Gray Scale Ultrasound, Color Doppler Ultrasound, and Contrast-Enhanced Ultrasound in Renal Parenchymal Diseases

The added value of superb microvascular imaging for renal cortical thickness measurement in chronic kidney disease

PURPOSE

The aim of this study was to evaluate renal parenchymal thickness and renal cortical thickness measurements on brightness mode ultrasound (B-mode US) and B-mode US + Superb Microvascular Imaging (SMI) technique, comparing with computed tomography (CT) or magnetic resonance imaging (MRI) serving as a reference standard.

METHODS

Renal parenchymal thickness and renal cortical thickness measurements were obtained from B-mode US, B-mode US + SMI, and CT/MRI in a group of healthy subjects and a group of patients with chronic kidney disease (CKD). The mean differences and correlations of renal parenchymal thickness and renal cortical thickness were analyzed using dependent pair t-test and Pearson's correlation, respectively.

RESULTS

The mean difference in renal cortical thickness measurements between B-mode US + SMI and CT/MRI was lower than the mean difference between B-mode US alone and CT/MRI. Additionally, renal cortical thickness measured using B-mode US + SMI showed a stronger correlation with values obtained from CT/MRI than values measured using standard B-mode US alone.

CONCLUSION

The measurement of renal cortical thickness by B-mode US + SMI is more accurate than that by B-mode US alone.

Evaluation of image-pro plus assisted superb microvascular imaging for differential diagnosis of renal masses

OBJECTIVE

Previous research on diagnostic assessment by superb microvascular imaging (SMI) were based on qualitative or semi-quantitative assessments of vascularity, which may be subjective and unrepeatable by different sonographers. This study aimed to evaluate diagnostic performance of SMI Image-pro Plus (IPP) based vascular index (VI) for malignant renal masses.

METHOD

We retrospectively reviewed 222 masses in 214 patients who underwent SMI between August 2019 and August 2022 in our study. We evaluated the diagnostic performance of blood flow via Alder grade, VI based on both IPP and SMI.

RESULTS

The kappa consistency of the Adler grade and VI for renal masses was classified among different observers were 0.765 and 0.824. The intra-observers correlation ecoefficiency (ICC) were 0.727 and 0.874. Benign renal masses were mainly Adler grade 0, grade I, and grade II, VI was 4.30 ± 4.27 (Range 0.98-16.42); while malignant masses were mainly Adler grade III, VI was 14.95 ± 10.94 (Range 0.79-56.89). VI was higher in malignant than benign masses (t = 15.638, P < 0.01). Among the malignant masses, the mean VI in clear cell renal cell carcinoma was higher than that in papillary renal cell carcinoma and chromophobe renal cell carcinoma (F = 30.659, P < 0.01). The sensitivity, specificity and accuracy of SMI were 80.00%, 71.15%, and 78.64%, respectively. The sensitivity, specificity, and accuracy were 60.59%, 88.46%, and 80.18% by using a VI of 7.95 as the cutoff value to identify malignant lesions from benign masses yielded. VI had better diagnostic efficiency than ultrasonic characteristics and Adler grade in benign and malignant differential diagnosis (Z = 4.851, P < 0.01; Z = 2.732, P < 0.01).

CONCLUSION

VI was higher in malignant than benign in renal masses. In malignant masses, VI in CCRCC was higher than that in papillary renal cell carcinoma and ChRCC. As a noninvasive examination, it had important clinical significance in the differential diagnosis of renal masses. VI from IPP may assist sonographer in distinguish renal malignances as a quantitative tool for vascularity.

Renal and Genitourinary Ultrasound Evaluation in Emergency and Critical Care: An Overview

Renal and genitourinary ultrasound are fundamental resources employed by emergency and critical care healthcare providers to make prompt diagnoses and perform ultrasound-guided procedures. At the bedside, ultrasound can aid in the diagnosis of relevant pathologies, such as post-renal obstruction or kidney stones, and life-threatening conditions such as aortic dissection or hemoperitoneum. A narrative overview was performed, providing an updated review of renal and genitourinary ultrasound for emergency and critical care healthcare providers, emphasizing its advantages and the latest advances in the field. A thorough summary that can be utilized as a guide for emergency and critical care healthcare providers is presented. The daily hemodynamic management of critically ill patients involves the implementation of new protocols, such as VexUS or the evaluation of the renal resistance index. The role of ultrasound in managing acute nephropathy and genitourinary issues is increasingly crucial given its bedside availability, thus this imaging modality not only facilitates the initiation of therapeutic interventions but also provides swift prognostic insights that are vital to provide tailored patient care. As further advances in ultrasound will arise, it is important for healthcare providers to foster the use of these technologies capable of improving patient outcomes.

