Medical Renal Disease Research Articles

Smartphone-based machine learning model for real-time assessment of medical kidney biopsy

BackgroundKidney biopsy is the gold-standard for diagnosing medical renal diseases, but the accuracy of the diagnosis greatly depends on the quality of the biopsy specimen, particularly the amount of renal cortex obtained. Inadequate biopsies, characterized by insufficient cortex or predominant medulla, can lead to inconclusive or incorrect diagnoses, and repeat biopsy. Unfortunately, there has been a concerning increase in the rate of inadequate kidney biopsies, and not all medical centers have access to trained professionals who can assess biopsy adequacy in real time. In response to this challenge, we aimed to develop a machine learning model capable of assessing the percentage cortex of each biopsy pass using smartphone images of the kidney biopsy tissue at the time of biopsy. Methods747 kidney biopsy cores and corresponding smartphone macro images were collected from five unused deceased donor kidneys. Each core was imaged, formalin-fixed, sectioned, and stained with Periodic acid–Schiff (PAS) to determine cortex percentage. The fresh unfixed core images were captured using the macro camera on an iPhone 13 Pro. Two experienced renal pathologists independently reviewed the PAS-stained sections to determine the cortex percentage. For the purpose of this study, the biopsies with less than 30% cortex were labeled as inadequate, while those with 30% or more cortex were classified as adequate. The dataset was divided into training (n=643), validation (n=30), and test (n=74) sets. Preprocessing steps involved converting High-Efficiency Image Container iPhone format images to JPEG, normalization, and renal tissue segmentation using a U-Net deep learning model. Subsequently, a classification deep learning model was trained on the renal tissue region of interest and corresponding class label. ResultsThe deep learning model achieved an accuracy of 85% on the training data. On the independent test dataset, the model exhibited an accuracy of 81%. For inadequate samples in the test dataset, the model showed a sensitivity of 71%, suggesting its capability to identify cases with inadequate cortical representation. The area under the receiver-operating curve (AUC-ROC) on the test dataset was 0.80. ConclusionWe successfully developed and tested a machine learning model for classifying smartphone images of kidney biopsies as either adequate or inadequate, based on the amount of cortex determined by expert renal pathologists. The model's promising results suggest its potential as a smartphone application to assist real-time assessment of kidney biopsy tissue, particularly in settings with limited access to trained personnel. Further refinements and validations are warranted to optimize the model's performance.

A Study Assessing the Role of Renal Grayscale Ultrasonography and Flowmetry in Correlation With Renal Function Tests Across Various Renal Diseases.

Background Renal insufficiency, a critical concern in native and transplant kidneys, necessitates effective screening modalities for evaluation and management. Grayscale sonography has been a cornerstone in renal diagnostics, providing basic anatomical insights such as renal length, cortical thickness, and collecting system dilatation. Despite technological advancements, its impact on the differential diagnosis or management of renal disease remains limited, often showing normal findings in the presence of severe renal dysfunction. On the other hand, Doppler sonography, particularly the Doppler resistive index (RI), has shown potential in enhancing the assessment of renal dysfunction by quantifying alterations in renal blood flow and correlating with various renal pathologies and prognoses. Thus, this study aims to assess and compare the sensitivity of transabdominal and Doppler sonography as a diagnostic modality to evaluate medical renal diseases with altered renal function tests (RFTs). Methodology Participants included patients visiting the ultrasonography (USG)room at our hospital for USG of the kidneys, ureters, and bladder (USG KUB) and USG of the whole abdomen(USG W/A) with altered RFTs. Each underwent renal grayscale USG and RImeasurement, alongside standard RFTs, aiming to investigate the relationship between USG and RI findings and RFT outcomes to assess their predictive accuracy for renal function. Renal grayscale USG assessed parameters including renal dimensions, echogenicity, corticomedullary differentiation, and RI. Data management and charting were conducted with Microsoft Excel 2021 and Microsoft Word 2021. IBM SPSS Statistics for Windows, Version 24 (IBM Corp.,Armonk, NY) was utilized for data analysis. The analysis of variance (ANOVA) test examined relationships between renal parameters and RI across diagnostic groups. Furthermore, the chi-square test evaluated associations of renal ultrasound findings with RFTs and their significance. Results The study analyzed 93 patients with altered RFTs. Chronic kidney disease (CKD) affected 68 patients, primarily males in their fifth and sixth decades, showing reduced renal dimensions, increased cortical echogenicity, and elevated Doppler RI mean (RIm) with 83% sensitivity. Acute kidney injury (AKI) was found in 12 patients, mainly in their fourth decade, displaying increased renal parameters and elevated RIm with 75% sensitivity. Glomerular diseases, including nephrotic syndrome (NS) and nephritic syndrome (NeS), occurred in 9 patients, predominantly males in their fourth decade, with heightened renal cortical echogenicity and elevated RIm with 55.5% sensitivity. Lupus nephritis (LN) was detected in 4 female patients, despite normal renal parameters, showing elevated serum creatinine levels. Conclusions Doppler assessment of renal vascular waveforms effectively identifies chronic renal changes, aiding in the diagnosis of altered RFTs and guiding prognosis. While it detects typical changes like decreased size and parenchymal atrophy, it may not be as indicative of diabetic nephropathy. Key ultrasound indicators such as changes in echotexture and size, along with associated findings like ascites and effusions, help recognize altered renal function and minimize unnecessary interventions.

