Ultrasound-based computer-aided diagnosis for cytologically indeterminate thyroid nodules with different radiologists.

PURPOSE: To evaluate a computer-aided diagnosis (CAD) technique in predicting malignancy for cytologically indeterminate thyroid nodules (TNs) as compared with different experienced radiologists. METHOD: 436 patients with 436 cytologically indeterminate TNs on fine-needle aspiration cytology (FNAC) were included and all were confirmed by surgical pathology. They were retrospectively analyzed with respect to ultrasound (US) characteristics using a commercially available CAD system (AmCAD-UT; AmCad BioMed, Taiwan, China) and reviewed by one junior and one senior radiologists.The CAD system and different experienced radiologists stratified the risk of malignancy using ACR TI-RADS category. The diagnostic performance by different experienced radiologists independently and after consulting the CAD (different experienced radiologists + CAD) and by the CAD alone were compared. RESULTS: The different experienced radiologists showed significantly higher specificities than the CAD system alone. The combination of radiologist and CAD system showed improved diagnostic performance with an AUC (Area under the curve) of 0.740 in the senior radiologist and 0.677 in the junior radiologist, as compared with CAD (AUC: 0.585) alone (all P < 0.05). The combination of senior radiologist and CAD system had the highest diagnostic performance (AUC: 0.740) and specificity (68.9%) compared to the others (all P < 0.05). CONCLUSION: The CAD system may play the potential role as a decision-making assistant alongside radiologists for differential diagnosis of TNs with indeterminate cytology.

Rapid and Wash-Free Time-Gated FRET Histamine Assays Using Antibodies and Aptamers.

Histamine (HA) is an indicator of food freshness and quality. However, high concentrations of HA can cause food poisoning. Simple, rapid, sensitive, and specific quantification can enable efficient screening of HA in food and beverages. However, conventional assays are complicated and time-consuming, as they require multiple incubation, washing, and separation steps. Here, we demonstrate that time-gated Förster resonance energy transfer (TG-FRET) between terbium (Tb) complexes and organic dyes can be implemented in both immunosensors and aptasensors for simple HA quantification using a rapid, single-step, mix-and-measure assay format. Both biosensors could quantify HA at concentrations relevant in food poisoning with limits of detection of 0.19 µg/mL and 0.03 µg/mL, respectively. Excellent specificity was documented against the structurally similar food components tryptamine and l-histidine. Direct applicability of the TG-FRET assays was demonstrated by quantifying HA in spiked fish and wine samples with both excellent concentration recovery and agreement with conventional multistep enzyme-linked immunosorbent assays (ELISAs). Our results show that the simplicity and rapidity of TG-FRET assays do not compromise sensitivity, specificity, and reliability, and both immunosensors and aptasensors have a strong potential for their implementation in advanced food safety screening.

Mimotope-Based Immunoassays for the Rapid Analysis of Mycotoxin: A Review.

Mycotoxins are toxic contaminants in foods and feeds that are naturally occurring and largely unavoidable. Determining their contents in these products is essential to protect humans from harm. Immunoassays of mycotoxins have been well-established because they are fast, sensitive, simple, and cost-effective. However, a major limitation of immunoassays is the requirement of toxic mycotoxins as competing antigens, standards, or competing tracers. Mimotopes are peptides or proteins that can specifically bind to antibodies and compete with analytes for binding sites by mimicking antigenic epitopes. They can be employed as substitutes for competing antigens, standards, or competing tracers to avoid use of mycotoxins. This review summarizes the production and functionalization of the two main kinds of mimotopes, mimic peptides and anti-idiotypic antibodies (Ab2), and their applications in rapid analysis of mycotoxins.

Rational hapten design to produce high-quality antibodies against carbamate pesticides and development of immunochromatographic assays for simultaneous pesticide screening.

Carbamate pesticides (CPs) are the most used pesticides in agricultural production and pest control. In this study, carbofuran, isoprocarb and carbaryl were employed as models, and a general hapten strategy based on carbamate moiety recognition was proposed. Molecular modeling of the three-dimensional (3D) structure and surface electrostatic potential of the CPs indicated that the amide group formed by conjugation significantly influenced recognition by antibodies. The proposed strategy was used to obtain three sensitive and specific monoclonal antibodies (mAbs) with IC50 values of 1.4 ng/mL, 8.4 ng/mL and 13.8 ng/mL for carbofuran, isoprocarb and carbaryl, respectively. Negligible cross-reactivity (%) with analogs was observed, except for fenobucarb (84.6%) for isoprocarb. The obtained antibodies were used to develop an immunochromatographic assay (ICA) to simultaneously and quantitatively detect the three CPs. A strip reader was used to determine the limits of quantitation (LOQs) as 0.05 ng/mL (carbofuran), 31.3 ng/mL (isoprocarb) and 31.3 ng/mL (carbaryl). The recoveries of cucumber and Chinese cabbage samples ranged from 76% to 111%, with CVs from 1.3% to 10.6%, indicating good potential for the rapid simultaneous detection of multiple pesticide residues in a large batch of samples.

