Contrast-enhanced ultrasonography in chronic glomerulonephritides: correlation with histological parameters of disease activity

Improving Prognostic and Chronicity Evaluation of Chronic Kidney Disease with Contrast-Enhanced Ultrasound Index-Derived Peak Intensity

The capability of contrast-enhanced ultrasound (CEUS) to assess the prognosis and chronicity of chronic kidney disease (CKD) was evaluated in patients diagnosed with CKD in 2014 at Ren Ji Hospital, Shanghai, China. Time-intensity curves and quantitative indexes were created using QLab quantification software. Kidney biopsies were analyzed with α-smooth muscle actin immunohistochemistry. According to the renal chronicity score, patients were divided into four groups: minimal (n = 14), mild (n = 73), moderate (n = 49) and severe (n = 31). Multivariate logistic regression analysis revealed that the derived peak intensity (DPI) was independently associated with the renal chronicity score. Of 167 CKD patients (median follow-up: 30.4 ± 18.7 mo), 31 (18.6%) exhibited CKD progression, with a decline in the glomerular filtration rate of more than 25% or end-stage renal disease. Multivariate Cox regression analysis revealed that a lower DPI was independently associated with CKD progression. This study indicates that DPI is a reliable CEUS parameter for evaluating chronic renal changes and an independent prognostic factor of CKD.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS

PURPOSE

To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam.

METHODS

In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3 years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern.

RESULTS

Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3 years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation.

CONCLUSIONS

CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.

Multiparametric ultrasound in the evaluation of kidney disease in elderly

After the age of 30 years, GFR progressively declines at an average rate of 8 mL/min/1.73 m/decade. A problem of advanced age is that the evaluation of renal function on the basis of indicators valid in young adults, such as creatininemia, is unreliable. In fact, many patients with chronic renal failure may have serum creatinine levels within the normal range even if they have a significant reduction in renal function. Ultrasound has become a routine method of investigation in renal disease: kidney size and parenchymal echogenicity are considered markers of renal function, so US is useful in assessing the presence and degree of renal failure. CEUS is useful in the evaluation of kidney disease in the elderly: the increased hemodynamic resistance of renal microvessels reduces perfusion in the renal cortex, so fewer microbubbles enter the renal cortex. EcoColor and EcoDoppler are also useful in the evaluation of senile alterations: here, the distribution of color-signals, as compared to that in the young adult population, appears more attenuated, limited to intersegmental and interlobar districts. Among the ecoDoppler parameters, the resistance index can be considered a marker of renal damage progression, with attention needing to paid to possible concomitant confounding factors. Ultrasonography, color-Doppler and CEUS are a non-invasive and convenient modality for managing kidney disease; their integration with anamnestic, objective and laboratory data permits fast and reliable clinical, diagnostic, and therapeutic classification. It also allows early therapeutic intervention and, ultimately, improvements in patient management.