Hypertension: An Important But Reversible Cause of Systolic Dysfunction in a Cohort of Pediatric Patients.

Cardiac dysfunction due to hypertension (CDHTN) in pediatrics is not well described. We aimed to describe the presentation and outcomes of pediatric CDHTN and identify clinical features associated with resolution of dysfunction. A single-center retrospective cohort study of patients ≤ 21years with CDHTN from January 2005-September 2020 was performed. Patients with systolic dysfunction without another cause, blood pressure > 95th percentile, and physician judgment that dysfunction was secondary to hypertension were included. Demographics, clinical characteristics, echocardiographic findings, and outcomes were examined using Fisher's exact and Mann-Whitney U tests. Multiple correspondence analysis was used to explore the relationship of resolution of dysfunction to clinical features. Thirty-four patients were analyzed at a median age of 10.9 (IQR 0.3-16.9) years. Patients were divided into groups < 1year (n = 12) and ≥ 1year (n = 22). Causes of hypertension were varied by age, with renovascular disease most common in infants (42%) and medical renal disease most common in older patients (77%). Echocardiography demonstrated mild LV dilation (median LV end-diastolic z-score 2.6) and mild LV hypertrophy (median LV mass z-score 2.4). Most patients (81%) had resolution of dysfunction, particularly infants (92%). One patient died and one patient was listed for heart transplant. None required mechanical circulatory support (MCS). No clinical features were statistically associated with resolution of dysfunction. Hypertension is an important but reversible cause of systolic dysfunction in children. Patients are likely to recover with low mortality and low utilization of MCS or transplantation. Further studies are needed to confirm features associated with resolution of dysfunction.

An International Survey of Genitourinary and Renal Pathologists Regarding Evaluation of the Non-Neoplastic Parenchyma in Kidney Cancer Specimens.

Increasing survivorship in kidney cancer patients has shifted treatment strategies to optimize renal function preservation. In 2010, the College of American Pathologists (CAP) updated their synoptic reporting guidelines for tumor nephrectomies to require evaluation of the nonneoplastic kidney parenchyma. We conducted this study to understand current practice behaviors regarding the evaluation of the nonneoplastic kidney parenchyma in tumor nephrectomy specimens. We emailed a 14-item multiple-choice survey to members of the Renal Pathology Society and Genitourinary Pathology Society. We also emailed a 12-item survey to program and associate program directors of American pathology residencies to assess the current state of renal pathology education. Ninety-eight genitourinary and 104 renal pathologists responded to the survey on the nonneoplastic kidney parenchyma. Ninety-five percent of respondents who examine tumor nephrectomies reported evaluating the nonneoplastic kidney parenchyma. Seventy-five percent of genitourinary pathologists and 67% of renal pathologists use synoptic reporting, and 81% use the CAP protocol. Thirty-nine percent of respondents report always contacting the clinician when they find evidence of medical renal disease. Forty-two program leaders responded to our renal pathology education survey, and 64% of them have a mandatory renal pathology rotation that on average lasts about 2 to 4 weeks. The majority of pathologists examine the nonneoplastic kidney parenchyma of tumor nephrectomies and frequently report incidences of new medical renal disease directly to clinicians, but there remains room for improvement and educational gaps during residency training. Further efforts to standardize both this evaluation and renal pathology education will improve patient care.

