A 56-year-old woman is brought to the hospital due to altered mental status after being found at home in a state of confusion by her husband. He reports that the patient has had headaches and intermittent vision changes for the past week. She has no other medical history. Temperature is 36.6 C (98 F), blood pressure is 220/115 mm Hg (previously 100/66 mm Hg), and pulse is 90/min. Oxygen saturation is 99% on room air. On examination, the patient is lethargic. Flexion of the neck does not elicit pain. The skin on the hands is shiny and thickened with multiple telangiectasias. The lungs are clear, and there is 1+ lower extremity edema to the shins. A noncontrast head CT scan is unremarkable. Laboratory results are as follows:
| Leukocytes | 8,000/mm3 | |
| Potassium | 4.8 mEq/L | |
| Bicarbonate | 18 mEq/L | |
| Blood urea nitrogen | 20 mg/dL | |
| Creatinine | 3.4 mg/dL | (previously 0.8 mg/dL) |
Urinalysis demonstrates 1+ proteinuria without bacteria or casts. Which of the following is the best next step in management of this patient?
Systemic sclerosis | |
Pathogenesis |
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Clinical features |
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Autoantibodies |
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Complications |
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AKI = acute kidney injury; HTN = hypertension; MAHA = microangiopathic hemolytic anemia; SSc = systemic sclerosis. | |
This woman with shiny, thickened skin and multiple telangiectasias likely has systemic sclerosis (SS) (ie, scleroderma), which is characterized by widespread fibrosis of multiple organ systems. Other common manifestations include swollen digits, ulcerations at the digital tips, and Raynaud syndrome. In association with severe hypertension and acute renal failure, this presentation suggests scleroderma renal crisis (SRC).
SRC is a life-threatening complication of systemic sclerosis that may be the initial manifestation of the disease. Renal vascular injury (due in part to collagen deposition) leads to renal ischemia, which results in activation of the renin-angiotensin-aldosterone system (RAAS). This raises blood pressure and further damages the renal vasculature, causing a vicious cycle of worsening hypertension and renal dysfunction (eg, elevated creatinine, edema). Hypertensive emergency with end-organ dysfunction (eg, encephalopathy, retinal hemorrhage) is common. Thrombocytopenia and microangiopathic hemolytic anemia can be seen. Urinalysis is usually normal but may show mild proteinuria, as in this patient; casts are unexpected.
The mainstay of therapy for SRC includes ACE inhibitors, which reduce RAAS activity and improve renal function and blood pressure. Short-acting ACE inhibitors (typically captopril) are used because they can be rapidly uptitrated. An elevated serum creatinine level is not a contraindication for ACE inhibitors in this population, and slight elevations in creatinine are common during drug initiation.
(Choice B) Beta blockers (eg, esmolol) are usually avoided in patients with SS due to the increased risk of vasospasm (eg, worsening Raynaud phenomenon).
(Choice C) Hemodialysis may be required in some patients with SRC; however, this patient has no urgent indications (eg, hyperkalemia, volume overload with respiratory impairment). ACE inhibitors improve renal function and would likely prevent the need for dialysis.
(Choice D) Glucocorticoids (ie, methylprednisolone) can cause salt and water retention and lead to hypertension; they are a major risk factor for the development of SRC and should be avoided in patients with SS.
(Choice E) Transdermal clonidine can serve as an antihypertensive but is typically slower acting and cannot be rapidly uptitrated. In addition, it would not treat the underlying RAAS hyperactivity.
Educational objective:
Scleroderma renal crisis is characterized by the acute onset of hypertension and acute kidney injury in patients with systemic sclerosis. The mainstay of therapy is ACE inhibitors (typically captopril), which reduce renin-angiotensin-aldosterone system hyperactivity, improve renal function, and normalize blood pressure.