Multifocal lesions in a kidney allograft.

BACKGROUND: Common complications following kidney transplant include infection, rejection, and malignancy. Multiple masses in a transplanted kidney raise suspicion for malignancy. CASE PRESENTATION: A 20-year-old female with chronic kidney disease stage 3 T presented with graft tenderness, acute kidney injury, and heterogeneous masses in her transplanted kidney visualized via ultrasound. She was inadequately treated for chlamydia 1 month prior and retested positive upon admission. Initial workup revealed anemia, hyperglycemia, hyperuricemia, and elevated lactate dehydrogenase. Magnetic resonance imaging revealed complex masses of varying sizes in the transplanted kidney. Biopsy grew Streptococcus agalactiae, informing the diagnosis of multiple perinephric abscesses. Additional evaluations for infectious etiology were unremarkable. Her perinephric abscesses resolved with several months of antibiotics. CONCLUSIONS: Even without a clear source, serious infections may develop in kidney transplant patients who otherwise have concern for malignancy. Chlamydial infections may lead to serious intra-abdominal infections in immunocompromised patients. The inadequately treated chlamydia likely led to polymicrobial ascension of the genitourinary tract that seeded the transplanted kidney. A high index of suspicion for infection is essential in immunosuppressed patients. Biopsy is crucial for a timely diagnosis.

Assessment of fluid removal using ultrasound, bioimpedance and anthropometry in pediatric dialysis: a pilot study.

BACKGROUND: Fluid overload is associated with morbidity and mortality in children receiving dialysis. Accurate clinical assessment is difficult, and using deuterium oxide (D2O) to measure total body water (TBW) is impractical. We investigated the use of ultrasound (US), bioimpedance spectroscopy (BIS), and anthropometry to assess fluid removal in children receiving maintenance hemodialysis (HD). METHODS: Participants completed US, BIS, and anthropometry immediately before and 1-2 h after HD for up to five sessions. US measured inferior vena cava (IVC) diameter, lung B-lines, muscle elastography, and dermal thickness. BIS measured the volume of extracellular (ECF) and intracellular (ICF) fluid. Anthropometry included mid-upper arm, calf and ankle circumferences, and triceps skinfold thickness. D2O was performed once pre-HD. We assessed the change in study measures pre- versus post-HD, and the correlation of change in study measures with percent change in body weight (%∆BW). We also assessed the agreement between TBW measured by BIS and D2O. RESULTS: Eight participants aged 3.4-18.5 years were enrolled. Comparison of pre- and post-HD measures showed significant decrease in IVC diameters, lung B-lines, dermal thickness, BIS %ECF, mid-upper arm circumference, ankle, and calf circumference. Repeated measures correlation showed significant relationships between %∆BW and changes in BIS ECF (rrm =0.51, 95% CI 0.04, 0.80) and calf circumference (rrm=0.80, 95% CI 0.51, 0.92). BIS TBW correlated with D2O TBW but overestimated TBW by 2.2 L (95% LOA, -4.75 to 0.42). CONCLUSION: BIS and calf circumference may be helpful to assess changes in fluid status in children receiving maintenance HD. IVC diameter, lung B-lines and dermal thickness are potential candidates for future studies.

Autoimmune Myelofibrosis in a 12-Year-old Male With Monosomy 7, Systemic Lupus Erythematous and Lupus Nephritis: A Case Report and Review of the Literature.

Complete or partial loss of chromosome 7 is a common and well-known cytogenetic abnormality associated with preleukemic myelodysplasia and myeloid leukemia but not with autoimmune myelofibrosis. Detection of this molecular change represents poor prognosis. When malignant transformation occurs, the condition tends to be chemotherapy-resistant requiring haematopoietic stem cell transplantation (HSCT) to obtain a cure. Disappearance after immunosuppressive therapy has been documented in children with hematological disorders but not in association with cyclophosphamide and systemic lupus erythematous.We present the interesting case of a 12-year-old male with monosomy 7, systemic lupus erythematous, and lupus nephritis with the resolution of the monosomy 7 and autoimmune myelofibrosis after treatment with cyclophosphamide, along with a review of the literature.

Omentectomy reduces the need for peritoneal dialysis catheter revision in children: a study from the Pediatric Nephrology Research Consortium.

