Safety and Efficacy of Very Early Conversion to Belatacept in Pediatric Kidney Transplantation with Transplant-Associated Thrombotic Microangiopathy: Case Study and Review of Literature.

The inhibition of co-stimulation during T-cell activation has been shown to provide effective immunosuppression in kidney transplantation (KT). Hence, the conversion from calcineurin inhibitor (CNI) to belatacept is emerging as a potential alternate maintenance immunosuppressive therapy in those with transplant-associated thrombotic microangiopathy (TA-TMA) or in the prevention of TA-TMA. We present a 17-year-old male who presented with biopsy-proven CNI-associated TA-TMA immediately post-KT. The administration of eculizumab led to the reversal of TMA. Tacrolimus was converted to belatacept with excellent efficacy and safety during a short-term follow-up of one year. Further larger controlled studies are required to demonstrate the efficacy of this approach in children who present with early-onset TMA post-KT.

Efficacy and Safety of Eculizumab in Enteroaggregative E. coli Associated Hemolytic Uremic Syndrome.

BACKGROUND: Hemolytic uremic syndrome (HUS) may present atypically without the full triad of classical HUS. Eculizumab has been shown to be efficacious in complement-mediated atypical HUS and some cases of Shiga-toxin (ST) associated HUS. We report the utility of eculizumab in enteroaggregative E. coli (EAEC) associated HUS. CASE SUMMARY: A female toddler presented with hemolytic anemia, oliguric acute kidney injury (AKI) without thrombocytopenia, and peripheral schistocytes. The stool examination for ST was negative but positive for EAEC. She required several hemodialysis sessions and received one dosage of eculizumab with rapid reversal of AKI and hemolytic markers. A kidney biopsy revealed acute tubular injury and segmental glomerular basement membrane splitting. Genetic testing was negative for complement mutations or deficiencies. A follow-up six months later showed persistently normal renal function and hematological markers. CONCLUSION: The clinical and histological manifestations of non-ST-associated diarrheal HUS and the role of eculizumab in this condition warrant future larger studies.

Efficacy and safety of local candida immunotherapy in recalcitrant warts in pediatric kidney transplantation: A case report.

BACKGROUND: Warts are common in recipients of kidney transplantation (KT). Resistant warts which are not amenable to conventional therapies may lead to significant mor bidity. Limited data exists on safety and efficacy of local immunotherapy among immunocompromised KT recipients. CASE SUMMARY: We report a seven-year-old child who presented with recalcitrant plantar per iungual warts in the early KT period. Immunosuppression consisted of tacrolimus, mycophenolate and steroid. Due to failure of conventional anti-wart therapies, he was treated with two sessions of intralesional (IL) candida immunotherapy along with liquid nitrogen cryotherapy leading to complete resolution of the warts. Interestingly, de novo BK viremia was seen about three weeks following the last candida immunotherapy. This required reduction of immu nosuppression and other anti-BK viral therapies. Allograft function remained stable but there were donor specific antibodies detected. There also was elevated level of plasma donor derived cell-free DNA. A pneumocystis jirovecii pneumonia occurred ten months following completion of immunotherapy that was successfully treated with trimethoprim-sulfamethoxazole. During this ten-month follow-up period, there have been no recurrence of warts, and transplant kidney function has remained stable. CONCLUSION: Stimulation of cell-mediated immunity against the human papilloma virus induced by the IL candida immunotherapy is thought to be a cause for wart resolution. With this therapy, whether it is necessary to augment the immunosuppression to prevent rejection is unclear as that may come with a risk of infectious complications. Larger, prospective studies in pediatric KT recipients are needed to explore these important issues.

Early recurrence of focal segmental glomerulosclerosis in a kidney transplant recipient with APOL1 one risk variant.

Apolipoprotein 1 (APOL1) risk variants (G1 and G2) are associated with focal segmental glomerulosclerosis (FSGS) in patients of African ancestry. The prevalence of APOL1 two risk variants is lower in Hispanics and very rare in European and Asian populations. APOL1 two risk variants in donor kidneys is associated with recipient kidney graft loss, however the effect of recipient risk variant in the kidney transplant outcome is unclear. Here, we present a late adolescent male with FSGS and end stage renal disease with one APOL1 risk variant (G2) who had immediate recurrence of FSGS in the post-KT period. There was an excellent response to few sessions of plasmapheresis and Rituximab with no further recurrence of FSGS in the 1 year follow-up period. It needs to be seen whether the recipient APOL1 single risk variant causes increased susceptibility to kidney graft loss on a long run via recurrent or de novo pathologies.