Development of a sensitive non-competitive immunoassay via immunocomplex binding peptide for the determination of ethyl carbamate in wine samples.

Ethyl carbamate is a group of 2A carcinogen ubiquitously existed in fermented foods. The monitoring of its residues was important for evaluating the potential risk to human beings. Immunoassays with good accuracy and simplicity are great analytical tools for small molecule contaminants. However, it is typically confined in a competitive mode for small molecules with drawback of the sensitivity curbing. In this work, three different phages displayed peptides with capability of identifying the xanthyl ethyl carbamate immunocomplex were isolated from phage library. The binding mechanism of peptides and immunocomplex was studied by computer-assisted simulation. Results indicated that the xanthydrol group of xanthyl ethyl carbamate and the Asn-32 and Asn-92 residues of the antibody light chain were mainly responsible for binding. Simultaneously, a sensitive non-competitive immunoassay for detecting ethyl carbamate in wine samples was developed. The established method exhibited a limit of detection of 5.4 ng/mL and a linear range from 8.7 ng/mL to 32 ng/mL for wine samples. In comparison with the conventional competitive immunoassay, the sensitivity of the proposed non-competitive immunoassay was improved by 17-fold. The results of the immunoassay were validated by a standard ultra-performance liquid chromatography-quadrupole/orbitrap high-resolution mass spectrometry, which illustrated good reliability of the proposed assay.

Improving the diagnosis of AUS/FLUS thyroid nodules using an algorithm with combination of BRAFV600E mutation analysis and ultrasound pattern-based risk stratification.

PURPOSE: To propose a diagnostic algorithm for improving the diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) thyroid nodules. METHODS: This study retrospectively enrolled 77 consecutive patients with 81 AUS/FLUS nodules who underwent preoperative BRAFV600E mutation analysis. A new diagnostic algorithm was proposed that BRAFV600E mutation analysis for the Fine-needle aspiration cytology specimen was firstly carried out, in which positive BRAFV600E mutation indicated malignancy and classification of the nodules with negative BRAFV600E mutation was further performed based on ultrasound pattern-based risk stratification of American Thyroid Association Guidelines. The diagnostic performance of the new diagnostic algorithm was evaluated. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the receiver operating characteristic curve (AUROC) of new diagnostic algorithm were 94.6%, 84.0%, 91.4%, 86.9%, 90.1%, and 0.893, respectively. The proposed diagnostic algorithm significantly increased the diagnostic performances (AUROC: 0.893 vs. 0.837 and 0.795), sensitivity (94.6% vs. 71.4% and 75.0%), and accuracy (90.1% vs. 79.0% and 77.8%) compared with BRAFV600E mutation analysis alone and ultrasound pattern-based risk stratification alone (all P < 0.05). CONCLUSION: The proposed diagnostic algorithm is helpful for improving the diagnosis of AUS/FLUS nodules, which might be as a routine approach.

Predicting Axillary Lymph Node Metastasis in Patients With Breast Invasive Ductal Carcinoma With Negative Axillary Ultrasound Results Using Conventional Ultrasound and Contrast-Enhanced Ultrasound.

OBJECTIVES: The purpose of this study was to establish a scoring system for predicting axillary lymph node metastasis (ALNM) in patients with breast invasive ductal carcinoma with negative axillary ultrasound (US) results. METHODS: In this retrospective study, 156 breast invasive ductal carcinoma lesions from 156 women were retrospectively enrolled. The features of conventional US and contrast-enhanced ultrasound (CEUS) qualitative enhancement patterns and quantitative enhancement parameters were analyzed. Subsequently, a scoring system was created by a multivariate logistic regression analysis. RESULTS: The results found that 60 patients (38%) showed ALNM. A scoring system was defined as risk score = 1.75 × (if lesion size ≥20 mm) + 1.93 × (if uncircumscribed margin shown on conventional US) + 1.77 × (if coarse or twisting penetrating vessels shown on CEUS). When the risk scores were less than 1.75, 1.75 to 1.93, 1.94 to 3.70, and 3.70 or higher, the risk rates of ALNM were 0% (0 of 9), 10.7% (5 of 46), 29.2% (14 of 48) and 77.4% (41 of 53), respectively. In comparison with conventional US alone, the scoring system using the combination of conventional US and CEUS showed better discrimination ability in terms of the area under the curve (0.830 versus 0.777; P = .037). CONCLUSIONS: A scoring system based on conventional US and CEUS may improve the prediction of ALNM.

