Late diagnosis of Lesch-Nyhan disease complicated with end-stage renal disease and tophi burst: a case report

An insight into Indonesia's progress for newborn screening program: What is currently going on

Objectives

In this literature review, we describe the progress of Indonesia's NBS program (which is heavily centered on CH screening), its current pilot projects, and what lies ahead for this program.

Setting

Since its conception began with congenital hypothyroidism (CH) screening, Indonesia has experienced plodding progress in NBS. There is a shortage of literature discussing the history, or the lack of, and journey of NBS in Indonesia.

Methods

We searched for literature in Pubmed and Google Scholar with keywords such as "Newborn Screening, "Neonatal Screening," "Indonesia," "Asia Pacific," "Congenital Hypothyroidism," "Congenital Adrenal Hyperplasia,""Critical Congenital Heart Disease," "Hearing Loss," and "Inborn Error of Metabolism."

Results

The only mandatory and regulated NBS program in Indonesia is congenital hypothyroid (CH) screening, with some pilot projects being conducted on screening for congenital adrenal hyperplasia (CAH), critical congenital heart disease (CCHD), hearing loss, and to a lesser extent, inborn error of metabolisms (IEMs).

Conclusion

Despite the evidence and benefits, the government does not mandate or regulate newborn diseases such as CHD, CAH, hearing loss, and IEMs. The lack of regulation exists despite multiple pilot projects and studies showing a benefit in at least trying to screen newborns for those conditions.

Clinical Characteristics Suggestive of a Genetic Cause in Cerebral Palsy: A Systematic Review

BACKGROUND

Cerebral palsy (CP) is a clinical diagnosis and was long categorized as an acquired disorder, but more and more genetic etiologies are being identified. This review aims to identify the clinical characteristics that are associated with genetic CP to aid clinicians in selecting candidates for genetic testing.

METHODS

The PubMed database was systematically searched to identify genes associated with CP. The clinical characteristics accompanying these genetic forms of CP were compared with published data of large CP populations resulting in the identification of potential indicators of genetic CP.

RESULLTS

Of 1930 articles retrieved, 134 were included. In these, 55 CP genes (described in two or more cases, n = 272) and 79 candidate genes (described in only one case) were reported. The most frequently CP-associated genes were PLP1 (21 cases), ARG1 (17 cases), and CTNNB1 (13 cases). Dyskinesia and the absence of spasticity were identified as strong potential indicators of genetic CP. Presence of intellectual disability, no preterm birth, and no unilateral distribution of symptoms were classified as moderate genetic indicators.

CONCLUSIONS

Genetic causes of CP are increasingly identified. The clinical characteristics associated with genetic CP can aid clinicians regarding to which individual with CP to offer genetic testing. The identified potential genetic indicators need to be validated in large CP cohorts but can provide the first step toward a diagnostic algorithm for genetic CP.

Renal function, sex and age influence purines and pyrimidines in urine and could lead to diagnostic misinterpretation

Glomerular filtration rate (GFR) is commonly used in clinical practice for the diagnosis and follow-up of chronic kidney disease. Screening for inborn errors of metabolism (IEM) is based on analysis of biomarkers in urine, reported by their ratio to urinary creatinine (crn). Impaired renal function may complicate the interpretation of several biomarkers used for screening of IEM. Our goal was to investigate the influence of kidney function, in terms of measured GFR (mGFR) on purines and pyrimidines in urine, in addition to the relationship to sex, age, pH and ketosis. Children (n = 96) with chronic kidney disease (CKD), in different CKD stages, were included. Urine samples were obtained prior to the injection of iohexol. Serum samples at 7 time-points were used to calculate mGFR based on iohexol plasma clearance. The association with sex, age, ketosis and pH was examined in samples of the laboratory production from 2015 to 2021 (n = 8192). Age was a highly significant covariate for all markers. GFR correlated positively to several purines and pyrimidines; the ratios hypoxanthine/crn, xanthine/crn and urate/crn (p = 2.0 × 10-14, < 3 × 10-15 and 7.2 × 10-4, respectively), and the ratios orotic acid/crn, uracil/crn, and carbamyl-β-alanine/crn (p = 0.03, 1.4 × 10-6 and 0.003, respectively). The values of urate/crn, xanthine/crn, uracil/crn, and carbamyl-β-alanine/crn were higher in females above 16 years of age. Ketosis and pH influenced some markers. In conclusion, decreased renal function interferes with the excretion of urinary purines and pyrimidines, and this could change decision limits substantially, e.g. result in false negative results in Lesch-Nyhan syndrome. SYNOPSIS: GFR influences purines and pyrimidines in urine. Clinical Trial Registration: ClinicalTrials.gov, Identifier NCT01092260, https://clinicaltrials.gov/ct2/show/NCT01092260?term=tondel&rank=2.