Renal biopsy - indication and its implications in management of children admitted at a tertiary care hospital, Mangalore

Background: Percutaneous renal biopsy is an established diagnostic tool for identification of renal pathology required for diagnosis, treatment, and prognostication. The present study was conducted to know the common indications and histopathological findings of renal biopsy, impact of biopsy report on treatment, and complications of procedure. Methods: This was a retrospective observational study conducted in the paediatric ward of a tertiary care level hospital. Indications of renal biopsy as suggested by medical records were noted down. Any treatment changes happened after final histopathological report were recorded. Statistical analysis was made using statistical package for the social sciences (SPSS) version 20.0 (IBM, NY). Results: The mean age of patients at which biopsy was done was 9.83±5.31 years. Most common indications of renal biopsy were nephritic onset nephrotic syndrome (34.8%), steroid-resistant nephrotic syndrome (21.7%), steroid-dependent nephrotic syndrome requiring calcineurin inhibitors (CNI) (17.4%), lupus nephritis (8.7%), nephrotic syndrome with later age of onset (8.7%), acute kidney injury (AKI) stage 3 (4.3%) and for evidence of calcineurin inhibitor toxicity (4.3%). Focal segmental glomerulosclerosis (26.1%), minimal change disease (21.7%) and membranoproliferative glomerulonephrosis (17.4%) were the most common histopathological findings. Conclusions: This study reiterates the fact that renal biopsy is one of the decisive and diagnostic procedures and has good prognostic value in further management of medical renal disease.

Nontargeted Native Renal Biopsy Adequacy: Preintervention Data From a Province-Wide, Multicentre, and Interdepartmental Audit.

Nontargeted renal biopsy is essential to diagnosis, classification, and prognostication of medical renal disease. Inadequate biopsies delay diagnosis, expose the patient to repeated biopsy, and increase costs. The purpose of this project is to characterize nontargeted renal biopsy specimen adequacy and identify areas for improvement. This project was designed as a clinical audit of specimen adequacy rates of nontargeted renal biopsies from 13 hospitals, as well as a questionnaire of radiology and pathology department staff regarding current practices surrounding renal biopsies. Retrospective analysis of 2188 adult native renal biopsies was performed from January 1, 2018, to September 9, 2021, across 13 hospitals. Adult patients with medical renal disease undergoing a nontargeted renal biopsy were included. Retrospective analysis of 2188 adult native renal biopsies was performed from January 1, 2018, to September 9, 2021, across 13 hospitals. Adequacy was divided into 4 categories based on number of glomeruli received: ideally adequate (≥25 glomeruli), minimally adequate (15-24), suboptimal (<15 and diagnosis rendered), and inadequate (<15 and no diagnosis rendered). Two targets were chosen; target 1, to achieve a combined suboptimal and inadequate rate ≤ 10%, and target 2, to attain an ideally adequate rate ≥80%. Radiology department heads in the province were surveyed on biopsy equipment, technique, technologist support, and feasibility of possible interventions to enhance biopsy adequacy. Pathology department staff were surveyed on their education and experience. Adequacy was as follows: ideally adequate 64.7%, minimally adequate 26.0%, suboptimal 7.9%, and inadequate 1.4%. The province (and 8/13 hospitals) met target 1 for native biopsies (9.3%). Two hospitals achieved target 2 for native biopsies. A key finding was that the 2 hospitals with the lowest target 1 scores did not have a technologist present at biopsy. Survey data was used to assess biopsy technique at each hospital, and specific technique for each biopsy was not recorded. As such, a multivariate statistical analysis of specimen adequacy rates was not feasible. Data on complications was not collected. Preintervention the province was at target for limiting inadequate and suboptimal native biopsies. There was a substantial shortfall in the ideally adequate rate from the proposed target. Using insight from survey data, interventions with the greatest expected impact were identified and those that are feasible given limited resources will be implemented to improve sample adequacy. Not registered.

Paraneoplastic Nephropathy with Peculiar Immunofluorescence Pattern: Report of a Rare Case