Evaluation of Hepatic/Renal and Splenic/Renal Echointensity Ratio Using Ultrasonography in Diabetic Nephropathy

The objective of this study is to assess the hepatic/renal and splenic/renal echointensity ratios in ultrasonography in patients with and without diabetic nephropathy. This retrospective study included patients with diabetes mellitus who underwent ultrasound examinations at our hospital between January 2023 and May 2023. Ultrasound examinations were conducted using renal cortical echogenicity and corticomedullary differentiation by using B-mode ultrasonography. The hepatic/renal and splenic/renal echo intensity ratios were compared among study groups (diabetic patients with diabetic nephropathy and without nephropathy). The diabetic nephropathy group exhibited significantly higher right renal echointensity and left renal echointensity compared to the non-nephropathic group. Additionally, the splenic/renal echointensity ratio and hepatic/renal echointensity ratio were significantly lower in the diabetic nephropathy group. Urinary microalbumin levels were significantly correlated with right renal echointensity (r = 0.65, p < 0.001) and left renal echointensity (r = 0.69, p < 0.001). There was also a significant inverse correlation between the urinary albumin and splenic/renal echointensity ratio (r = -0.58, p < 0.001). Ultrasonography, specifically the assessment of hepatic/renal and splenic/renal echointensity ratios, shows promise as a noninvasive and cost-effective method for evaluating morphological changes in the kidneys in patients with diabetic nephropathy. These findings suggest that ultrasonography can be a valuable tool for monitoring the progression of diabetic nephropathy and contributing to its early detection and management.

Shear wave elastography evaluation of kidneys in children with familial mediterranean fever

Background and Aim

Familial Mediterranean fever (FMF) is an autosomal recessive disorder. Typical clinical manifestations are self-limiting attacks of recurrent fever, abdominal pain, arthralgia, and chest pain due to aseptic polyserositis. Renal involvement is common in FMF patients. Shear wave elastography (SWE) is a noninvasive method that provides the measurement of tissue stiffness. In this study, we aimed to show that SWE can be used as an adjunctive method for evaluating renal involvement in children with FMF.

Materials and Methods

Our study group consists of 79 pediatric FMF patients and 79 control individuals. The study was planned prospectively. The variables, such as age, height, weight, and body mass index (BMI) of the patient and control groups, were kept in a similar way in order not to be affected by the differences. The right and left kidney sizes, parenchymal thicknesses, and SWE values in both groups were compared. The parenchymal stiffness degrees of the kidneys were quantified by shear modulus values in kilopascals.

Results

In our study, no statistically significant difference was found between the control and patient groups in terms of the right and left kidney longitudinal dimensions, transverse dimensions, and parenchymal thicknesses. When the kidneys were evaluated in terms of the right and left kidney stiffness values, the stiffness values in the patient group were significantly higher in both kidneys compared with those in the control group (P < 0.001).

Conclusions

SWE can be a noninvasive quantitative imaging method that can be used to evaluate kidney involvement by detecting changes in kidney stiffness in children with FMF.

Automatic Screening of Pediatric Renal Ultrasound Abnormalities: Deep Learning and Transfer Learning Approach

BACKGROUND

In recent years, the progress and generalization surrounding portable ultrasonic probes has made ultrasound (US) a useful tool for physicians when making a diagnosis. With the advent of machine learning and deep learning, the development of a computer-aided diagnostic system for screening renal US abnormalities can assist general practitioners in the early detection of pediatric kidney diseases.

OBJECTIVE

In this paper, we sought to evaluate the diagnostic performance of deep learning techniques to classify kidney images as normal and abnormal.

METHODS

We chose 330 normal and 1269 abnormal pediatric renal US images for establishing a model for artificial intelligence. The abnormal images involved stones, cysts, hyperechogenicity, space-occupying lesions, and hydronephrosis. We performed preprocessing of the original images for subsequent deep learning. We redefined the final connecting layers for classification of the extracted features as abnormal or normal from the ResNet-50 pretrained model. The performances of the model were tested by a validation data set using area under the receiver operating characteristic curve, accuracy, specificity, and sensitivity.