Production of a specific monoclonal antibody for 1-naphthol based on novel hapten strategy and development of an easy-to-use ELISA in urine samples.

1-naphthol (1-NAP) is the main metabolite of pesticide carbaryl and naphthalene, and is also a genotoxic and carcinogenic intermediate in the synthesis of organic compound, dyes, pigment and pharmaceutical industry. In this work, two novel haptens were designed and synthesized for developing a competitive indirect enzyme-linked immunosorbent assay (ciELISA) method for 1-NAP in urine samples. The assay showed a limit of detection of 2.21 ng/mL and working range from 4.02 ng/mL to 31.25 ng/mL for 1-NAP in optimized working buffer. The matrix effect of samples was eliminated via 15-fold dilution of optimized working buffer. Good average recoveries (102.4%-123.4%) with a coefficient of variation from 11.7% to 14.7% was obtained for spiked urine samples. Subsequent instrument verification test showed good correlation between the results of ciELISA and high-performance liquid chromatography. The developed ciELISA is a high-throughput tool to monitor 1-NAP in urine, which can provide technical support for the establishment of biological exposure level for the exposure to carbaryl, naphthalene and other related pollutants.

Suspicious ultrasound and clinicopathological features of papillary thyroid carcinoma predict the status of TERT promoter.

PURPOSE: To investigate the value of ultrasound (US) and clinicopathological features of papillary thyroid cancer (PTC) in predicting Telomerase Reverse Transcriptase (TERT) promoter mutations. METHODS: Preoperative US images of 351 surgically confirmed PTCs were evaluated in terms of PTCs size and US features. The basic clinicopathological features were also retrieved. Univariate and multivariate analyses were performed to identify the risk factors for TERT promoter mutations. A scoring system was developed based on the cumulative number of risk factors. The area under the receiver operating characteristic curve (AUC) and cut-off value were calculated to evaluate the diagnostic performance of the scoring system for predicting TERT promoter mutations. RESULTS: TERT promoter mutations were found in 4.84% (17/351) of patients with PTCs. Patient age >50 years (OR: 6.244, P = 0.006), multifocality (OR: 21.071, P = 0.022), taller-than-wide shape (OR: 4.934, P = 0.029), microlobulated margin (OR: 4786, P = 0.032), and capsule contact or involvement (OR: 4.668, P = 0.030) were independent risk factors for TERT promoter mutations. TERT promoter mutations were relevant to more suspicious US and clinicopathological features than TERT promoter wild-type PTC (median, 4 vs. 1, P < 0.001). The cut-off value was 2.5 and the associated AUC was 0.908 (P < 0.001). CONCLUSIONS: The probability of TERT promoter mutations increases along with the suspicious US features and clinicopathological characteristics, which may help to recognize patients who deserve a different approach, in terms of management and follow-up, in view of the worst outcome associated to this mutation.

PSA targeted dual-modality manganese oxide-mesoporous silica nanoparticles for prostate cancer imaging.

Studies have shown the potential of nanomaterials for the accurate and early detection of cancer. The aim of the present study was to design and evaluate the value of prostate-specific membrane antigen (PSA)-targeted manganese oxide-mesoporous silica nanoparticles (Mn-Msns) for the detection of prostate cancer. Mn-Msns were prepared, and then conjugated with the PSA antibody and Cy7 to create the multimodality PSA-Mn-Msn-Cy7. Their particle size, zeta potential, stability and magnetic resonance imaging (MRI) features of the nanoparticles were characterized. Optical and MR imaging were evaluated in cell and tumor-bearing mouse models. The Mn in tissues was measured by inductively coupled plasma mass spectrometry. The fabricated nanoparticles were stable and showed good T1relaxivity. The targeted nanoparticles accumulated to a great extent in prostate cancer cells in vitro but not in noncancerous cells. In vivo studies further demonstrated a targeted distribution of PSA-Mn-Msn-Cy7 to cancer tissues as shown by high optical and T1 signals. The targeted distribution was also confirmed by determining the Mn content in the cancer tissues. Our data demonstrate that PSA targeted fluorescence and MR dual-functional nanoparticle can visualize prostate cancer and can be used as NIRF/MR contrast agents.