Abstract Introduction/Objective Hematolymphoid neoplasms are commonly associated with medical renal disease; however, association of renal cell carcinoma and nephrotic/nephritic syndrome is exceedingly rare. Paraneoplastic nephropathy in setting of renal cell carcinoma can manifest as membranous nephropathy, IgA nephropathy, or minimal change disease. The purpose of this report is to describe a rare case of clear cell renal cell carcinoma with associated membranous nephropathy with concurrent glomerular IgG and IgA deposition. Methods/Case Report A 68-year-old male presented with a penile mass. Diagnostic work up reveled an 11cm renal mass. Urinalysis demonstrated nephrotic range proteinuria (&amp;gt;5 g/d). Subsequently, the patient underwent nephrectomy and penectomy. Pathologic evaluation showed clear cell renal carcinoma with sarcomatoid component and metastasis to penis. Nonneoplastic kidney workup revealed membranous glomerulopathy, with 3+ granular IgG predominantly within glomerular capillaries and 2+ IgA and 1+ C3 in a similar pattern. Electron microscopy demonstrated numerous subepithelial and intramembranous immune deposits, and few small mesangial deposits. Concurrent membranous and IgA nephropathy has been reported, but the IgA in that case is typically mesangial. The peculiar pattern of IgG and IgA deposition in this case can be seen with membranous nephropathy secondary to lupus or neoplasia. Lupus was excluded based on patient’s history, serology, and absence of significant C1q staining. Therefore, the findings were consistent with membranous glomerulopathy secondary to patient’s cancer. Patient’s proteinuria improved after nephrectomy. He is alive and disease-free 10months after nephrectomy, with proteinuria in 0.1-0.6 g/d range. Results (if a Case Study enter NA) NA Conclusion This case highlights the importance of thorough evaluation of non-neoplastic kidney in nephrectomy specimens for cancer, thus guiding the type of surgical intervention. Non-orthodox presentation of immunoglobulin deposition may be the herald of neoplasia in select cases.

CAIX Immunostaining in Non-neoplastic Renal Diseases.

Carbonic anhydrase 9 (CAIX) is a transmembrane metalloenzyme that regulates cellular adhesion, proliferation, and intra/extracellular pH. It is expressed primarily through a hypoxia-inducible factor 1 (HIF-1)-dependent mechanism. Its over-expression is closely related to somatic mutations in the Von Hippel-Lindau (VHL) gene. Studies have shown that it is over-expressed in renal cell carcinoma. In this study, we aimed to assess the value of CAIX immunostaining as an ancillary diagnostic tool in renal malignancies and medical renal diseases. Slides of kidney tumors and medical kidney diseases were selected to evaluate CAIX expression. Intensity and staining patterns of CAIX were independently assessed by two pathologists. Our results showed strong and diffuse box-like membranous staining pattern in the majority of the clear cell renal cell carcinoma (ccRCC) cases (47/59 cases; 94%). A strong, diffuse cup-shaped staining pattern was observed in clear cell papillary RCC. Variable positivity was observed in other RCC (renal cell carcinoma) subtypes. In non-neoplastic renal conditions, the majority of the cases were negative for CAIX, and only a few cases demonstrated patchy non-specific staining. Of note, a single case of transplanted kidney biopsy taken because of delayed graft function showed a focal area of dilated tubules lined by cells with clear cytoplasm and enlarged nuclei with prominent nucleoli. This area showed diffuse membranous staining for CAIX. Two cases of end-stage renal disease showed a focal circumferential membranous staining pattern for CAIX in dilated tubules. The CAIX immunoreactivity observed in these three cases could be indicative of an early-stage renal cell neoplasm and warrants further investigation.

ODP106 Mystery of the Calcium: A Case of Exclusive Cutaneous Sarcoidosis presenting with Symptomatic Hypercalcemia

Abstract The skin is the second most involved organ after the lung in sarcoidosis. It could be an early manifestation that may progress to systemic disease later. Exclusive cutaneous disease is more frequently seen in females. Specific lesions include erythema nodosum, skin plaques, subcutaneous nodules, maculopapular rashes, lupus pernio, scar lesions, and psoriasiform lesions. Most with cutaneous sarcoidosis need no treatment unless there is associated cosmetic disfigurement. We present a unique case of cutaneous sarcoidosis presenting with symptomatic hypercalcemia without systemic disease. A 75-year-old African American female was admitted with generalized weakness. She had no other symptoms. On arrival, she was bradycardic with other normal vitals. Physical examination was normal. EKG showed sinus bradycardia with RBBB. She was found to have AKI with creatinine of 4.3 mg/dL (0.6-1.3 mg/dL) and a corrected calcium of 12.2 mg/dL (8.6-10.2 mg/dL). TSH was 4.64 uIU/mL (0.35-5.50 uIU/mL). Chest X-ray showed no abnormalities. Renal ultrasound revealed bilateral medical renal disease, with several non-obstructing calculi in the right kidney. The patient was managed with intravenous fluids. Her creatinine improved to 3.1 mg/dL; however, the calcium remained elevated at 11.8 mg/dL. PTH was 31 pg/mL (12-88 pg/mL) and urine 24-hr calcium was elevated at 470 mg (35-250 mg). 25-OH vitamin D level was 40 ng/mL (30-100 ng/mL). With no response to intravenous hydration, IV bisphosphonates were initiated. Despite that, her calcium remained at 11.9 mg/dL. On obtaining a more detailed history, it was revealed that a skin punch biopsy performed six years prior showed sarcoid granulomatous dermatitis. The 1, 25 dihydroxy vitamin D was 93 pg/mL (20-79 pg/mL). The ACE level was high at 64 U/L (8-52 U/L). CT chest showed no evidence of granulomatous disease, including the absence of hilar adenopathy. The patient was started on prednisone 20 mg/day. Her calcium trended down to 10.7 mg/dL over the next three days. Although cutaneous sarcoidosis may not be life-threatening, it may have substantial psychological and social impacts. Hypercalcemia is a high prevailing complication of systemic sarcoidosis. It occurs due to the uncontrolled synthesis of 1,25-OH D3 by macrophages in the sarcoid granulomata. As a result, there is increased calcium absorption in the intestine and calcium resorption in the bone. Glucocorticosteroids act by inhibiting the 1alpha-hydroxylase activity of macrophages. Prednisone 20 to 40 mg/day followed by a taper is the recommended dose. Other medications that may be used include antimalarials, thalidomide, methotrexate, and other immunomodulatory agents. Hypercalcemia in a patient with cutaneous sarcoidosis and no pulmonary involvement is a rare presentation. It is essential to recognize that long-term follow-up is advised for those with cutaneous sarcoidosis, as some may develop systemic involvement subsequently. Presentation: No date and time listed