RESULTS

The deep learning model, 94 MB parameters in size, based on ResNet-50, was built for classifying normal and abnormal images. The accuracy, (%)/area under curve, of the validated images of stone, cyst, hyperechogenicity, space-occupying lesions, and hydronephrosis were 93.2/0.973, 91.6/0.940, 89.9/0.940, 91.3/0.934, and 94.1/0.996, respectively. The accuracy of normal image classification in the validation data set was 90.1%. Overall accuracy of (%)/area under curve was 92.9/0.959..

CONCLUSIONS

We established a useful, computer-aided model for automatic classification of pediatric renal US images in terms of normal and abnormal categories.

Kidney Echogenicity and Vesicoureteral Reflux in Children with Febrile Urinary Tract Infection

OBJECTIVE

To evaluate increased kidney echogenicity as a predictor of vesicoureteral reflux (VUR) in young children with first febrile urinary tract infection (UTI).

STUDY DESIGN

We performed a single center retrospective study of hospitalized children with first febrile UTI diagnosed in accordance with the American Academy of Pediatrics guidelines. All patients had kidney bladder ultrasound (KBUS) and voiding cystourethrography. Variables analyzed using χ² test or Mann-Whitney U test as appropriate. Multivariable logistic regression analysis was performed for the abnormal KBUS findings and OR and 95% CI were calculated.

RESULTS

Our cohort included 415 children (830 kidney units) with median age of 5 months (1 month to 5 years) and 80% were female. One hundred thirty-two (31.8%) patients had abnormal KBUS, including increased echogenicity in 45 patients. Overall, 42.2% of patients with increased echogenicity had VUR vs 23.3% with normal ultrasound (P = .013) and 31.1% of patients with increased echogenicity had high-grade III-V VUR vs 8.1% with normal ultrasound (P = .001). In total, 24.3% of kidneys with increased echogenicity had VUR vs 20% with normal ultrasound (P = .246) and 20% of kidneys with increased echogenicity had high-grade III-V VUR vs 9.9%with normal ultrasound (P = .005).

CONCLUSIONS

These data support adding increased kidney echogenicity to the list of other KBUS findings that are helpful in decision making about a need for voiding cystourethrography in young children with first febrile UTI.

Evaluation of Intra-Renal Stiffness in Patients with Primary Aldosteronism

INTORDUCTION

Aldosterone is known to play important role in developing cardiovascular, metabolic, renal damage in hypertensive patients.

AIM

Aim of study was to evaluate parameters obtained by eco-color Doppler study, as non-invasive and easly performed method in asyntomatic patients with Essential Hypertension (EH) and Primary Aldosteronism (PA), without overt organ damage.

METHODS

From April 2019 to March 2020 we consecutively enrolled 73 hypertensive subjects (48 males, 25 women), distinguished in two groups: 30 EH patients (mean age 49.5 ± 18.7 years) and 43 PA patients (mean age 53.1 ± 11.6 years)] [23 with aldosterone-secreting adrenal adenoma (APA), 20 with idiopathic aldosteronism (IHA)].

RESULTS

PA group showed higher renal filtration rate and 24-h urinary excretion of albumin respect to EH; moreover, in PA we found higher Pulsatility Index, altered percentage of Renale Resistance Index, Atrophy Index, and reducted parietal thickness than EH. The correlation study showed that plasma aldosterone were positively correlated with pulsatility index in PA group (right r = 0.35; p < 0.05; left r = 0.36; p < 0.05).

CONCLUSION

parameters obtained through the intra-renal eco-color Doppler examination, easly performed and non-invasive, can be useful in the early-stage identification of subclinical microvascular alterations, especially in PA, condition characterized by increased risk of cardio-vascular remodelling and metabolic alterations.

Contrast-enhanced ultrasound of the kidneys and adrenals in children

Pediatric applications of contrast-enhanced ultrasound (CEUS) are growing. Evaluation of the kidneys and adrenal glands in children using intravenous administration of US contrast agents, however, is still an off-label indication. Pediatric CEUS applications for kidneys are similar to those in adults, including ischemic disorders, pseudo- versus real tumors, indeterminate lesions, complex cystic lesions, complicated pyelonephritis, and abscesses. CEUS applications for evaluation of adrenal glands in children are limited, mainly focusing on the assessment and follow-up of adrenal trauma and the differentiation between an adrenal hemorrhage and a mass. This review addresses the current experience in pediatric CEUS of the kidneys and adrenal glands. By extrapolating the established knowledge for US contrast evaluations in the adult kidney to the pediatric context we can note opportunities for CEUS clinical use in children.