Epidemiology and Outcomes of Children with Kidney Failure Receiving Kidney Replacement Therapy in Australia and New Zealand

Introduction

The incidence and outcomes of kidney replacement therapy (KRT) have been well-studied in adults, but much less so in children. This study aimed to investigate the epidemiology and outcomes of KRT in children in Australia and New Zealand from 2000 to 2020.

Methods

Children aged <18 years initiating KRT in Australia and New Zealand between January 1, 2000 and December 31, 2020 and reported to the Australia and New Zealand Dialysis and Transplant Registry were included. Patient survival, technique-survival, and graft survival were analyzed by Cox regression analyses.

Results

Overall, 1058 children (median [interquartile range (IQR)] age 11 [5-15] years, 41% female, 66% White) were followed-up with for a median period of 12.3 years. First KRT modalities were peritoneal dialysis (PD; 48%), hemodialysis (HD; 34%), and kidney transplantation (KT; 18%). Pre-emptive KT incidence was highest in Caucasian children (80.4%) and lowest in the Indigenous population (3.2%). There was no difference in 5-year patient survival rates between 2011 and 2020 (96.9%, 95% confidence interval [CI] 93.8-98.4) and the preceding decade, 2000-2010 (94.5%, 95% CI 90.4-96.8) (P = 0.79). There was no difference in 5-year death-censored technique survival between 2011 and 2020 (51.2%, 95% CI 39.1-62) and 2000-2010 (48.8%, 95% CI 40.5-56.6) (P = 0.27). However, 5-year derath-censored graft survival was significantly higher in 2011-2020 (88.4%, 95% CI 84.6-91.4) than in 2000-2010 (84.3%, 95% CI 80.4-87.5) (P < 0.001).

Conclusions

PD is the most commonly prescribed KRT modality for children in Australia and New Zealand. Patient-survival, technique-survival, and graft survival rates are excellent and graft survival has improved over the last 2 decades.

Nephropathy in a Child with Severe Recessive Dystrophic Epidermolysis Bullosa Treated with Cyclophosphamide: A Case Report

Long-term inflammation and recurrent skin infection in recessive dystrophic epidermolysis bullosa (RDEB) are associated with the presence of immunoglobulin A (IgA)-containing immune complexes in the glomerulus. Only eight pediatric RDEB cases with IgA nephropathy (IgAN) have been documented in English-language literature. Most RDEB patients with IgAN progress to kidney failure within 5 years of diagnosis, indicating that these patients may require more intensive early treatment compared to those with primary IgAN. However, diagnosing IgAN in RDEB cases with severe cutaneous manifestations can be challenging. Herein, we report a rare case of nephropathy in an 11-year-old boy with severe RDEB and a frameshift mutation on the COL7A1 gene, which may manifest as kidney disorders. He presented with persistent hematuria and progressing proteinuria. A presumptive IgAN diagnosis was based on clinical features and increased IgA serum levels, as kidney biopsy was refused by his parents. Nephrotic-range proteinuria persisted despite initial steroid and lisinopril treatment. Monthly intravenous cyclophosphamide (IV CPA; 500 mg/m2) led to proteinuria remission and preservation of kidney function for 2 years posttreatment. We conclude that COL7A1 mutations may result in extracutaneous manifestations, including kidney disorders. The association between IgA-containing immune complex deposits in the glomerulus and recurrent skin infection in RDEB may indicate IgAN, particularly when kidney biopsy is infeasible due to severe skin manifestations. In our case, positive results with IV CPA suggest further investigation is needed to explore its potential role in non-rapidly progressing IgAN in children with RDEB.