Clinical Outcomes Following Definitive 3D Image-Guided HDR Intracavitary Brachytherapy for Medically Inoperable Endometrial Cancer

<h3>Purpose/Objective(s)</h3> Endometrial cancer (EC) is the most common gynecologic malignancy in the U.S. Brachytherapy alone or in combination with external beam radiation therapy (EBRT) is considered an alternative definitive treatment for women who are not surgical candidates, though limited data exists for outcomes with modern 3D image-guided brachytherapy. As the U.S. population ages and rates of obesity and other comorbidities rise, more women may require definitive radiation therapy. In this study, we report outcomes for a large cohort of patients treated with intrauterine brachytherapy with 3D CT-guided planning. <h3>Materials/Methods</h3> Retrospective review identified 59 women with EC who received high dose rate (HDR) intrauterine brachytherapy with dual or triple tandem applicators with definitive intent, alone or in combination with EBRT, between 2009-2020. All patients underwent endometrial biopsy and 92% had pretreatment diagnostic CT and/or MRI imaging. 3D CT-guided brachytherapy planning was done using planning software. Local failure-free survival (LFFS), disease-free (DFS), and overall survival (OS) estimates were calculated by Kaplan-Meier method. Median follow-up was 44 months (interquartile range [IQR], 17-88). <h3>Results</h3> Median patient age was 68 years (range, 37-87). Patients had atypical complex hyperplasia (15%), or clinical stage I (76%), II (5%), or III (3%) EC. Patients were ineligible for surgery due to medical comorbidities, including obesity (97% of patients), pulmonary disease (36%), cardiovascular disease (41%), renal disease (9%), or complicated prior surgical history (9%). Median BMI was 45.7 kg/m² (range, 17.2-79.7), and 64% of patients met criteria for severe obesity (≥40 kg/m²). Brachytherapy dose delivered ranged from 8.5Gy in 1 fraction to 36.5Gy in 5 fractions. Among patients receiving brachytherapy alone, 83% were treated with 34Gy in 4 fractions. 20% of patients underwent EBRT immediately prior to or following brachytherapy and received lower doses of brachytherapy. Median coverage of the uterus CTV V100 = 92% (range, 65%-99%). 5-year LFFS, DFS, and OS rates were 91%, 82%, and 75%, respectively. Median time to any failure was 15 months (IQR, 10-26). Among 59 patients, 4 failed locally, 3 failed in the peritoneum, and 2 failed both locoregionally and distally. Two of 4 patients who failed locally were successfully salvaged with surgery. Five patients died of EC. Ten patients (17%) had perforation of the uterus with applicator placement. Antibiotics were not given prophylactically and no patients developed bacterial peritonitis or other infectious complication. There was no correlation between perforation of the uterus at the time of brachytherapy and peritoneal spread of EC. <h3>Conclusion</h3> Outcomes following definitive 3D image-guided brachytherapy were excellent, with 5-year LFFS of 91% and 5-year DFS of 82%. Patients rarely died of EC. Our data supports the use of 3D brachytherapy as definitive therapy for patients who are not candidates for surgery.

Ultrasound Versus Computed Tomography-Guided Native Parenchymal Kidney Biopsies for Hospitalized Patients: Comparison of Clinical Outcomes and Complications.

