In a patient with systemic sclerosis presenting with hypertension and renal failure, what is the likely diagnosis?

In a patient with systemic sclerosis, presenting with hypertension and renal failure, the most likely diagnosis is scleroderma renal crisis. This condition is characterized by the sudden onset of severe hypertension, acute renal failure, and the presence of underlying systemic sclerosis, commonly known as scleroderma.

Scleroderma renal crisis is particularly noted for its rapid progression and can occur unpredictably, often in patients who have diffuse scleroderma. The mechanism behind this condition involves renal microvascular injury leading to a severe reduction in renal perfusion, which subsequently results in elevated blood pressure and a decline in renal function.

The distinguishing features that support this diagnosis include the patient's history of systemic sclerosis, acute onset of symptoms, and the specific combination of hypertension and renal failure. Management typically involves the aggressive control of blood pressure, often using angiotensin-converting enzyme (ACE) inhibitors, which have been shown to be effective in this scenario.

Other options present conditions that involve hypertension and renal failure but are less characteristic or applicable in the context of systemic sclerosis. Renal artery stenosis can lead to hypertension and renal impairment but is not specifically tied to systemic sclerosis. Chronic glomerulonephritis and diabetic nephropathy are also associated with renal failure, but