Analysis of Risk Factors for Changes in the Renal Two-Dimensional Image in Gout Patients

OBJECTIVE

To explore the effects of different blood uric acid levels in gout patients on the two-dimensional image of the kidney and the risk factors for gout-related kidney damage for providing clinical evidence to enable early prevention and treatment of gout-related kidney damage.

METHODS

We obtained information of 227 patients with primary gout and estimated the association between two-dimensional kidney images and clinical indicators using binary logistic regression.

RESULTS

Our study showed that different uric acid levels, age, disease course, cystatin C (CysC) level, and γ-glutamyl transpeptidase level were correlated with echo of the renal medulla (P < 0.05). CysC level was correlated with the renal cortex thickness and kidney stones in different uric acid-level groups (P < 0.05). Disease course, aspartate transaminase (AST) level, creatinine (CREA) level, and tophi were risk factors for renal cortex thinning in gout patients (P = 0.045, 0.026, 0.004, 0.006, respectively). The disease course, platelet (PLT) count, and high-density lipoprotein (HDL-C) level were risk factors for kidney stone formation in gout patients (P = 0.037, 0.022, 0.023, respectively), while CysC level and C-reactive protein (CRP) level were risk factors for increased renal medulla echo in these patients (P = 0.022, 0.028, respectively).

CONCLUSION

Our study revealed disease course, AST level, CREA level, tophi, PLT count, HDL-C level, CysC level and CRP level may be important predictors of renal image changes.

Renal elastography measurements in children with acute glomerulonephritis

PURPOSE

The aim of this study was to compare the acoustic radiation force impulse elastography (ARFI-e) values of the renal cortical parenchyma in children with acute glomerulonephritis (AGN) and healthy children, and to determine a cut-off point for the diagnosis of AGN.

METHODS

This prospective study included 30 children with biopsy-proven AGN and 30 healthy children. All the children underwent renal ARFI-e measurements. Values were obtained from the upper, middle, and lower zones of the right kidney parenchyma. A total of nine ARFI-e measurements (three from each zone) were made. Statistical analyses were conducted of the mean elastography values (MEVs) of the children in both groups.

RESULTS

In the patient group, the MEVs measured from the upper, middle and lower zones of the right kidney were 3.42±0.42 m/s, 3.45±0.45 m/s, and 3.39±0.39 m/s (average, 3.42±0.34 m/s), respectively. In the healthy control group, the MEVs measured from the upper, middle, and lower zones of the right kidney were 2.85±0.63 m/s, 2.85±0.68 m/s, and 2.86±0.66 m/s (average, 2.85±0.57 m/s), respectively. The MEVs in all zones were significantly higher in the patient group than in the healthy group (P<0.001). The cut-off values determined to predict AGN in the upper, middle, and lower zones of the kidney were 2.74 m/s (sensitivity, 96.67%; specificity, 46.67%), 2.71 m/s (sensitivity, 96.67%; specificity, 53.33%), and 2.81 m/s (sensitivity, 93.33%; specificity, 56.67%), respectively.

CONCLUSION

The ARFI-e technique can be considered as a non-invasive, easily applicable, auxiliary method for the early diagnosis of AGN.

Improved diagnostics of infectious diseases in emergency departments: a protocol of a multifaceted multicentre diagnostic study

BACKGROUND

The major obstacle in prescribing an appropriate and targeted antibiotic treatment is insufficient knowledge concerning whether the patient has a bacterial infection, where the focus of infection is and which bacteria are the agents of the infection. A prerequisite for the appropriate use of antibiotics is timely access to accurate diagnostics such as point-of-care (POC) testing.The study aims to evaluate diagnostic tools and working methods that support a prompt and accurate diagnosis of hospitalised patients suspected of an acute infection. We will focus on the most common acute infections: community-acquired pneumonia (CAP) and acute pyelonephritis (APN). The objectives are to investigate (1) patient characteristics and treatment trajectory of the different acute infections, (2) diagnostic and prognostic accuracy of infection markers, (3) diagnostic accuracy of POC urine flow cytometry on diagnosing and excluding bacteriuria, (4) how effective the addition of POC analysis of sputum to the diagnostic set-up for CAP is on antibiotic prescriptions, (5) diagnostic accuracy of POC ultrasound and ultralow dose (ULD) computerized tomography (CT) on diagnosing CAP, (6) diagnostic accuracy of specialist ultrasound on diagnosing APN, (7) diagnostic accuracy of POC ultrasound in diagnosing hydronephrosis in patients suspected of APN.