A rapid and simple fluorescence enzyme-linked immunosorbent assay for tetrabromobisphenol A in soil samples based on a bifunctional fusion protein.

Tetrabromobisphenol A (TBBPA) is the largest brominated flame retardant which can be released to environment and cause long-term hazard. In this work, we developed a rapid and highly sensitive fluorescence enzyme-linked immunosorbent assay (FELISA) for monitoring of TBBPA in soil samples. TBBPA specific nanobody derived from camelid was fused with alkaline phosphatase to obtain the bi-functional fusion protein, which enable the specific binding of TBBPA and the generation of detection signal simultaneously. The assay showed an IC50 of 0.23 ng g-1, limit detection of 0.05 ng g-1 and linear range from 0.1 to 0.55 ng g-1 for TBBPA in soil samples. Due to the high resistance to organic solvents of the fusion protein, a simple pre-treatment by using 40% dimethyl sulfoxide (DMSO) as extract solvent can eliminate matrix effect and obtain good recoveries (ranging from 93.4% to 112.4%) for spiked soil samples. Good relationship between the results of the proposed FELISA and that of liquid chromatography tandem mass spectrometry (LC-MS/MS) was obtained, which indicated it could be a powerful analytical tool for determination of TBBPA to monitor human and environmental exposure.

A full-automated magnetic particle-based chemiluminescence immunoassay for rapid detection of cortisol in milk.

A sensitive full-automated micromagnetic particles (MMPs) based competitive chemiluminescent immunoassay (CLIA) was developed to detect cortisol in milk. Polyclonal antibody (pAb) with good specificity against cortisol was produced. The antigen (cortisol-OVA) was labeled with acridinium ester (cortisol-OVA-AE) as signal tracer. During the detection, the free cortisol in sample will compete with cortisol-OVA-AE for binding to pAb. To capture pAb, MMPs conjugated with goat anti-rabbit IgG was added. The whole immunoassay process (exclude sample pretreatment) was performed by automatic chemiluminescence immunoassay instrument, which could consume less test time (within 40 min) and avoid error from manual operation. The method showed a good detection limit of 0.12 ng/mL, a broad linear range from 0.42 to 72.27 ng/mL for cortisol detection, negligible cross-reactivity with related analogues and satisfied recovery (84.3%-102.3%) for spiked milk samples test. Simultaneously, since the results of proposed method had no significant difference with those of LC-MS/MS, the proposed method was confirmed to have a potential applicability for rapidly monitoring cortisol in the food.

Shear wave speed imaging of breast lesions: Speed within the lesion, fat-to-lesion speed ratio, or gland-to-lesion speed ratio?

OBJECTIVE: To evaluate the diagnostic performance of shear wave speed (SWS) within the lesion, fat-to-lesion speed ratio (FLR), and gland-to-lesion speed ratio (GLR) for differentiation between benign and malignant breast lesions using a novel SWS imaging technique. METHODS: From April 2016 to June 2016, 182 breast lesions were prospectively included in the study. For each lesion, SWS-lesion, FLR, and GLR were calculated. Pathological results were used as the reference standard. Receiver operating characteristic curves (ROC) were plotted to assess the diagnostic performance. RESULTS: Of the 182 lesions, 142 (78.0%) were benign and 40 (22.0%) were malignant. Significant differences were found between benign and malignant lesions in SWS-lesion, FLR and GLR (2.12±0.64 m/s vs 3.87±1.45 m/s, 1.63±0.61 vs 2.60±1.04, and 1.33±0.39 vs 2.08±0.78, respectively. All P < 0.001). The optimal cut-off values of SWS-lesion, FLR, GLR were 2.88 m/s, 2.31 and 1.51, respectively. The diagnostic performance of SWS-lesion in terms of AUC was the highest (i.e. AUC = 0.845), in comparison with FLR and GLR alone or their combination. The associated sensitivity, specificity, and accuracy for SWS-lesion were 75.0%, 89.4%, and 86.3%, respectively. CONCLUSION: SWS-lesion is a valuable and sufficient method for differentiation between benign and malignant breast lesions.

Comparison of fine needle aspiration and non-aspiration cytology for diagnosis of thyroid nodules: A prospective, randomized, and controlled trial.

