Take Home Points: Scleroderma Renal Crisis
What is SRC? – a sudden onset of malignant hypertension and renal failure that occurs in a minority of scleroderma patients.
Pathogenesis – thought to involve small interlobular arteries in the kidneys which develop intimal proliferation and spasm à vasculopathy that reduces renal blood flow à activation or RAAS à hypertension and worsened renal dysfunction
Epidemiology and Onset of Disease
- Occurs in 5-20% of pts with diffuse cutaneous SSc, much less in pts with limited cutaneous SSc
- Occurs early in the disease – almost all in first 5 years of diagnosis of SSc, median time of 7.5 months from first non-Raynaud symptom of SSc!
- Possible risk factors include – use of high dose glucocorticoids, SSc with diffuse skin involvement, ? anti- RNA polymerase III antibody
3 Major Features of SRC
- Abrupt onset mod-severe HTN associated with increased plasma renin activity
- About 10% of pts will NOT have hypertension!
- Acute kidney injury
- Essentially normal urinalysis with only mild proteinuria and few cells or casts
- Other associated features: microangiopathic hemolytic anemia, CHF, pulmonary edema, hypertensive retinopathy and encephalopathy and seizure
Treatment of SRC – untreated, can progress to ESRD in months & death within a year
- ACE INHIBITORS!! Key is to initiate before the onset of permanent renal damage.
- Most evidence with captopril, which is short acting and can be titrated quickly
- Goal is to return pt to baseline BP within 72hrs of starting treatment
- Low dose ACE-I should be continued indefinitely even if BP returns to normal