This patient's elevated blood pressure is clearly an acute change based on her prior blood pressure measurements. The most likely diagnosis in this case is scleroderma renal crisis. Underlying scleroderma should be considered in this patient given her history of Raynaud phenomenon and GERD. Scleroderma (systemic sclerosis) is characterized by the abnormal deposition of collagen in multiple organ systems. The majority of the patients have underlying renal involvement, but overt symptoms of scleroderma renal disease are seen less commonly. Thickening of the vessel wall and narrowing of the vascular lumen in the renal arterioles result in ischemia, which activates the renin-angiotensin system. This results in hypertension, which is often as severe as malignant hypertension, as seen in this patient with CNS symptoms and papilledema. It is, therefore, important to monitor the blood pressure in scleroderma patients, and the presence of hypertension should alert the physician to the possibility of scleroderma renal crisis. Acute renal failure is also typical of scleroderma renal crisis and is likely secondary to a combination of severe hypertension superimposed on the abnormal renal vasculature.
Another possible cause for a sudden onset of renal crisis is renal artery stenosis secondary to atherosclerosis. However, atherosclerosis is unlikely in a young patient, such as this one, without atherosclerotic risk factors. A bruit is typically present in patients with atherosclerotic disease involving the renal arteries, but a bruit is not seen with scleroderma involvement of the kidneys because only the small arterioles are affected.
Fibromuscular dysplasia can be a cause of renal artery stenosis in young patients. However, the presence of Raynaud phenomenon and GERD make scleroderma the more likely diagnosis.
Sudden-onset renal failure can be seen in hemolytic uremic syndrome (HUS); however, it is predominantly manifested by hematological abnormalities, (i.e., thrombocytopenia and microangiopathic hemolytic anemia), and there is usually an accompanying history of prior diarrhea. HUS is commonly seen in children.
Pheochromocytoma is usually associated with episodes of tachycardia, palpitations, headache, and hypertension.
ACE inhibitors are the agents of choice in the treatment of scleroderma renal crisis since these reverse the angiotensin-induced vasoconstriction. Most patients respond favorably if these drugs are used promptly after the diagnosis, and the goal should be to reduce blood pressure to baseline over 72 hours. The ACE inhibitor of choice in these patients is captopril, given that it has a relatively short time to onset and is the agent with which there is the most clinical experience for scleroderma renal crisis. ACE inhibitors also alleviate renal failure in the majority of patients in the long term, although they may temporarily worsen renal failure in the short term. Since ACE inhibitors result in efferent arteriole vasodilation, there may be a mild drop in GFR and subsequent worsening of creatinine, which is already elevated in this patient as is commonly seen in scleroderma renal crisis. Creatinine should be closely monitored in these patients, but generally any increase in creatinine is mild and does not warrant cessation of the ACE inhibitor. While ACE inhibitors are generally avoided in most patients with acute renal failure, scleroderma renal crisis is an exception to this general rule as long as renal function is closely monitored.
Given that this patient has malignant hypertension with CNS manifestations, a second agent, such as intravenous nitroprusside, is needed to acutely lower the patient's blood pressure. This should be done cautiously as a sudden reduction of blood pressure is not favorable because this can further compromise renal perfusion and result in acute tubular necrosis. Only one dose of nitroprusside is generally necessary to gain control of the patient's blood pressure acutely as the captopril takes effect.
This patient's presentation is most consistent with systemic sclerosis, also known as scleroderma. Many patients with scleroderma develop pulmonary fibrosis, which is likely the cause of this patient's shortness of breath. Pulmonary fibrosis is often associated with dry cough and a ''velcro'' like sound on pulmonary auscultation. Many patients with scleroderma have severe gastroesophageal reflux symptoms due to hypomotility of the esophagus and incompetence of the lower esophageal sphincter. A cardiac heave is sometimes found with heart failure, which can be an additional manifestation of scleroderma. The telangiectasias noted around this patient's lips likely represent skin involvement of scleroderma. It is important to note that some patients may have many of the systemic manifestations of the disease without the characteristic skin sclerosis. Because the telangiectasias are the only skin manifestation, this patient may have the limited cutaneous subcategory of scleroderma. Anti-centromere antibody is the autoantibody seen most commonly with this disorder.