Percutaneous native kidney biopsies performed with ultrasound (US) or computed tomography (CT) guidance are important in the workup of medical renal disease, with modality choice often dependent on the performing institution, with various complication rates reported. We compared the complication rates and types of complication of US- versus CT-guided native parenchymal renal biopsy among hospitalized patients. One hundred five consecutive inpatient US- and CT-guided native parenchymal renal biopsies performed by radiologists at a tertiary care academic center between 2006 and 2020 were reviewed retrospectively. Complication rates of biopsy were calculated and compared between the 2 modalities. Comparisons with regard to types of complications were made using the Society of Interventional Radiology grading scale, American Society of Anesthesiologists score, and other clinical data. One hundred five hospitalized adult patients (58 women and 47 men; average age, 53 years) underwent native parenchymal kidney biopsy during the study period. Sixty-three (60%) were CT-guided and 42 (40%) were US-guided. Complication rates between CT- versus US-guided biopsies were 40% versus 19% ( P = 0.03), respectively. There were 7 major and 18 minor complications for CT-guided biopsies and 3 major and 5 minor complications for US-guided biopsies. No statistically significant difference was found in preprocedural American Society of Anesthesiologists Classification score, international normalized ratio, platelet count, or body mass index. Computed tomography-guided native parenchymal kidney biopsy was associated with a higher overall complication rate compared with US-guided biopsy for hospitalized patients. Most complications were minor, which required no treatment or additional follow-up.

A Case of Membranous Nephropathy Hypothesized to be Associated With COVID-19 Vaccine

A 56-year-old male patient with a medical history of essential hypertension was referred to the emergency room after he was found to have a serum creatinine level of 13 mg/dL at his primary care physician’s office. The patient reported that he had developed a coronavirus disease 2019 (COVID-19)-like infection six months prior that was not confirmed. Two months later, he started to notice dyspnea on exertion and bilateral lower limb swelling and was started on furosemide. He received the first dose of the Moderna COVID-19 vaccine a month before the presentation but did not receive the second dose. Subsequently, his lower limb swelling and exertional dyspnea started worsening. He denied any new medication, dysuria, oliguria, hematuria, fever, or any other symptoms. Initial evaluation was consistent with kidney failure. Hypocalcemia and hyperphosphatemia were noted, along with medical renal disease on renal ultrasound. Eosinophils and nephrotic-range proteinuria were found in the urine. His serum phospholipase A2 receptor (PLA2R) antibodies were positive. A renal biopsy showed membranous glomerulonephritis with moderate segmental sclerosis, as well as tubulointerstitial fibrosis with neutrophils, consistent with acute interstitial nephritis. Positive staining for PLA2R in the glomerular deposits suggested primary membranous nephropathy (MN). He was treated with prednisone first, and when the kidney biopsy was conclusive for membranous glomerulopathy, he was started on rituximab. On admission, he received hemodialysis intermittently, but this was stopped a month after discharge as his renal function normalized. Recently, there have been numerous cases reported with new onset of glomerular disease after receiving the COVID-19 vaccine. Further studies of vaccinated patients are needed to determine whether the severe acute respiratory syndrome coronavirus 2 virus vaccination is associated with a higher risk of MN and to identify potential predisposing factors and mechanisms of kidney injury in patients in whom it occurs.

Hypertension: An Important but Reversible Cause of Systolic Dysfunction in Pediatrics

<h3>Purpose</h3> Cardiac dysfunction due to hypertension (CDHTN) in pediatrics is not well described. The purpose of the study is to describe the presentation and outcomes of pediatric CDHTN. <h3>Methods</h3> Patients ≤ 21 years with CDHTN between January 2005 and September 2020 at our institution were reviewed. Inclusion criteria were systolic dysfunction (shortening fraction (SF) <28% or ejection fraction <50%) without another cause of dysfunction, blood pressure (BP) >95th %ile for age and height within 3 months of diagnosis and physician judgment that dysfunction was secondary to hypertension. Demographics, clinical characteristics, echocardiographic findings and outcomes were described and examined using Chi-squared and Wilcoxon rank-sum tests. <h3>Results</h3> There were 34 patients included, with median age 10.9 (IQR 0.3-17.0) years. Due to a bimodal age distribution, patients were divided into groups <1 year (n=12) and >1 year (n=22) for outcome analysis. Causes of hypertension included medical renal disease (n=20, 59%), renovascular disease (n=6, 17%), essential (n=5, 15%), multifactorial (n=2, 6%) and medication effect (n=1, 3%). Peak systolic and diastolic BP at diagnosis was >99th %ile in 97% and 68% of patients, respectively. Echocardiography demonstrated mild LV dilation (median LV end diastolic z-score 2.6) and mild LV hypertrophy (median LV mass z-score 2.3). Patients were often symptomatic at diagnosis (n=21, 62%) and required admission (n=28, 82%), but a minority required intubation (n=9, 26%) or inotropic support (n=15, 44%). No patients received mechanical circulatory support (MCS), and only one patient was listed for transplant. Survival was high (n=33, 97%) over 3.5 (IQR 2.0-6.3) years follow up. Despite a trend toward worse function at diagnosis (SF 19% vs 23%, p=0.07), patients <1 year had shorter duration of dysfunction (12 vs 218 days, p=0.003) and better function at last follow up (SF 36% vs 29%, p=0.002). Overall, 92% of infants and 68% of older patients had resolution of systolic dysfunction. <h3>Conclusion</h3> Hypertension is an important cause of systolic dysfunction with a bimodal age distribution in children. Outcomes are favorable with low mortality and a high proportion of patients with resolution of systolic dysfunction, particularly those <1 year. Identification of hypertension as the cause of dysfunction is vital, as these patients do not often require MCS or transplantation.

