What is Scleroderma and Renal Crisis?
Scleroderma renal crisis is a very serious complication of a disease called scleroderma. It usually starts suddenly with extremely high blood pressure and quick worsening of kidney function. This can also bring on conditions like hypertensive encephalopathy, which is brain damage caused by high blood pressure; congestive heart failure, a condition where the heart can’t pump enough blood to the body; and microangiopathic hemolytic anemia, a rare condition where red blood cells are destroyed and removed from your bloodstream before their normal lifespan is over.
What Causes Scleroderma and Renal Crisis?
Scleroderma renal crisis, a dangerous kidney condition, happens more often in people with a type of scleroderma called ‘diffuse scleroderma’ (10% to 25% of cases), rather than in those with a limited version of the disease (only 1% to 2% cases). Scleroderma is a disease that causes hardening and tightening of the skin and other tissues.
This kidney condition typically develops early in the course of scleroderma, with up to 75% of cases happening within the first four years after being diagnosed with scleroderma. On average, people experience this kidney problem about 8 months after their scleroderma diagnosis. Sometimes, this kidney condition can even be the first sign that a person has scleroderma.
Certain factors can help predict who might develop scleroderma renal crisis. These include having diffuse scleroderma that progresses rapidly, presence of specific antibodies in the blood called anti-RNA polymerase III antibodies, taking corticosteroid therapy with doses larger than 15 mg per day, having a condition called ‘tendon friction rubs’, newly developed anemia (low red blood cell count), inflammation of the heart’s lining (pericarditis), and heart failure.
Risk Factors and Frequency for Scleroderma and Renal Crisis
Scleroderma renal crisis, a complication of scleroderma disease, used to occur in nearly 20% of patients according to past records. However, this appears to be declining, with current data indicating it happens in about 5 to 10% of scleroderma patients. Earlier research suggested that African-American individuals and males were more likely to develop this condition, but recent studies do not confirm this. The prevalence of this complication also varies by country. It has been observed that more patients show symptoms during the winter and fall months.
Signs and Symptoms of Scleroderma and Renal Crisis
Scleroderma renal crisis is a serious condition related to diffuse scleroderma. People who experience this typically suffer from sudden extreme high blood pressure along with reduced or completely stopped urine production, leading to acute kidney failure. It’s common for these individuals to have protein and blood in their urine. Additionally, they may have hypertensive retinopathy (a condition affecting the eyes due to high blood pressure), experience changes in mental status including confusion and altered vision, and could develop congestive heart failure. Blood disorders like low platelet count and a specific type of anemia (microangiopathic hemolytic anemia) might also present.
- Sudden high blood pressure
- Reduced or stopped urine production
- Protein and blood in urine
- Eye problems due to high blood pressure
- Confusion and vision changes
- Congestive heart failure
- Low blood platelet count
- Type of anemia called microangiopathic hemolytic anemia
Testing for Scleroderma and Renal Crisis
A kidney biopsy may not be required in typical cases, but it could be helpful for patients with unusual symptoms. For instance, a patient with a condition called scleroderma might need a kidney biopsy if they show higher levels of serum creatinine (a waste product that the kidneys filter out) in their blood tests, normal blood pressure, and have active urine sediments (particles in the urine) or high level of protein in urine, a condition called nephrotic range proteinuria.
Treatment Options for Scleroderma and Renal Crisis
The RAAS (Renin-Angiotensin-Aldosterone System) plays a significant role in triggering scleroderma renal crisis, a dangerous kidney complication associated with a disease called scleroderma. The use of certain medication known as angiotensin-converting enzyme inhibitors (or ACEIs, which help control blood pressure) has significantly decreased the death rate associated with this kidney complication, reducing the mortality rate from 85% to around 25%.
Therefore, prompt treatment usually involves hospitalization and starting ACEI medication to lower blood pressure quickly. It commonly starts with a short-acting ACEI such as captopril. The aim is to reduce systolic blood pressure (the top number in a blood pressure reading) by about 20mm Hg in 24 hours, and to reach a target blood pressure of 120/70mm Hg within 72 hours. Some care is taken to ensure that blood pressure doesn’t get too low during this intense treatment.