Synthetic cannabinoid-associated acute interstitial nephritis: An emerging cause of pediatric acute kidney injury?

Synthetic cannabinoid (SCB) usage among children is a rapidly emerging public health concern in the United States. Acute kidney injury (AKI) is an uncommon manifestation of SCB usage, with acute tubular necrosis (ATN) as the predominant histology. Here we describe a 16-year-old adolescent who sustained severe non-oliguric AKI in association with SCB usage. Emesis, right flank pain, and hypertension were the presenting clinical features. There was no uveitis, skin rash, joint pains, or eosinophilia. Urinalysis showed absence of proteinuria or hematuria. Urine toxicology was negative. Renal sonogram showed bilateral echogenic kidneys. Renal biopsy demonstrated severe acute interstitial nephritis (AIN), mild tubulitis, and absence of ATN. AIN responded with pulse steroid followed by oral steroid. Renal replacement therapy was not required. Although the exact pathophysiology of SCB-associated AIN is not known, immune response elicited by the renal tubulointerstitial cells against the antigens present in the SCB is the most likely mechanism. A high index of suspicion for SCB-induced AKI is necessary in adolescents who present with AKI of unclear etiology.

Severe hypertriglyceridemia in an infant on chronic hemodialysis.

Severe hyperlipidemia is a risk factor for cardiovascular disease. Children with chronic kidney disease and end stage renal disease are at risk for development of hyperlipidemia. In this report, we describe a 7-month-old male infant with Denys-Drash syndrome who was found to have a "milky-layer" floating on the deaerator of the hemodialysis machine. Investigations showed severe hypertriglyceridemia of >1000 mg/dl. The patient had been on chronic continuous manual peritoneal dialysis until 6 months of age and recently had been switched to hemodialysis. Management included lowering of caloric intake and addition of medium chain triglyceride with reduction of the serum triglyceride levels to 300-400 mg/dl. Close monitoring of serum lipids and timely intervention is important to prevent serious complications associated with dyslipidemia. Observation of the "milky layer" in the deaerator of the hemodialysis machine may be an interesting visual clue of underlying severe hypertriglyceridemia.

Situs inversus totalis in an asymptomatic adolescent - importance of patient education: A case report.

BACKGROUND: Situs inversus totalis (SIT) may be an incidental finding in asymptomatic children. Patients may not understand the implications of this condition and the importance of relaying the diagnosis to their healthcare providers. CASE SUMMARY: We report an asymptomatic seventeen-year-old adolescent with previously-diagnosed SIT who presented for a routine well-child visit. During history taking, he denied any past medical conditions, including cardiovascular conditions. Only when physical exam revealed point of maximal impulse and heart sounds on the right side, did he convey that he had been diagnosed with SIT incidentally at age of 12 years. He was not aware of associated conditions or the potential implications of his diagnosis, nor did he realize it is pertinent medical history to be relayed to healthcare providers. Chest X-ray confirmed dextrocardia and abdominal X-ray showed right-sided stomach. Abdomen sonogram showed left-sided liver and right-sided spleen. Echocardiogram showed normal valvular structure and function. A comprehensive discussion was provided to address the patient's lack of understanding that SIT is a medical diagnosis with potential implications. CONCLUSION: While SIT is rare and mostly asymptomatic, affected patients may not comprehend the importance of the diagnosis and its potential ramifications. Recognition of the patient's lack of awareness allows the healthcare provider to educate the patient and hopefully can prevent potential medical and surgical complications.

Short-Term Outcome of Isolated Kidney Transplantation in Children with Autosomal Recessive Polycystic Kidney Disease: A Case Series and Literature Review.