Rituximab, Mycophenolic Acid, and Calcineurin Inhibitors Achieve Long-Term Remission in Pediatric Focal Segmental Glomerulosclerosis with Steroid-Resistant and Frequently Relapsing Nephrotic Syndrome: A Report of Two Cases

Studies investigating the effect of rituximab in children with nephrotic syndrome (NS) due to focal segmental glomerulosclerosis (FSGS) have reported conflicting results, with some concluding that patients may require additional immunosuppressive therapy to achieve and/or maintain long-term remission. We report successful treatment of pediatric FSGS with rituximab infusions, followed by maintenance immunosuppression with mycophenolic acid (MPA) and a calcineurin inhibitor (CNI) in 1 patient with refractory steroid-resistant NS (SRNS), and one with frequently relapsing NS (FRNS). Case 1 is a patient with refractory SRNS due to FSGS. MPA and tacrolimus induced complete remission within 6 months following rituximab treatment. Remission was maintained for over 2 years, and the patient's kidney function and body height also returned to normal ranges within this time. Case 2 is a patient with FRNS due to FSGS, who was treated with rituximab followed by MPA and cyclosporine, which successfully prevented relapses for 18 months, that is, at the end point of the observation. Our case report demonstrates that rituximab and a combination of CNIs and MPA can be effective in achieving complete remission in pediatric refractory SRNS and sustaining remission in pediatric FSGS with FRNS and SRNS for several years. This treatment regimen has the advantage of eliminating the need for long-term high-dose steroid treatments, allowing 1 patient to achieve normal growth and recover from other adverse steroid effects.

Distal renal tubular acidosis presenting with an acute hypokalemic paralysis in an older child with severe vesicoureteral reflux and syringomyelia: a case report

Background

Distal renal tubular acidosis (dRTA) is the most common type of renal tubular acidosis (RTA) in children. Pediatric dRTA is usually genetic and rarely occurs due to acquired issues such as obstructive uropathies, recurrent urinary tract infections (UTIs), and chronic kidney disease (CKD). Although persistent hypokalemia frequently occurs with dRTA, acute hypokalemic paralysis is not frequently reported, especially in older children.

Case presentation

An eight-year-old girl presented with an acute first episode of paralysis. A physical examination revealed normal vital signs, short stature consistent with her genetic potential, and decreased muscle strength of her upper and lower extremities. Preexisting conditions included stage 4 CKD due to recurrent UTIs, severe vesicoureteral reflux and bilateral hydronephrosis, neurogenic bladder, and multisegment thoracic syringomyelia. Her laboratory work-up revealed hypokalemic, hyperchloremic metabolic acidosis with a normal anion gap. She also had a urine osmolal gap of 1.9 mOsmol/kg with a high urine pH. Intravenous potassium replacement resulted in a complete resolution of her paralysis. She was diagnosed with dRTA and discharged with oral bicarbonate and slow-release potassium supplementation.

Conclusions

This case report highlights the importance of considering dRTA in the differential diagnosis of hypokalemic acute paralysis in children. Additionally, in children with neurogenic lower urinary tract dysfunction and recurrent UTIs, early diagnosis of spinal cord etiology is crucial to treat promptly, slow the progression of CKD, and prevent long-term complications such as RTA.