OBJECTIVES: To compare the sampling efficiency and diagnostic performance of ultrasound (US)-guided fine-needle aspiration cytology (FNAC) and fine-needle non-aspiration cytology (FNNAC) for thyroid nodules. MATERIALS AND METHODS: 629 thyroid nodules in 629 cases (477 females, 152 males) were randomly subjected to FNAC or FNNAC from Jun 2014 to Feb 2015. Diagnostic performance was calculated in reference to the histological findings or follow-up results. RESULTS: 629 patients (152 men, 477 women) with 629 thyroid nodules were enrolled in the study. Pathological results were obtained in 173 nodules and benign nodules at FNA with more than six months' follow-up were found in 65 nodules. Tumor size for FNAC ranges from 3.0 to 51.0 mm (mean±SD; 10.2±6.9 mm); whereas FNNAC (2.0-43.0 mm; 11.9±7.7 mm). Non-diagnostic results were found in 7.59% (24/316) of FNNAC procedures and 7.59% (25/313) of FNAC (P > 0.05). Determinate and indeterminate results were found in 50.63% (160/316) and 41.77% (132/316) of FNNAC procedures, whereas 58.15% (182/313) and 33.87% (106/313) of FNAC (P < 0.05). In order to obtain determinate cytological results, FNAC might be more suitable than FNNAC for diagnosis of nodules with hypovascularity (51.38% vs. 41.78%, P < 0.05) and macrocalcifications (9.72% vs. 6.50%, P < 0.05). No US and Color-Doppler US characteristics, such as the presence of hypervascularity (P > 0.05), microcalcifications (P > 0.05), internal component (P > 0.05), or size(P > 0.05), were significantly different to obtain determinate cytological results between the FNAC and FNNAC groups. The sensitivity, specificity, positive predictive value, negative predictive value, accuracy of FNAC and FNNAC were as follows: 96.67% vs. 100%, 89.74% vs. 96.5%, 87.88% vs. 96.97%, 97.22% vs. 100%, 92.75% vs.98.36%, respectively (all P > 0.05). CONCLUSIONS: Both FNAC and FNNAC are effective for diagnosis of thyroid nodules. However, FNAC is more effective than FNNAC to acquire determinate cytological results for nodules which US present hypovascularity and macrocalcifications.

The diagnostic performance of shear wave speed (SWS) imaging for thyroid nodules with elasticity modulus and SWS measurement.

To evaluate the diagnostic performance of a new technique of shear wave speed (SWS) imaging for the diagnosis of thyroid nodule with elasticity modulus and SWS measurement. 322 thyroid nodules in 322 patients (216 benign nodules, 106 malignant nodules) were included in this study. All the nodules received conventional ultrasound (US) and SWS imaging (Aplio500, Toshiba Medical Systems, Japan) before fine-needle aspiration (FNA) and/or surgery. The values of E-max and E-mean with elastic modulus (61.27 ± 36.31 kPa and 31.89 ± 19.11 kPa) or SWS (4.45 ± 1.49 m/s and 3.26 ± 2.71 m/s) in malignant nodules were significantly higher than those in benign lesions (29.18 ± 18.62 kPa and 15.85 ± 6.96 kPa, or 2.98 ± 0.85 m/s and 2.19 ± 0.42 m/s, all P < 0.001). No significant differences in area under the curve (AUC) between the SWS imaging parameters were found (all P > 0.05). In multivariate logistic regression analysis, E-max (m/s) with SWS was identified to be the strongest independent predictor for malignant nodules (odds ratio [OR] = 16.760), followed by poorly-defined margin (OR = 7.792), taller-than-wide shape (OR = 3.160), micro-calcification (OR = 2.422), and E-max (kPa) with elastic modulus (OR = 0.914). The AUC was 0.813 for E-max with SWS (m/s) and 0.796 for E-max with elastic modulus (kPa). With cut-off SWS value of 3.52 m/s in E-max, sensitivity of 69.8%, specificity of 81.5%, and accuracy of 77.6% were achieved. SWS imaging is a valuable tool in predicting thyroid malignancy. E-max with SWS measurement is the strongest independent predictor for thyroid malignancy.

Contrast-enhanced ultrasound aids in the detection of prostate rhabdomyosarcoma: A case report and literature review.