Autosomal recessive polycystic kidney disease (ARPKD) is often associated with hepatobiliary disease in the form of hepatic fibrosis and/or Caroli disease. Combined liver-kidney transplantation (CLKT) is a transplant modality of choice in children with both end-stage renal disease (ESRD) and severe hepatic disease. However, there is no consensus on whether children with ARPKD-associated ESRD without severe hepatic disease can be treated with isolated kidney transplantation (KT) without the need for CLKT. We retrospectively studied the efficacy of isolated KT in children with ARPKD without severe hepatic disease, and followed the course of hepatic disease post KT. This is a single-center study of three children with ARPKD and ESRD who underwent isolated KT. None of them had severe hepatic disease at the time of KT. All children were clinically diagnosed with ARPKD in the immediate postnatal period. All had hepatic fibrosis of varying degrees and two had intrahepatic biliary duct (IHBD) dilatation. None had gastrointestinal (GI) bleed, portal hypertension or cholangitis. Two children had preemptive KT. Pre-transplant unilateral or bilateral native nephrectomy were performed for two children, and one underwent unilateral native nephrectomy at the time of KT. The median creatinine clearance at a median post-KT follow-up of 24 months was 60.3 mL/min/1.73 m2. The two-year graft and patient survival were both 100%. Post KT, all three patients continued to demonstrate evidence of hepatic fibrosis and IHBD on sonogram; however, none of them were either evaluated for or required liver transplantation given normal synthetic liver function and absence of portal hypertension or other severe hepatobiliary disease. There were no adverse events observed such as cholangitis, GI bleed, or multiorgan failure. Hence, an excellent short-term graft and patient survival was demonstrated in this study of children with ARPKD and mild to moderate hepatic disease who received isolated KT. Long-term follow-up and larger studies are important to assess the efficacy of isolated KT in this subset of children with ARPKD.

Hyperinsulinemic Hypoglycemia Due to PMM2 Mutation in Two Siblings with Autosomal Recessive Polycystic Kidney Disease.

Background: Hyperinsulinemic hypoglycemia (HH) is an important cause of persistent hypoglycemia in newborns and infants. Recently, PMM2 (phosphomannomutase 2) mutation has been associated with HH, especially in conjunction with polycystic kidney disease (PKD). PMM2 deficiency is one of the most common causes of congenital disorder of glycosylation (CDG). Renal involvement in PMM2-CDG manifests as cystic kidney disease, echogenic kidneys, nephrotic syndrome or mild proteinuria. Case Summary: Here, we describe a pair of siblings with HH associated with autosomal recessive polycystic kidney disease (ARPKD) and PMM2 mutation. Two siblings with ARPKD presented during infancy and early toddler years with severe hypoglycemia. Both had inappropriately elevated serum insulin, low ß-hydroxybutyrate, a need for a high glucose infusion rate, positive glycemic response to glucagon, positive diazoxide response and PMM2 mutation. Conclusions: Although this combination of HH and PKD was recently described in patients of European descent who also had PMM2 mutation, our report is unique given that these non-consanguineous siblings were not exclusively of European descent. PMM2 mutation leading to abnormal glycosylation and causing cystic kidneys and the alteration of insulin secretion is the most likely pathogenesis of this clinical spectrum.

Polyethylene Glycol 3350 Crystal Nephropathy in Association With Glomerular Mesangial Immunoglobin A Deposition.

Polyethylene glycol (PEG) 3350, an active ingredient of over-the-counter MiraLAX, is a commonly used laxative in children and is produced by polymerization of ethylene glycol (EG). Masked EG toxicity secondary to contamination of PEG 3350 could occur. We present a 7-year-old child with developmental delay who presented with altered mental status and acute kidney injury (AKI) following intake of generic PEG 3350 for few days prior to presentation. There was high anion gap metabolic acidosis, hypernatremia, elevated osmolar gap, lactic acidosis, and AKI. Urinalysis showed tubular proteinuria, microscopic hematuria, and calcium oxalate crystals. Prior urinalyses were normal without hematuria or proteinuria. Renal biopsy revealed evidence of mesangial dominant immunoglobulin A (IgA) and complement 3 (C3) deposits along with dense tubular deposition of calcium oxalate crystals. He subsequently developed worsening oliguric AKI and required hemodialysis (HD) for several sessions. The AKI resolved within 2 weeks and further HD was not required. Mental status improved in few days. Follow-up urinalyses showed resolution of microscopic hematuria and crystalluria. We hypothesized that the generic PEG 3350 most likely was contaminated with EG leading to the presentation. A high index of suspicion of contamination of PEG 3350 with EG is required in patients presenting with unexplained high anion gap metabolic acidosis, elevated osmolar gap, lactic acidosis, AKI, calcium oxalate crystalluria, and oxalate crystals on renal biopsy. Further studies are needed to determine whether there is an association between transient glomerular mesangial IgA deposition and crystal nephropathy.

Collapsing Focal Segmental Glomerulosclerosis and Acute Kidney Injury Associated With Chimeric Antigen Receptor T-Cell (CAR-T) Therapy: A Case Report.