Spectrum of histopathological findings in pediatric renal biopsies; a five-year single center experience in Egypt

Introduction: Medical renal diseases stand as one of the major health problems in pediatric age group considering its morbidity/mortality and the subsequent management plans. Objectives: In this manuscript, the spectrum of histopathological patterns of medical nephropathic lesions in Egyptian pediatric patients over duration of five years is reported with clinical indications. Patients and Methods: We conducted a retrospective study for analysis of our pathological reports of renal needle biopsies during the period from January 2014 until January 2019. One hundred and sixteen cases were included. Results: The most commonly encountered pediatric renal pathology was minimal change disease (27.59%), followed by congenital glomerular diseases (22.41%), focal segmental glomerulosclerosis (12.93%), and thrombotic microangiopathy (7.76%). The most common clinical indication for biopsy was nephrotic syndrome (37.07%) followed by impaired renal functions with elevated serum creatinine (21.55%). In addition, we report very rare histological findings in few cases including infantile nephropathic cystinosis, Barakat syndrome and C3 glomerulopathy. Conclusion: Minimal change disease and congenital glomerular diseases accounted for half of pediatric renal pathologies in the study population. The most common clinical indication for renal biopsy was nephrotic syndrome. Electron microscopic examination and genetic studies are mandatory for proper evaluation of pediatric nephropathies.

Role of Ultrastructural Study in the Diagnosis of Medical Renal Diseases: A Tertiary Medical Center Experience and Review of the Literature

The 20th century unfolded many mysteries regarding renal pathology with the advent of ancillary techniques such as immunofluorescence (IF) and electron microscopy (EM) studies. EM plays a major role in confirming the routine and IF findings or may uncover new and unsuspected features. The aim of the study is to elucidate the role of ultrastructural findings in patients with medical kidney diseases on whom kidney biopsy was performed at the American University of Beirut Medical Center, between November 2018 and June 2019. A total of 188 renal biopsies were examined during the study period. EM confirmed the light microscopy diagnosis in 54% of the cases while completely changed the diagnosis in 23% of the cases. In 23% of the sample, EM provided additional features and a secondary diagnosis. Our study emphasizes the important diagnostic role of EM and its significance, particularly in minimal change disease, basement membrane abnormalities, and glomerulopathies.

Late Preterm Infant With Postnatal Diagnosis of Renal Tubular Dysgenesis.

A male infant born at 34 weeks’ gestation presented with acute cardiorespiratory decompensation soon after birth followed by renal failure. Initial clinical course was complicated by ventilator requirement, bilateral pneumothoraces, and hypotension managed with multiple inotropes. Persistent renal failure with oliguria and renal ultrasound showing noncystic medical renal disease prompted further investigation. Whole-exome sequencing showed 2 pathologic mutations in the angiotensin-converting enzyme (ACE) gene, suggesting a diagnosis of renal tubular dysgenesis (RTD). Renal tubular dysgenesis is usually a fatal condition affecting the renin-angiotensin system with possible autosomal recessive inheritance. Acquired cases have been described in the setting of in utero exposure to medications such as nonsteroidal anti-inflammatory medications (NSAIDs) and ACE inhibitors. Renal tubular dysgenesis should be suspected in any neonate presenting with renal failure, refractory hypotension, ventilator requirement, hypoplastic lungs, renal ultrasound showing normal-sized echogenic noncystic kidneys with poor corticomedullary differentiation, and antenatal history significant for oligohydramnios. The overall prognosis of patients with RTD continues to improve with better ventilatory management and renal replacement therapies.

