Multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney: CT and MRI findings and clinical characteristic.

PURPOSE: The aim of this study was to clarify the radiologic and clinical characteristics of multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney. METHOD: Fourteen patients with unique and characteristic multiple hemorrhagic subcapsular cortical cysts of the kidney, not categorized in any existing renal cystic diseases, were retrospectively reviewed. The clinical information including age, sex, symptom, family history of renal or renal cystic disease, and laboratory data were collected. CT and MRI findings including distribution, number and size of cysts, and CT attenuation and signal intensity on T1- and T2-weighted MRI of cysts were analyzed. RESULTS: All patients except one were young and none had a family history of renal or renal cystic disease. Common clinical symptoms were flank or abdominal pain and hematuria. In all cases, only the left kidney was involved at initial presentation. Cysts were small (median cyst size, 4-15 mm), numerous, and distributed mainly along the subcapsular cortex of the kidney. Cysts were hyper-attenuated on unenhanced CT, extremely hypointense on T2-weighted MRI, and mildly hyperintense on T1-weighted MRI. All patients except one had normal renal function. Imaging follow-up revealed stable or mildly progressive disease in seven patients. Two patients developed several hemorrhagic subcapsular cortical cysts in the right kidney at follow-up. Three of five patients with a renal pathology specimen showed concurrent IgA nephropathy. CONCLUSION: We have identified a unique renal cystic disease with multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney that has a characteristic manifestation both radiologically and clinically. KEY POINTS: • Multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney is a unique non-familial renal cystic disease with a characteristic manifestation both radiologically and clinically. • Most cases of multiple unilateral subcapsular cortical hemorrhagic cystic disease of the kidney are stable or slowly progressive, and do not require invasive intervention.

Cost-effectiveness of irbesartan 300 mg given early versus late in patients with hypertension and a history of type 2 diabetes and renal disease: a Canadian perspective.

BACKGROUND: The Irbesartan in Reduction of Microalbuminuria trial and the Irbesartan in Diabetic Nephropathy Trial found that irbesartan is renoprotective in patients having hypertension with type 2 diabetes. OBJECTIVE: The objective of this study was to assess whether treatment with irbesartan is cost-effective in Canada relative to conventional care in this patient population and whether it is more cost-effective to treat patients early rather than later in the development of renal disease from the perspective of the Canadian health and social care system. METHODS: The analysis compared 3 alternative strategies for the management of hypertension in patients with type 2 diabetes and early renal disease: (1) conventional hypertensive treatment excluding the use of angiotensin II receptor antagonists (AIIRAs); (2) the early addition of irbesartan (an AIIRA) to conventional treatment; and (3) the late addition of irbesartan to conventional treatment. A Markov model was used to simulate the progression of renal disease (microalbuminuria to death) in hypertensive patients with type 2 diabetes over a 25-year time horizon. Transition probabilities were derived from the 2 randomized controlled trials. A cost-effectiveness analysis was conducted with outcome measured in life-years gained (LYGs). RESULTS: The early addition of irbesartan during microalbuminuria was cost-saving and more effective than both delaying irbesartan treatment until advanced overt nephropathy (AON) (0.45 LYG, Can $54,100 saved) and conventional antihypertensive use (0.62 LYG, $68,400 saved). This was due to the increased drug costs associated with the use of irbesartan being offset by savings arising from delays in the development of overt nephropathy and the subsequent delay to end-stage renal disease (ESRD). Sensitivity analyses confirmed the robustness of the study results. CONCLUSIONS: The early use of irbesartan for patients with hypertension and type 2 diabetes who have yet to develop overt nephropathy is both more effective and less costly than delaying irbesartan treatment until AON and conventional antihypertensive use. Analysis suggests that the earlier irbesartan is added to conventional antihypertensive treatment, the greater the delays in the onset of ESRD and the overall savings in health care resource utilization from the perspective of the Canadian health and social care system.