METHODS AND ANALYSIS

It is a multifaceted multicentre diagnostic study, including 1000 adults admitted with suspicion of an acute infection. Participants will, within the first 24 hours of admission, undergo additional diagnostic tests including infection markers, POC urine flow cytometry, POC analysis of sputum, POC and specialist ultrasound, and ULDCT. The primary reference standard is an assigned diagnosis determined by a panel of experts.

ETHICS, DISSEMINATION AND REGISTRATION

Approved by Regional Committees on Health Research Ethics for Southern Denmark, Danish Data Protection Agency and clinicaltrials.gov. Results will be presented in peer-reviewed journals, and positive, negative and inconclusive results will be published.

TRIAL REGISTRATION NUMBERS

NCT04661085, NCT04681963, NCT04667195, NCT04652167, NCT04686318, NCT04686292, NCT04651712, NCT04645030, NCT04651244.

Automated Segmentation of Fetal Ultrasound Images Using Feature Attention Supervised Network

ABSTRACT

Segmentation of anatomical structures from ultrasound images requires the expertise of an experienced clinician, but developing a machine automated segmentation process is complicated because of the existence of characteristic artifacts. In this article, we present a novel end-to-end network that enables automated measurements of the fetal head circumference (HC) and fetal abdomen circumference (AC) to be made from 2-dimensional (2D) ultrasound images during each pregnancy trimester. These measurements are necessary, because the HC and AC are used to predict gestational age and to monitor fetal growth. Automated HC and AC assessments are valuable for providing independent and objective results and are particularly useful for application in developing countries where trained sonographers are in short supply. We propose a scale attention expanding network that builds a feature pyramid inside the network, and the intermediate result of each scale is then concatenated to the feature with a fusion scheme for the next layer. Furthermore, a scale attention module is proposed for selecting the most useful scale and for reducing scale noise. To optimize the network, a deep supervision method based on boundary attention is employed. Results of experiments show that the scale attention expanding network obtained an absolute difference, Hausdorff distance, and dice similarity coefficient of 1.81 ± 1.69%, 1.22 ± 0.77%, and 97.94%, respectively, which were top results in the HC18 data set, and respective results on the abdomen set were 2.23 ± 2.38%, 0.42 ± 0.56%, and 98.04%. The experiments conducted demonstrate that our method provides a superior performance to existing fetal ultrasound segmentation methods.

How to Perform Intra-Operative Contrast-Enhanced Ultrasound of the Brain-A WFUMB Position Paper

Intra-operative ultrasound has become a relevant imaging modality in neurosurgical procedures. While B-mode, with its intrinsic limitations, is still considered the primary ultrasound modality, intra-operative contrast-enhanced ultrasound (ioCEUS) has more recently emerged as a powerful tool in neurosurgery. Though still not used on a large scale, ioCEUS has proven its utility in defining tumor boundaries, identifying lesion vascular supply and mapping neurovascular architecture. Here we propose a step-by-step procedure for performing ioCEUS analysis of the brain, highlighting its neurosurgical applications. Moreover, we provide practical advice on the use of ultrasound contrast agents and review technical ultrasound parameters influencing ioCEUS imaging.

Artificial Intelligence Pulse Coupled Neural Network Algorithm in the Diagnosis and Treatment of Severe Sepsis Complicated with Acute Kidney Injury under Ultrasound Image

The objective of this study was to explore the diagnosis of severe sepsis complicated with acute kidney injury (AKI) by ultrasonic image information based on the artificial intelligence pulse coupled neural network (PCNN) algorithm. In this study, an algorithm of ultrasonic image information enhancement based on the artificial intelligence PCNN was constructed and compared with the histogram equalization algorithm and linear transformation algorithm. After that, it was applied to the ultrasonic image diagnosis of 20 cases of severe sepsis combined with AKI in hospital. The condition of each patient was diagnosed by ultrasound image performance, change of renal resistance index (RRI), ultrasound score, and receiver operator characteristic curve (ROC) analysis. It was found that the histogram distribution of this algorithm was relatively uniform, and the information of each gray level was obviously retained and enhanced, which had the best effect in this algorithm; there was a marked individual difference in the values of RRI. Overall, the values of RRI showed a slight upward trend after admission to the intensive care unit (ICU). The RRI was taken as the dependent variable, time as the fixed-effect model, and patients as the random effect; the parameter value of time was between 0.012 and 0.015, p=0.000 < 0.05. Besides, there was no huge difference in the ultrasonic score among different time measurements (t = 1.348 and p=0.128 > 0.05). The area under the ROC curve of the RRI for the diagnosis of AKI at the 2nd day, 4th day, and 6th day was 0.758, 0.841, and 0.856, respectively, which was all greater than 0.5 (p < 0.05). In conclusion, the proposed algorithm in this study could significantly enhance the amount of information in ultrasound images. In addition, the change of RRI values measured by ultrasound images based on the artificial intelligence PCNN was associated with AKI.