BACKGROUND: There are no multi-center studies examining omentectomy and peritoneal dialysis (PD) catheter revision in the pediatric dialysis population. METHODS: We performed a retrospective study at eight centers within the Pediatric Nephrology Research Consortium (PNRC). Data review included all incident tunneled PD catheters placed between 1/1/2011 and 12/31/2016 in pediatric stage 5 chronic kidney disease (CKD 5) patients. The primary outcome was the need for catheter revision and/or replacement. Multivariable logistic regression was performed to evaluate predictors for catheter revision/replacement. RESULTS: Data from 184 children (62.5% male; median age 7.4 years) were analyzed. Omentectomy was completed in 63.6% (n = 117). Revision/replacement occurred in 34.2% (n = 63); median time to revision/replacement was 38.5 days after insertion. PD catheter revision/replacement catheter occurred in 23.9% who underwent omentectomy versus 52.2% without omentectomy (p = 0.0005). Children ≥ 6 years at the time of catheter insertion experienced fewer revisions/replacements (18.2% age ≥ 6 vs. 56.5% age < 6 years, p <0.001). After adjusting for covariates, omentectomy reduced the need for revision by 63%; revision was 3.66 times more likely in those < 6 years of age. CONCLUSIONS: This multi-center study demonstrates that omentectomy at the time of PD catheter insertion in pediatric patients is strongly associated with reduced likelihood of PD catheter revision. Omentectomy should be considered at the time of PD catheter insertion, especially in young children who are at high risk for PD catheter malfunction. A higher resolution version of the Graphical abstract is available as Supplementary information.

De novo collapsing glomerulopathy in a pediatric kidney transplant recipient with COVID-19 infection.

The negative impact of COVID-19 on adults with underlying chronic kidney disease, including kidney transplant recipients, has been well documented. Children have a less severe presentation and better prognosis compared to adults. However, little is known regarding the spectrum of COVID-19 infection in children and adolescents with underlying autoimmune disorders necessitating solid organ transplant and long-term immunosuppressive therapy. Case Report. An adolescent male developed end-stage kidney disease secondary to microscopic polyangiitis requiring a living-donor kidney transplant. Six years later, he developed antibody-mediated rejection of his kidney transplant. During his rejection treatment course, he contracted SARS-CoV-2 and developed new-onset nephrotic syndrome with severe acute kidney injury. Kidney transplant biopsy revealed de novo collapsing focal segmental glomerulosclerosis on a background of chronic active antibody mediated rejection. Immunostaining for SARS-CoV-2 on the biopsy specimen demonstrated positive staining of the proximal tubular epithelium consistent with intra-renal viral infection. Pulse corticosteroids, intravenous immunoglobulin, and temporary reduction of anti-metabolite therapy resulted in successful recovery with return of graft function back to pre-infection baseline. This case highlights the clinical conundrum of treating kidney transplant recipients with active rejection in the midst of the COVID-19 pandemic. Pediatric kidney transplant recipients can develop severe COVID-19-related kidney complications. Judicious immunosuppression modulation is necessary to balance infection and rejection risk.

Emerging monitoring technologies in kidney transplantation.

Non-invasive technologies to monitor kidney allograft health utilizing high-throughput assays of blood and urine specimens are emerging out of the research realm and slowly becoming part of everyday clinical practice. HLA epitope analysis and eplet mismatch score determination promise a more refined approach to the pre-transplant recipient-donor HLA matching that may lead to reduced rejection risk. High-resolution HLA typing and multiplex single antigen bead assays are identifying potential new offending HLA antibody subtypes. There is increasing recognition of the deleterious role non-HLA antibodies play in post-transplant outcomes. Donor-derived cell-free DNA detected by next-generation sequencing is a promising biomarker for kidney transplant rejection. Multi-omics techniques are shedding light on discrete genomic, transcriptomic, proteomic, and metabolomic signatures that correlate with and predict allograft outcomes. Over the next decade, a comprehensive approach to optimize kidney matching and monitor transplant recipients for acute and chronic graft dysfunction will likely involve a combination of those emerging technologies summarized in this review.

Kidney Outcomes and Hypertension in Survivors of Wilms Tumor: A Prospective Cohort Study.

