Renal Involvement in Rheumatic Diseases - Unraveling Complex Interactions

Introduction

The majority of inflammatory chronic disorders are caused by rheumatoid arthritis. Patients with rheumatic disorders have higher rates of morbidity and death because kidney-related symptoms are frequently present. Primary rheumatic illness care should become more active when individuals with rheumatic disorders exhibit signs or symptoms of renal involvement. Generally speaking, the kind of main rheumatic illness a patient has determines the risk and severity of renal involvement.

The primary reasons for renal involvement in people with rheumatic disorders include the rheumatic disease itself, long-term use of immunosuppressive medications and non-steroidal anti-inflammatory medicines, and comorbidities such as diabetes, hypertension, and cardiovascular problems.

Several investigations have identified the prominent characteristics of renal involvement in most rheumatic illnesses. This article provides an overview of the connections between rheumatic illnesses and kidney disorders and the pathophysiology and clinical characteristics of renal involvement brought on by primary rheumatic diseases.

How Does Rheumatic Disease Affect the Kidneys?

Renal involvement is a risk factor for certain rheumatoid arthritis patients. It is generally one in four, compared to one in five for non-rheumatoid arthritis patients. However, because most people with chronic renal disease and rheumatoid arthritis do not have a kidney biopsy, the kind of kidney disease is not always evident. Numerous renal problems have been discovered in individuals who had biopsies, including disorders affecting the kidneys' microscopic filters, a buildup of immunological compounds inside the kidney, and a protein deposit that results in kidney failure.

There are two primary ways rheumatoid arthritis may raise the risk of renal issues.

1. Inflammation: Medical professionals think renal impairment results from the disease's general inflammatory load. The small blood veins in the kidneys are similarly more vulnerable to damage from inflammation than the heart, which increases the risk of heart disease. The chance of having impaired kidney function increases with the severity of the condition.

2. Medication: Most rheumatoid arthritis drugs do not directly harm the kidneys. However, some may create issues if individuals already have decreased kidney function.

• Non Steroidal Anti Inflammatory Drugs (NSAIDS): For most reasonably healthy individuals, regular dosages of over-the-counter nonsteroidal anti-inflammatory medicines (NSAIDS) like ibuprofen and naproxen do not cause any issues. All NSAIDs, however, decrease the blood flow to the kidneys. For people with decreased renal function, which includes many elderly individuals, this may be harmful.

• Steroids: Prednisone is one corticosteroid that causes fluid retention, which can increase blood pressure. This may worsen renal illness over time.

• Methotrexate: The kidneys are used to get rid of this medication. It can accumulate in the bloodstream and lead to an overdose if the kidneys are not functioning as they should.

• Cyclosporine: Cyclosporine is a potent immunosuppressant that may impair renal function. According to the American College of Rheumatology, around 50 percent of individuals experience moderate renal difficulties while on cyclosporine and may need to adjust their dosage or stop the medicine. After the medication is withdrawn, kidney function normally becomes better.

What Are the Symptoms of Renal Involvement in Rheumatic Diseases?

Kidney illness sometimes does not show symptoms until it is well advanced. Certain symptoms, such as lethargy and a lack of appetite, resemble those of RA. Never hesitate to report any new or worsening symptoms to the doctor.

Advanced kidney disease symptoms include:

• Reduced desire to eat.

• Tiredness.

• Skin that is itchy or has darkened.

• Spasms in the muscles (particularly at night).

• Puffiness surrounds the eyes.

• Breathing difficulties.

• Swollen ankles and feet.

• Difficulty focusing.

• Difficulty falling asleep.

• Urge for frequent urination.

What Are the Risk Factors for Renal Involvement in Rheumatic Diseases?

There are a number of variables that may contribute to rheumatoid arthritis's (RA) renal involvement:

• Diabetes: In general, diabetes is a major risk factor for kidney issues, and in people with rheumatoid arthritis, this risk is increased. Renal problems associated with rheumatoid arthritis are more likely to occur when blood sugar levels are high because they can harm the kidneys over time.

• Family History: A family history of renal illness indicates a possible hereditary susceptibility to kidney issues. Even in the absence of pre-existing kidney problems, this may raise the chance of developing renal difficulties in people with rheumatoid arthritis. When someone has rheumatoid arthritis and a family history of kidney illness, regular monitoring of kidney function using tests such as the estimated glomerular filtration rate (eGFR) and the urine protein-to-creatinine ratio (UPCR) is crucial to spotting any early indications of kidney issues.

• Heart Disease: Risk factors for rheumatoid arthritis and heart disease, such as high blood pressure, cholesterol, and inflammation, are frequently identical. Additionally, heart health may be impacted by some rheumatoid drugs. The prognosis for rheumatoid arthritis might deteriorate if cardiac disease already exists, and vice versa. Efficiently handling both circumstances is necessary for effective disease management.

• Hypertension: Uncontrolled hypertension accelerates the development of renal disease in a number of illnesses, including rheumatoid arthritis, and is a significant risk factor for kidney injury. For people with rheumatoid arthritis, keeping blood pressure within suggested levels by making lifestyle changes and using medication as needed to safeguard renal function and general health is crucial.

• Elevated Cholesterol: High cholesterol can lead to heart disease, which can interact with rheumatoid arthritis and associated renal consequences, even if it is not directly connected to kidney illness.

How to Diagnose the Renal Involvement in Rheumatic Diseases?

The following tests can be done to determine renal involvement in rheumatoid arthritis.

• Urinalysis: This simple test looks for abnormalities in the urine, such as blood, white blood cells, or protein. Generally, a urine dipstick test is done to evaluate proteinuria (protein in urine), hematuria (blood in urine), and pyuria (pus in urine).

• Ratio of Urine Protein to Creatinine (UPCR): This quantitative test calculates the ratio of protein excretion in urine to creatinine, a kidney function indicator.

• Estimated Glomerular Filtration Rate (eGFR) and Serum Creatinine: These tests measure waste products in the blood to evaluate kidney function.

• Blood Tests: Certain antibodies linked to certain rheumatic disorders, such as rheumatoid factor in rheumatoid arthritis, can be tested to determine whether the kidneys are involved.

What Are the Precautionary Measures to Be Taken by Individuals With Rheumatic Disease?

Kidney protection can be achieved in several ways:

• Ensure that rheumatoid arthritis is under control.

• Discuss all medicines with the doctor. A doctor might advise taking some drugs at lower doses if they already have renal issues. In general, NSAIDs are not recommended for those who already have renal issues.

• Take tests regularly. Finding out if kidney function is almost normal is crucial. The drugs one takes, and any additional medical issues they may have may determine how frequently they have blood and urine testing. Consult the physician.

• Regulate cholesterol and blood pressure. Kidney disease is more common in those with high blood pressure and excessive cholesterol.

• Make sure to stay hydrated. A healthy kidney depends heavily on hydration, although many individuals do not get enough water in their diets.

• Restrict the amount of salt in an individual's diet. Consuming excessive amounts of salt can lead to hypertension, which poses a risk to the kidneys.

Conclusion

Kidney damage can result from rheumatic disorders, a broad category of illnesses marked by persistent pain and inflammation in the joints, muscles, and connective tissues. The effects of renal involvement in rheumatic disorders can be reduced by early diagnosis, adequate therapy, and vigilant monitoring. When rheumatologists and nephrologists collaborate, they can create individualized treatment programs that maximize kidney function and enhance patients' general quality of life.