If blood pressure refuses to come down even with the maximum doses of ACEI, another type of medication known as a dihydropyridine calcium channel blocker may be added to the course of the therapy. Diuretics, which are medications that help your body to get rid of excess water and salt, should be avoided as they can trigger the RAAS.
It’s important to note that ACEI therapy can possibly diminish kidney function to a point where dialysis becomes necessary. However, treatment should still be continued since approximately 50% of patients may regain enough kidney function over a period of 3 to 18 months to discontinue dialysis.
While ACEIs have improved patient outcomes, they don’t prevent scleroderma renal crisis and using them prematurely might increase the risk of death due to delayed diagnosis.
There are other alternatives in the management of scleroderma renal crisis such as endothelin receptor antagonists and a vasodilating prostaglandin (prostacyclin), which help control blood pressure and improve blood flow to the kidneys.
It’s also important to note that recovery from a scleroderma renal crisis can take up to 24 months, so decisions about kidney transplantation shouldn’t be made until then.
Kidney transplantation can improve survival rates compared to long-term dialysis. However, patients with scleroderma have lower graft (organ transplantation) survival rates and overall survival rates due to the progression of the disease in other body organs. Recurrence of scleroderma renal crisis in the transplanted kidney is relatively rare (5%), but can happen, particularly in patients who had a severe form of the disease before transplantation.
What else can Scleroderma and Renal Crisis be?
: When determining the cause of renal crisis in someone with scleroderma, doctors often need to consider several other conditions that could cause similar symptoms. These conditions could include:
- Thrombotic microangiopathy (a rare blood disorder)
- Malignant hypertension (severely high blood pressure)
- Rapidly progressive glomerulonephritis (rapid loss of kidney function)
Both malignant hypertension and scleroderma renal crisis typically result in significantly increased blood pressure, making these two conditions hard to differentiate if the patient’s medical history doesn’t clearly indicate long-standing, uncontrolled hypertension.
Moreover, with rapidly progressive glomerulonephritis, milder elevations in blood pressure are observed. Patients may have blood or protein in the urine and a greater degree of protein loss in their urine compared to scleroderma renal crisis. Where identification is uncertain, blood tests for various causes of rapidly progressive glomerulonephritis can help.
In some cases, where renal crisis is the first sign of scleroderma, kidney biopsy may be the only effective way to finalize the diagnosis.
What to expect with Scleroderma and Renal Crisis
ACE inhibitors, a type of medication, have greatly improved the outcomes for patients suffering from scleroderma renal crisis, a severe kidney condition associated with scleroderma. Prior to the use of these drugs, only 10% of patients survived one year past diagnosis. Now, with the help of ACE inhibitors, 85% can expect to live till at least one year, and 65% can have the hope of reaching five years.
About two-thirds of individuals with scleroderma renal crisis might need renal replacement therapy, which is a medical term for kidney treatments like dialysis. Of these, about half will recover enough kidney function to stop the dialysis treatments. However, whether a patient does or doesn’t require dialysis can significantly affect their survival rate – those requiring dialysis generally have a higher mortality rate than those who do not. But, of those who require dialysis, patients who manage to improve their kidney function enough to stop treatments fare better than those who continue to require them.
There are several factors associated with a poorer outcome in scleroderma renal crisis that include:
- Having a high level of creatinine – a waste product – in their blood (more than 3 mg/dl) at diagnosis.
- Delay in starting treatment for high blood pressure.
- Not having well-controlled blood pressure.
- Being older in age.
- Being male.
- Having heart failure.
- Experiencing scleroderma renal crisis without high blood pressure.
Finding certain abnormalities in a kidney biopsy like the death of artery cells, severe lack of blood supply to the kidney’s filters, or severe kidney tissue damage and scarring can also indicate a poorer outcome.