Prostate sarcoma is a rare malignancy with an extremely poor prognosis. The extremely low morbidity and atypical clinical symptoms contribute to a missed diagnosis. The typical features of prostate sarcoma in transrectal ultrasound (US) and magnetic resonance imaging, such as a markedly enlarged volume and irregular prostatic contours, cannot usually be found until dysuria or even uroschesis occurs, and may then be too late to treat. However, there appears to no specific tumor marker for the disease in the serum. The present study reports a case of a young male patient who was diagnosed with prostate rhabdomyosarcoma. This was, to the best of our knowledge, the first case of this diagnosis using contrast-enhanced US (CEUS) when the symptoms were not severe. In this case, the intralesional non-enhancement areas and rim-like hyper-enhancement around the lesion were considered to be the main CEUS features of prostate rhabdomyosarcoma. The present study also reviews the associated literature.

Differentiation of benign and malignant focal liver lesions: value of virtual touch tissue quantification of acoustic radiation force impulse elastography.

The purpose of this study was to investigate the value of virtual tissue quantification (VTQ) of acoustic radiation force impulse elastography for the differential diagnosis of benign and malignant focal liver lesions (FLLs). Thus, a total of 134 FLLs in 134 patients were included. VTQ measurement was performed for each lesion in which the shear wave velocity (SWV) was measured. The difference in SWV and SWV ratio of FLL to surrounding liver between malignant and benign FLLs was evaluated, and the cutoff value was investigated. Receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic performance. A total of 134 lesions including 55 (41.0%) malignant FLLs and 79 (59.0%) benign ones were analyzed. The SWV of malignant and benign FLLs was 2.95 ± 1.00 m/s and 1.69 ± 0.89 m/s, respectively. Significant difference in SWV was presented between malignant and benign FLLs (p < 0.001). The SWV ratio of each FLL to the surrounding liver parenchyma was 1.83 ± 1.32 for malignant and 1.26 ± 0.78 for benign FLLs (p < 0.001). The area under the ROC curve in distinguishing malignant from benign lesions was 0.824 for SWV and 0.660 for SWV ratio. The cutoff value for differential diagnosis was 2.13 m/s for SWV and 1.37 for SWV ratio. The associated sensitivity and specificity were 83.3 and 77.9% for SWV and 59.6 and 77.3% for SWV ratio, respectively. In conclusion, VTQ provides quantitative stiffness information of FLLs and is helpful in the differential diagnosis between malignant and benign FLLs, particularly for the patients who are not candidates for contrast-enhanced imaging such as CT, MRI or contrast-enhanced ultrasound.

Acoustic radiation force impulse imaging for noninvasive evaluation of renal parenchyma elasticity: preliminary findings.

OBJECTIVE: To evaluate the diagnostic value of acoustic radiation force impulse (ARFI) to test the elasticity of renal parenchyma by measuring the shear wave velocity (SWV) which might be used to detect chronic kidney disease (CKD). METHODS: 327 healthy volunteers and 64 CKD patients were enrolled in the study. The potential influencing factors and measurement reproducibility were evaluated in the healthy volunteers. Correlations between SWV and laboratory tests were analyzed in CKD patients.?Receiver-operating characteristic curve (ROC) analyses were performed to assess the diagnostic performance of ARFI. RESULTS: The SWV of healthy volunteers correlated significantly to age (r = -0.22, P<0.001, n = 327) and differed significantly between men and women (2.06±0.48 m/s vs. 2.2±0.52 m/s, P = 0.018, n = 327). However, it did not correlate significantly to height, weight, body mass index, waistline, kidney dimension and the depth for SWV measurement (n = 30). Inter- and intraobserver agreement expressed as intraclass coefficient correlation were 0.64 (95% CI: 0.13 to 0.82, P = 0.011) and 0.6 (95% CI: 0.31 to 0.81, P = 0.001) (n = 40). The mean SWV in healthy volunteers was 2.15±0.51 m/s, while was 1.81±0.43 m/s, 1.79±0.29 m/s, 1.81±0.44 m/s, 1.64±0.55 m/s, and 1.36±0.17 m/s for stage 1, 2, 3, 4 and 5 in CKD patients respectively. The SWV was significantly higher for healthy volunteers compared with each stage in CKD patients. ARFI could not predict the different stages of CKD except stage 5. In CKD patients, SWV correlated to e-GFR (r = 0.3, P = 0.018), to urea nitrogen (r =  -0.3, P = 0.016), and to creatinine (r =  -0.41, P = 0.001). ROC analyses indicated that the area under the ROC curve was 0.752 (95% CI: 0.704 to 0.797) (P<0.001). The cut-off value for predicting CKD was 1.88 m/s (sensitivity 71.87% and specificity 69.69%). CONCLUSION: ARFI may be a potentially useful tool in detecting CKD.