Colored Doppler Ultrasound Diagnosis and Pathological Analysis of Superficial Organ and Vascular Diseases

This paper proposes a fully digital signal processing scheme for ultrasonic Doppler endoscope imaging. 200 patients with superficial tissue lumps were randomly divided into two groups: the control group and the experimental group. These two groups used conventional ultrasound examination and colored Doppler ultrasound imaging technology, respectively, to observe and compare the test method and the surgical pathological examination results. Compared with the results of the two groups, the diagnostic compliance rate of the patients in the experimental group was 99.0% significantly higher than the diagnostic compliance rate of 86.0%. At the same time, 300 patients with surgery and pathologically confirmed superficial organ lesions were selected in the hospital, and all patients were diagnosed by ultrasound to observe the diagnosis. The clinical effects of colored Doppler ultrasound to diagnose vascular lesions in the lower extremities of diabetes were discussed. The rate of arteriosclerosis in the lower extremities of the observation group was 92.32%. The more than 50% vascular stenosis rate was 45.16%. The vascular blocking rate was 16. 13% and thrombosis rate 6.45% were significantly higher than the control group 12.90%, 8.06%, 0.00%, 0.00%. In the diagnosis of superficial tissue lesions, the resolution of colored Doppler ultrasound imaging technology is relatively high, which can significantly improve the clinical diagnosis rate and has clinical application value.

Application of Contrast-Enhanced Sonography on the Diagnosis of Acute and Chronic Rejection After Renal Transplantation

To test the reliability of CEUS on the diagnosis of acute (AR) or chronic rejection (CR) after renal transplantation, patients who received renal transplantation in our center from January 2011 and December 2015 were retrospectively included in the current study. All the included patients underwent contrast-enhanced ultrasonography tests. Two regions of interests were chosen to carry out time-intensity curves (TICs). The main indexes include time indexes, intensity indexes, and difference indexes. Separation of TIC1 and TIC2 was evaluated by the authors. Results revealed that time to peak 1 (TTP-1), TTP-2, absolute time to peak 1 (ATTP-1), and ATTP-2 in the CR group were significantly later than those in the graft function stable group. Peak intensity 2 is smaller in the AR group than that in the GFS group, velocity of intensity ascending 2 is slower in the CR group than that in the GFS group, terminal intensity 1 (TI-1) and TI-2 are lower in the CR group than those in the GFS group, and Vd-1 is faster in the CR group than that in the GFS group (P < 0.05). Those results indicated that contrast-enhanced ultrasonography test can satisfactorily reflect the microcirculation of transplanted kidney and can be used to assist in the early diagnosis of graft rejection.

A cross-sectional study of 502 patients found a diffuse hyperechoic kidney medulla pattern in patients with severe gout

We have previously shown that ultrasonography can detect hyperechogenic crystal deposits in the kidney medulla of patients with gout. In this cross-sectional study we investigated the frequency and clinical correlates of hyperechogenic kidney medulla in 502 consecutive primary consultants for gout (ACR/EULAR criteria) at the Vien Gut medical center in Ho Chi Minh City, Vietnam. None of these patients received urate-lowering drugs. Kidney medulla echogenicity on B-mode ultrasonography was compared to that of the kidney cortex. Overall, 36% patients showed a hyperechoic pattern of Malpighi pyramids. On univariate analysis, the pattern was significantly associated with age, estimated gout duration, steroid-dependency, clinical tophi, urate arthropathy, double contour thickness at the scanned joints, coronary heart disease, arterial hypertension, hyperuricemia, proteinuria, leukocyturia, and decreased estimated glomerular filtration rate. On multivariable analysis, the hyperechoic pattern was associated with estimated disease duration, clinical tophi, urate arthropathy, double contour thickness and decreased estimated glomerular filtration rate. No hyperechoic pattern was observed in 515 consecutive consultants without gout. Thus, hyperechoic kidney medulla was frequently demonstrated in Vietnamese patients with tophaceous gout and associated with features of tubulointerstitial nephritis. This finding revives the hypothesis of microcrystalline nephropathy of gout, predominantly seen in untreated gouty patients, which could be an important target for urate-lowering therapy.