cardiovascular issues, renal involvement may indirectly benefit from managing systemic inflammation.

• Anti-Inflammatory Medication: Pain and inflammation can be controlled using nonsteroidal anti-inflammatory medications (NSAIDs).

• Diuretics: In situations of edema or fluid overload, these drugs can aid in the body's removal of extra fluid.

• Antibiotics: Antibiotics may be required if a bacterial infection is a factor in kidney damage.

• Dialysis: Temporary dialysis may be required in severe cases of acute kidney injury (AKI) to eliminate waste products and preserve electrolyte balance since the kidneys are unable to function normally.

• Nutritional Support: Sustaining healing and recuperation requires eating a balanced diet with enough calories and protein.

What Is the Prognosis of Kidney Involvement in Kawasaki Disease?

With timely and effective treatment, the majority of kids with kidney involvement in Kawasaki disease make a full recovery. To identify and treat any problems, long-term follow-up and routine blood pressure and renal function testing are necessary.

Conclusion

Kidney involvement in Kawasaki disease is a common phenomenon. Even though the etiology is uncertain. It is crucial to get an early diagnosis using imaging and laboratory investigations. The kind and extent of kidney damage determine the course of treatment. Most kids' healing is satisfactory, but regular monitoring is essential.