No abstract

SummaryAs judged by the American College of Radiology Appropriateness Criteria, renal Doppler ultrasonography is the most appropriate imaging test in the evaluation of AKI and has the highest level of recommendation. Unfortunately, nephrologists are rarely specifically trained in ultrasonography technique and interpretation, and important clinical information obtained from renal ultrasonography may not be appreciated. In this review, the strengths and limitations of grayscale ultrasonography in the evaluation of patients with AKI will be discussed with attention to its use for (1) assessment of intrinsic causes of AKI, (2) distinguishing acute from chronic kidney diseases, and (3) detection of obstruction. The use of Doppler imaging and the resistive index in patients with AKI will be reviewed with attention to its use for (1) predicting the development of AKI, (2) predicting the prognosis of AKI, and (3) distinguishing prerenal azotemia from intrinsic AKI. Finally, pediatric considerations in the use of ultrasonography in AKI will be reviewed.

HALT-PKD consists of two randomized trials comparing treatment with an angiotensin converting inhibitor (ACEI)-angiotensin receptor blocker (ARB) combination vs ACEI alone and standard vs low blood pressure target in Study A (eGFR >60 ml/min/1.73 m2) and ACEI-ARB vs ACEI alone in Study B (eGFR 25-60 ml/min/1.73 m2). It includes the largest cohort of systematically studied ADPKD patients (558 A and 486 B) to date. We used correlation and multiple regression cross-sectional analyses to ascertain associations of baseline parameters with total kidney (TKV) and liver (TLV) or liver cyst (LCV) volumes measured by MRI in Study A and with eGFR in both studies. Lower eGFR and higher natural log transformed urine albumin excretion are independently associated with larger natural log transformed TKV adjusted for height (HtTKV). Higher BSA is independently associated with higher ln(HtTKV) and lower eGFR. Men have larger HtTKV and smaller LCV than women. A weak correlation was found between ln(HtTKV) and ln(HtTLV) or ln(LCV) in women only. Women have higher urine aldosterone excretions and lower plasma potassium levels. In summary, this analysis 1) confirms a strong association between renal volume and functional parameters, 2) shows that gender and other factors differentially affect the development of polycystic disease in the kidney and liver, and 3) suggests an association between anthropomorphic measures reflecting preand/or post-natal growth and the severity of the disease.

SummaryBackground and objectives Autosomal dominant polycystic kidney disease (ADPKD) is associated with a substantial cardiovascular disease burden including early onset hypertension, intracranial aneurysms, and left ventricular hypertrophy (LVH). A 41% prevalence of LVH has been reported in ADPKD, using echocardiographic assessment of LV mass (LVM). The HALT PKD study was designed to assess the effect of intensive angiotensin blockade on progression of total kidney volume and LVM. Measurements of LVM were performed using cardiac magnetic resonance (MR). Design, setting, participants, & measurementsFive hundred forty-three hypertensive patients with GFR Ͼ60 ml/min per 1.73 m 2 underwent MR assessment of LVM at baseline. LVM was adjusted for body surface area and expressed as LVM index (LVMI; g/m 2 ).Results Baseline BP was 125.1 Ϯ 14.5/79.3 Ϯ 11.6 mmHg. Average duration of hypertension was 5.79 years. Prior use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was present in 59.5% of patients. The prevalence of LVH assessed using nonindexed LVM (g) was 3.9% (n ϭ 21, eight men and 13 women) and 0.93% (n ϭ 5, one man and four women) using LVMI (g/m 2 ). In exploratory analyses, the prevalence of LVH using LVM indexed to H 2.7 , and the allometric index ppLVmass HW , ranged from 0.74% to 2.23% (n ϭ 4 to 12). Multivariate regression showed significant direct associations of LVMI with systolic BP, serum creatinine, and albuminuria; significant inverse associations with LVMI were found with age and female gender. ConclusionsThe prevalence of LVH in hypertensive ADPKD patients Ͻ50 years of age with short duration of hypertension, and prior use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers is low. Early BP intervention in ADPKD may have decreased LVH and may potentially decrease cardiovascular mortality.

Although many individuals with ADPKD have a linear decline in eGFR, prolonged intervals of stable GFRs occur in a substantial fraction. Lower body mass index was associated with more stable kidney function in early ADPKD.