Chimeric antigen receptor T (CAR-T) cell treatment is a rapidly emerging therapy for relapsed/refractory hematologic malignancies. Although cytokine release syndrome is a common complication, a concomitant development of biopsy-proven collapsing glomerulopathy and acute kidney injury (AKI) has not been described with CAR-T cell therapy. We report a man in his early 20s with relapsed/refractory pre-B-cell acute lymphoblastic leukemia and compensated liver cirrhosis who received 3 courses of CD19-directed CAR-T cells. After the third CAR-T cell therapy, he developed severe cytokine release syndrome accompanied by new onset of nephrotic syndrome and AKI. Cytokine release syndrome was treated with tocilizumab. His kidney biopsy showed collapsing glomerulopathy, glomerulitis, and interstitial nephritis along with complete podocyte foot-process effacement. Due to disease progression, he was subsequently treated with bispecific CD19-directed CD3 T-cell engager antibody, blinatumomab, during which he developed another episode of cytokine release syndrome with exacerbation of nephrotic-range proteinuria and his AKI progressed to stage 3 chronic kidney disease. Excess cytokine-induced podocyte and renal tubulointerstitial injury and/or "on-target off-tumor" direct renal cell toxicity are the probable mechanisms of kidney injury. Further such reports will increase our understanding of the pathophysiologic basis of kidney injury with CAR-T treatment.

Unmasking of Gitelman Syndrome during Pregnancy in an Adolescent with Thyrotoxic Crisis.

BACKGROUND: Gitelman syndrome (GS) is an inherited salt-losing renal tubulopathy characterized by hypokalemic metabolic alkalosis with hypomagnesemia and hypocalciuria. Patients can be asymptomatic until late adolescence or adulthood, and hence may be discovered incidentally during presentation with other illnesses. GS has been described in association with thyroid disorders and should be considered in patients with hyperthyroidism and persistent hypokalemia, especially in those with associated hypomagnesemia and hypocalciuria. CASE SUMMARY: In this report, we describe an 18-year-old female who presented with hyperemesis gravidarum and thyrotoxicosis, and was incidentally found to have GS, confirmed by the sequence analysis of SLC12A3. Conclusions. Thyroid dysfunctions, such as hypothyroidism, thyrotoxicosis, and thyroid nodules, may develop during pregnancy. A structural homology between the beta-human chorionic gonadotropin and thyroid stimulating hormone molecules, as well as their receptors is probably the basis for the transient thyrotoxicosis crisis during pregnancy. Since hyperemesis in pregnancy can also lead to hypokalemia and alkalosis, a high index of suspicion for GS during pregnancy is required for timely diagnosis and management.

End-stage renal disease in a child with focal segmental glomerulosclerosis associated with a homozygous NUP93 variant.

This report highlights that the genetic causes of FSGS, including NUP93 gene variant, such as the one described in this report, progress to end-stage renal disease rapidly and that the risk of recurrence post-renal transplantation is less likely.

Disparities in Pediatric Patient Portal Activation and Feature Use.

OBJECTIVE: Disparities in adult patient portal adoption are well-documented; however, less is known about disparities in portal adoption in pediatrics. This study examines the prevalence and factors associated with patient portal activation and the use of specific portal features in general pediatrics. MATERIALS AND METHODS: We analyzed electronic health record data from 2012 to 2020 in a large academic medical center that offers both parent and adolescent portals. We summarized portal activation and use of select portal features (messaging, records access and management, appointment management, visit/admissions summaries, and interactive feature use). We used logistic regression to model factors associated with patient portal activation among all patients along with feature use and frequent feature use among ever users (ie, ≥1 portal use). RESULTS: Among 52 713 unique patients, 39% had activated the patient portal, including 36% of patients aged 0-11, 41% of patients aged 12-17, and 62% of patients aged 18-21 years. Among activated accounts, ever use of specific features ranged from 28% for visit/admission summaries to 92% for records access and management. Adjusted analyses showed patients with activated accounts were more likely to be adolescents or young adults, white, female, privately insured, and less socioeconomically vulnerable. Individual feature use among ever users generally followed the same pattern. CONCLUSIONS: Our findings demonstrate that important disparities persist in portal adoption in pediatric populations, highlighting the need for strategies to promote equitable access to patient portals.

Delayed Onset Minimal Change Disease as a Manifestation of Lupus Podocytopathy.