OBJECTIVE: To assess the prevalence of therapy-related kidney outcomes in survivors of Wilms tumor (WT). STUDY DESIGN: This prospective cohort study included survivors of WT who were ≥5 years old and ≥1 year from completing therapy, excluding those with preexisting hypertension, prior dialysis, or kidney transplant. Participants completed 24-hour ambulatory blood pressure monitoring (ABPM). Abnormal blood pressure (BP) was defined as ≥90th percentile. Masked hypertension was defined as having normal office BP and abnormal ABPM findings. Urine was analyzed for kidney injury molecule-1, interleukin-18, epidermal growth factor, albumin, and creatinine. The estimated glomerular filtration rate (eGFR) was calculated using the bedside chronic kidney disease in children equation. Recent kidney ultrasound examinations and echocardiograms were reviewed for contralateral kidney size and left ventricular hypertrophy, respectively. Clinical follow-up data were collected for approximately 2 years after study enrollment. RESULTS: Thirty-two participants (median age, 13.6 years [IQR, 10.5-16.3 years]; 75% stage 3 or higher WT) were evaluated at a median of 8.7 years (IQR, 6.5-10.8 years) after therapy; 29 participants underwent unilateral radical nephrectomy, 2 bilateral partial nephrectomy, and 1 radical and contralateral partial nephrectomy. In this cohort, 72% received kidney radiotherapy and 75% received doxorubicin. Recent median eGFR was 95.6 mL/min/1.73 m2 (IQR, 84.6-114.0; 11 [34%] had an eGFR of <90 mL/min/1.73 m2). Abnormal ABPM results were found in 22 of 29 participants (76%), masked hypertension in 10 of 29 (34%), and microalbuminuria in 2 of 32 (6%). Of the 32 participants, 22 (69%) had abnormal epidermal growth factor; few had abnormal kidney injury molecule-1 or interleukin-18. Seven participants with previous unilateral nephrectomy lacked compensatory contralateral kidney hypertrophy. None had left ventricular hypertrophy. CONCLUSIONS: In survivors of WT, adverse kidney outcomes were common and should be closely monitored.

Vecuronium- and Esmolol-Induced Pseudohypernatremia Due to Drug Interference With Ion-Selective Electrodes.

OBJECTIVES: We observed that patients treated with continuous vecuronium or esmolol infusions showed elevated plasma sodium measurements when measured by the routine chemistry analyzer as part of the basic metabolic panel (Vitros 5600; Ortho Clinical Diagnostics, Raritan, NJ), but not by blood gas analyzers (RAPIDLab 1265; Siemens, Tarrytown, NY). Both instruments use direct ion-selective electrode technology, albeit with different sodium ionophores (basic metabolic panel: methyl monensin, blood gas: glass). We questioned if the basic metabolic panel hypernatremia represents artefactual pseudohypernatremia. DESIGN: We added vecuronium bromide or esmolol hydrochloric acid to pooled plasma samples and compared sodium values measured by both methodologies. We queried sodium results from the electronic medical records of patients admitted at Children's Hospital of Philadelphia from 2016 to 2018 and received vecuronium and/or esmolol infusion treatment during their admissions. SETTING: PICU of a quaternary, free-standing children's hospital. PATIENTS: Children admitted to the hospital who received vecuronium and/or esmolol infusion. MEASUREMENTS AND MAIN RESULTS: Sodium was measured in pooled plasma samples by basic metabolic panel and blood gas methodologies after adding vecuronium bromide or esmolol hydrochloric acid, leading to a dose-response increase in basic metabolic panel sodium measurements. A repeated measures regression analysis of our electronic medical records showed that the vecuronium dose predicted the Δ sodium (basic metabolic panel-blood gas) sodium within 12 hours of the vecuronium administration (p < 0.0018). Esmolol showed a similar trend (p = 0.13). This occurred primarily in central line samples with continuous vecuronium or esmolol infusions. CONCLUSIONS: Vecuronium and esmolol can falsely elevate direct ion-selective electrode sodium measurements on Vitros chemistry analyzers. Unexpectedly high sodium measurements in patients receiving vecuronium and/or esmolol infusions should be further investigated with an alternate sample type (i.e., peripheral blood) or measurement methodology (i.e., blood gas) to guide treatment decisions.

Update on Dent Disease.

Dent disease is an X-linked form of chronic kidney disease characterized by hypercalciuria, low molecular weight proteinuria, nephrocalcinosis, and proximal tubular dysfunction. Clinical presentation is highly variable. Male patients may present with early-onset rickets, recurrent nephrolithiasis, or insidiously with asymptomatic proteinuria or chronic kidney disease. Mutations in both the CLCN5 and OCRL1 genes have been associated with the Dent phenotype and are now classified as Dent-1 and Dent-2, respectively. This article describes the clinical presentation, laboratory evaluation, genetics, pathophysiology, management, and future therapies of Dent disease.