Definition

Acute hypertensive renal crisis ("renal crisis") / scleroderma renal crisis is a serious complication that occurs in 5-10% with the diffuse form of Systemic sclerosis  and less frequently (2%) in the limited form. Kidney crisis most often occurs during the first two to three years after the onset of the disease. The kidneys lose function quickly and blood pressure rises.

• Occurrence of Anti-RNA polymerase III antibody (10-60%) in blood sample is a determining factor
  • RNA polymerase III antibody occurs in 10-60% who experience scleroderma renal crisis
  • Renal crisis usually develops within the first few years of the disease course
• Corticosteroids (Prednisolone, SoluMedrol) are unfavorable and may trigger a new crisis in systemic sclerosis
• Fast onset treatment with ACE inhibitors or AT inhibitors is important, but preventive ACE inhibitor therapy does not help.

Symptoms

• New headache
• Nausea
• Visual disturbances
• Epileptic cramps
• Renal function falls rapidly
  • Renal function is measured by creatinine or GFR in serum (blood sample)
• Blood pressure increases sharply (more than 150 / 90mmHg, often much higher)
• Normotensive scleroderma kidney crisis occurs (10%)
  • Creatinine rises above 50% from baseline values
  • New proteinuria
  • New Hematuria
  • Platelets under 100.000
• Kidney crisis can quickly cause lasting kidney damage, and high blood pressure damages the brain (encephalopathy), eyes (retinopathy) and the heart (failure)

  

  Kidney crisis, tissue sample: Micronephro-angiopathy in scleroderma renal crisis Affiliation: Batal I, 2010. Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, USA. Open

Examinations

• Blood pressure measurements every hour until normalization (monitoring department)
• Blood tests (renal function)
  • Creatinine (rising) and GFR (falling), LD (rising), Haptoglobin (falling: exclude) Hemolytic anemia), Platelets (falls), reticulocytes (rises), blood smears (Schistocytter over 1%)
  • RNA polymerase III is examined in a blood sample (if unknown status) by agreement with the Immunological Lab, Oslo University Hospital
  • ADAMTS13 (Willebrand factor-cleaving protease activity in plasma) is normal, unlike low values ​​at Thrombotic thrombocytopenic purpura, TTP/ Thrombotic microangiopathy which is a differential diagnosis
    • Sending sample to the Department of Biochemistry, St Olavs Hospital
• Urine (proteinuria and hematuria may be present). Urine production (falling) must be measured
• Collaboration with nephrologist
• Kidney biopsy can be done when blood pressure is normalized
• Eye doctor examination / ophthalmoscopy to assess retinopathy
• ECG, troponins and echocardiography if cardiac symptoms
• Telemetry

Diagnosis

• Known systemic sclerosis, most often diffuse form with short disease duration
• Declining renal function
  • 50% increase in creatinine in the blood or 20% over the upper reference range
• Proteins in the urine (> 2+ on stick)
• Blood in the urine (> 2+ or 10 reds per field of view)
• Platelets in the blood are below 100.000

Incorrect diagnosis (Similar conditions, Differential diagnoses)

• Anti - GBM is taken for differential diagnostic reasons (Goodpastures disease)
• Catastrophic Antiphospholipid Syndrome (Lupus Anticoagulant, Cardiolipin, Beta-2 GP)
• TTP-HUS, aHUS

Treatment

Treatment is extremely important for the prognosis and early treatment is essential.

• Treatment is often started at an intensive care unit that monitors the course of the disease

Medication

• ACE inhibits captopril (Capoten®) first choice
  • The starting dose is 6,25 mg - 12,5 mg which is gradually increased to 12,5 -25mg every 4 to 8 hours if blood pressure dictates
  • Maximum doses are 300-450mg / day
  • The systolic blood pressure should decrease by approx. 20 mmHg per day, diastolic blood pressure reduction by 10 mmHg per day until normalization
  • One strives to reach the patient's baseline blood pressure within 3 days
  • Also, normotensive patients (with other symptoms of kidney crisis) should be treated, but then with lower doses, such as captopril 6,25-12,5mg / day
  • Increasing creatinine in blood samples is common due to the disease, but also as a side effect to ACE inhibitor
  • If cough or other side effects occur from ACE inhibitors, may Angiotensin blockers (AT-II inhibitors) be alternatives. Similarly, due to lack of effect of ACE inhibits during 2 day

If a lack of treatment response can be attempted:

• AT II blocks
• Calcium channel blockers

Prognosis

The prognosis is best when treatment begins early, but differs from person to person. Normalization of renal function in 10-40% of cases. Transient dialysis is required in approx. 50%. Approximately 20% need sustained dialysis / kidney transplantation.

• Relapse of scleroderma renal crisis is very uncommon

Literature

• Prabhakar N, 2019
• Mouthon L, 2014

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