Lupus podocytopathy (LP) is an uncommon manifestation of systemic lupus erythematosus (SLE) and is not included in the classification of lupus nephritis. The diagnosis of LP is confirmed by the presence of diffuse foot process effacement in the absence of capillary wall deposits with or without mesangial immune deposits in a patient with SLE. Here we describe a 13-year-old female who presented with nephrotic syndrome (NS) seven years after the diagnosis of SLE. The renal function had been stable for seven years since the SLE diagnosis, as manifested by the normal serum creatinine, serum albumin and absence of proteinuria. Renal biopsy showed evidence of minimal change disease without immune complex deposits or features of membranous nephropathy. Renal function was normal. The patient had an excellent response to steroid therapy with remission within two weeks. The patient remained in remission five months later during the most recent follow-up. This report highlights the importance of renal histology to determine the accurate etiology of NS in patients with SLE. Circulating factors, including cytokines such as interleukin 13, may play a role in the pathophysiology of LP and needs to be studied further in future larger studies.

An Unusual Occurrence of Erythrocytosis in a Child with Nephrotic Syndrome and Advanced Chronic Kidney Disease.

Background: Anemia is common in patients with nephrotic syndrome (NS) for various reasons. Furthermore, anemia can occur in patients with chronic kidney disease (CKD) predominantly owing to inappropriately low erythropoietin (EPO) production relative to the degree of anemia. However, erythrocytosis is uncommon in patients with NS and advanced CKD who are not treated with exogenous erythropoietin stimulating agents, and when present, will necessitate exploration of the other etiologies. Case summary: Here, we describe an 8-year-old girl with erythrocytosis in association with NS and advanced CKD. The patient was found to have erythrocytosis during the evaluation for hypertensive urgency. She also had nephrotic range proteinuria without edema. Serum hemoglobin and hematocrit were 17 gm/dL and 51%, respectively, despite hydration. Renal function test showed an estimated glomerular filtration rate of 30 mL/min/1.73 m2. There was mild iron deficiency anemia with serum iron saturation of 18%. Serum EPO level was normal. Urine EPO was not measured. Renal biopsy showed evidence of focal segmental glomerulosclerosis. Genetic testing for NS showed mutations in podocyte genes: NUP93, INF2, KANK1, and ACTN4. Gene sequence analysis of genes associated with erythrocytosis showed no variants in any of these genes. She required chronic dialysis ten months later and, subsequently, a renal transplantation 14 months after the initial presentation. Conclusion: Since the serum EPO level was normal, an increased sensitivity to EPO is the most probable mechanism of erythrocytosis. The unusual association of erythrocytosis in patients with NS and advanced CKD needs to be studied further in larger studies.

Renal Transplant Hydroureteronephrosis as a Manifestation of Rejection: An Under-Recognized Entity?

Hydroureteronephrosis (HUN) of the renal transplant (RT) can be obstructive or non-obstructive, refluxing or non-refluxing, and can cause allograft dysfunction. HUN of the RT as a manifestation of rejection is uncommon and has not been described in children. We describe two pediatric RT recipients who presented with late-onset HUN, 5 and 10 years after transplantation. Both had new-onset HUN which occurred at the time of rejection; HUN resolved in both patients after treatment of rejection. Renal function stabilized in both patients without the need for stent or nephrostomy tube placement. There was no obstruction or vesicoureteral reflux (VUR). Edema of the uroepithelial cells leading to transient obstruction causing HUN is a most likely explanation. We conclude that treatment of rejection in patients without obstruction or VUR may lead to resolution of HUN without the need for urological interventions.

Concomitant nephrotic syndrome and tubulointerstitial nephritis in a child with Epstein-Barr virus mononucleosis.

Acute kidney injury (AKI) and nephrotic syndrome (NS) are uncommon manifestations of Epstein-Barr virus (EBV) mononucleosis. We report a 4-year-old boy with Infectious mononucleosis (IM) who presented with dialysis-requiring AKI and NS. Renal biopsy showed severe acute tubular necrosis, mild chronic interstitial nephritis and focal podocyte foot processes effacement. EBV early RNA was not detected in the renal tissue. However, immunophenotyping of peripheral lymphocytes showed increased cytotoxic T cell activity and increased memory B cells. Treatment with steroid led to rapid resolution of NS within 3 weeks. Renal function stabilised. EBV viral capsid antigen (VCA) IgM remained elevated until 4 months before starting to decline when VCA IgG and nuclear antigen started appearing. B lymphocytes are the predominant target cells in EBV infection and additionally may also act as antigen presenting cells to T lymphocytes, thereby eliciting the strong immune response and leading to podocyte and tubulointerstitial injury.