Kidney Tissue Biopsy

Kidney tissue biopsy is a commonly performed procedure which is valuable in the work-up for patients with medical renal disease and renal transplant. This article will review indications, contraindications, technique and potential complications of kidney biopsy.

The use of hemodialysis in hypercalcemic crisis secondary to primary hyperparathyroidism

Severe hypercalcemia can be either acute or decompensate from a chronic state to a medical emergency, the hypercalcemic crisis. The presence of symptoms such as altered mental status or potentially fatal ECG abnormalities demand an expeditious decrease in serum calcium levels. Standard medical therapy consists of vigorous volume replacement, calcitonin and, depending on the etiology, bisphosphonates, cinacalcet or glucocorticoids. Hypercalcemic crisis is a rare indication for urgent hemodialysis and is reserved for patients with severe symptoms, ineffective medical therapy or end stage renal disease. The use of hemodialysis in this scenario is not commonly reported. We hereby report a patient who presented with altered mental status and acute kidney injury due to a hypercalcemic crisis secondary to primary hyperparathyroidism. Treatment included urgent hemodialysis to effectively lower calcium levels.

Ultrasound Studies of COVID-19-Positive Patients and Patient Under Investigation: Pandemic Experience of Body Imaging Division at a Tertiary Medical Center.

This retrospective study shares our departmental experience of screening of ultrasound (US) requests, triaging of studies, and abbreviated US protocols implemented during the COVID-19 pandemic. For US studies requested in April and May 2020, the following data were collected: type of study, indication, COVID-19 status (positive or patient under investigation [PUI]), decision to perform study, US findings, and location of patient. A total of 196 US studies in 150 patients were included. The median age of patients was 60 years (female: 46.7% [70/150]). At the time of study request, 83 patients (55.3%) were COVID-19-positive and 67 (44.7%) were PUI, of which 8 (11.9%) tested positive after waiting for test result. The most frequently requested study was venous extremity Doppler (51%), followed by right upper quadrant (20.4%), renal (11.7%), and liver duplex (6.6%). After radiologist screening and triage of US requests, 156 studies were performed (79.6%), 15 were postponed until COVID test result (7.6%), and 40 were not performed after discussion with ordering provider (20.4%). Notably, 40.1% of studies performed on COVID-19-positive patients yielded pathological findings, most frequently deep venous thrombosis (18.1%), medical renal disease (7.6%), and gall bladder sludge (5.7%). Abbreviated US protocols were used in 29.4% of studies. In conclusion, US study screening and triage played an important role to optimize care of COVID-19 patients and PUIs.

Epidemiology of Pediatric Renal Diseases and its Histopathological Spectrum - A Single-Center Experience from India.

Pediatric renal biopsy is an uncommon event, and the spectrum of the disease is evaluated and managed mostly on the clinical grounds. Compared to adults, the indications for renal biopsy in pediatric population are very few. We reviewed the pediatric renal biopsies received at our tertiary center in Mumbai, India, over a period of six years to study the incidence of various medical renal diseases, their spectrum on histology and its correlation with electron microscopy (EM). A total of 65 pediatric renal biopsies in the age group of 0-12 years were evaluated over a period of six years. The mean age of our patients was 7.9 years, with a median of 8.8 years with a male-to-female ratio of 1.3:1. The overall most common indication for biopsy was nephrotic syndrome (NS) including steroid-resistant NS, followed by proteinuria and nephritic syndrome. Majority of the lesions included in the study were primary glomerular disease (71%) while secondary glomerular disease amounted to 18%. The spectrum of disease includes minimal-change disease (MCD) (27.7%), followed by membranoproliferative glomerulonephritis (MPGN) (15.38%), focal segmental glomerulosclerosis (FSGS) (9.23%), lupus nephritis (7.7%), hemolytic uremic syndrome (7.7%), MPGN (6.15%), advanced renal disease (6.15%), membranous glomerulonephritis (3.07%), and crescentic glomerulonephritis (3.07%). This study is an important contribution to the epidemiology of pediatric renal disease spectrum in the Indian population. We conclude that MCD is the most common pathology seen in pediatric age group, with NS as the most common indication for biopsy. There is a steady increase in the incidence of FSGS in the pediatric population with frequent relapses and an increase in the incidence of steroid resistance. However, with the use of immunofluorescence and EM, an accurate diagnosis is possible, so an early renal biopsy should be planned in nonresponding cases and at times even before starting the treatment for appropriate treatment.