Description of the Molecular and Phenotypic Spectrum of Lesch-Nyhan Disease in Eight Chinese Patients

Background: Lesch-Nyhan disease (LND) is a rare disorder involving pathogenic variants in the HPRT1 gene encoding the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGPRT) that result in hyperuricemia, intellectual disability, dystonic movement disorder, and compulsive self-mutilation. The purpose of the present study was to characterize the genetic basis of LND and describe its phenotypic heterogeneity by identifying the variation in the HPRT1 gene in a cohort of Chinese LND patients. Results: The median age at diagnosis was 31 mo (interquartile range (IQR): 7-76 mo), and the initial manifestations were mainly head control weakness and motor development delay. The median age of self-mutilation behavior onset was 19 mo (IQR: 17-24 mo), and all patients were required to travel in a wheelchair and fall into the predicament of compulsive self-harm behavior. There were two patients whose blood uric acid levels were normal for their high urinary acid excretion fraction without taking uric acid-lowering drugs. Seven different pathogenic variants of the HPRT1 gene were identified among eight independent pedigrees, including four novel mutations [c.299 (exon 3) T > A; loss (exon: 6) 84 bp; c.277_281delATTGC; c.468_470delGAT]. The pathogenic variant sites were mainly concentrated in exon 3, and truncating mutations (including frameshift mutations and nonsense mutations) were the most common genetic variant types (5/7, 71.4%). Conclusion: The present study described the phenotypic and molecular spectrum of LND in eight Chinese families, including four novel mutations, which expands our understanding of LND.

A novel uric acid biosensor based on regular Prussian blue nanocrystal/ upright graphene oxide array nanocomposites

Objective:

Regular Prussian blue nanocrystals (RPB) were grown upright on graphene oxide flakes (GO), which were on the surface of a custom screen-printed carbon electrode (SPCE), using a spray method assisted by a constant magnetic field (CMF).

Method:

After immobilizing uricase, the uric acid biosensor Uricase/RPB/CMF-GO/SPCE was obtained. The detection range of the sensor response to UA was 0.005~2.525 mM, and the detection limit was as low as 3.6 μM. The cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results showed that compared to amorphous electrodeposited Prussian blue (EDPB), RPB more favorably accelerated electron transport.

Result:

This novel uric acid biosensor exhibits high sensitivity over, a wide concentration range, strong anti- interference ability, and good stability and reproducibility.

Conclusion:

Thus, it has good application prospects for determining uric acid in physiological samples

Silent Hypertensive Crisis in an Adolescent: First Case Report of Pediatric Pheochromocytoma from Indonesia

Secondary hypertension in children, to the rare extent, can be caused by endocrine factors such as pheochromocytoma, an adrenal tumor that secretes catecholamine. Only a few cases have been reported in the past 3 decades. To the best of our knowledge, this is the first case report of pediatric pheochromocytoma from Indonesia. We reviewed a case of a 16-year-old Indonesian boy with history of silent hypertensive crisis who was referred from a remote area in an island to the pediatric nephrology clinic at Cipto Mangunkusumo Hospital, Jakarta, Indonesia. Despite medications, his symptoms persisted for 14 months. At the pediatric nephrology clinic, pheochromocytoma was suspected due to symptoms of catecholamine secretion presented, which was palpitation, diaphoresis, and weight loss. However, as the urine catecholamine test was unavailable in Indonesia, the urine sample was sent to a laboratory outside the country. The elevated level of urine metanephrine, focal pathological uptake in the right adrenal mass seen on ¹³¹I-MIBG, and histopathology examination confirmed the suspicion of pheochromocytoma. Following the tumor resection, he has been living with normal blood pressure without antihypertensive medications. This case highlights that pheochromocytoma should always be included in the differential diagnoses of any atypical presentation of hypertension. In limited resources setting, high clinical awareness of pheochromocytoma is required to facilitate prompt referral. Suspicion of pheochromocytoma should be followed by measurement of urine metanephrine levels. Early diagnosis of pheochromocytoma would fasten the optimal cure, alleviate the symptoms of catecholamine release, and reverse hypertension.

Experience of the first 6 years of pediatric kidney transplantation in Indonesia: A multicenter retrospective study

BACKGROUND

Pediatric kidney transplantation was only introduced in Indonesia in 2013. We therefore aimed to assess the characteristics and outcomes of transplants performed from its inception to January 2019.

METHOD

The study had a dual-center retrospective design. We examined the records of kidney transplant recipients and then calculated patient and graft survival rates by Kaplan-Meier survival analysis with 95% confidence intervals (95% CI).

RESULTS

In total, 12 kidney transplantations were performed in eleven children during the study period; among these, ten were boys, and nine had renal failure caused by congenital anomaly of the kidney or urinary tract. All donors were living, and all recipients were on dialysis at the time of transplantation, when their median age was 14.5 years (range, 8-19 years). Three patients died of infection in the first year of follow-up and two lost their allograft by the time of their last follow-up (median, 13 months; range, 4-69 months). The 1-year patient survival rate was therefore 68.18% (95% CI, 29.72%-88.61%), which remained unchanged at 3 and 5 years. However, the non-death-censored graft survival rates at 1, 3, and 5 years were 68.18% (95% CI, 29.72%-88.61%), 51.14% (95% CI, 14.5%-79.46%), and 25.57% (95% CI, 1.38%-64.78%), respectively.

CONCLUSION

Patient and graft survival rates after pediatric kidney transplantation in Indonesia are lower than those reported in other countries. Closer patient follow-up and stricter adherence to guidelines could improve transplant outcomes, but we must seek to improve the balance between infection and rejection.

Dressing <em>versus</em> non-dressing technique for long-term exit-site care in children on continuous ambulatory peritoneal dialysis: a single-center retrospective cohort study

BACKGROUND There is no consensus on the optimal long-term exit-site care strategy in children on long-term peritoneal dialysis (PD) worldwide. Thus, this study aimed to compared the dressing versus non-dressing technique for long-term exit-site care to prevent PD-related infection. METHODS This retrospective cohort study involved patients aged <18 years with end-stage kidney disease who were on continuous ambulatory PD at the Cipto Mangunkusumo Hospital between March 2014 and March 2019. Long-term exit-site care was initiated within 3 months after the insertion of Tenckhoff catheter. The patients and caregivers can choose to either maintain the dressing method or change to the non-dressing method for the subsequent long-term exit-site care. The follow-up was performed until the following 6 months. RESULTS Out of 34 patients, 18 were treated without dressing and 16 with dressing technique. The peritonitis rates were 0.17 and 0.06 episodes per year at risk in the non-dressing and dressing groups; the adjusted incidence rate ratio was 0.4 (95% confidence interval = 0.04–3.25; p = 0.4). Allergic contact dermatitis occurred in 15/18 (83%) patients in the non-dressing group and 11/16 (69%) in the dressing group before long-term exit-site care was applied. Ultimately, no patient in the non-dressing group developed allergic contact dermatitis, whereas 11 (69%) had allergic contact dermatitis in the dressing group at the end of follow-up. CONCLUSIONS Non-dressing technique may increase the risk of peritonitis in children on long-term PD; however, it is beneficial for children vulnerable to allergic contact dermatitis.

Successful Treatment of Hepatitis C Virus Infection Using Direct-Acting Antiviral Agents (DAAs) in Adolescents with Kidney Transplantation: A Case Series

INTRODUCTION

Hepatitis C virus (HCV) infection is common among end-stage renal disease patients undergoing hemodialysis. The standard treatment for HCV infection has been interferon-ribavirin combination prior to renal transplantation. However, compared to direct-acting antiviral agents (DAAs), the risk of graft rejection is higher with interferon therapy. Many recent studies have investigated the efficacy and safety of DAAs for treating HCV infection in kidney disease in adults; however, it has not been established in pediatric patients. To the best of our knowledge, this is the first report describing successful treatment using the DAAs sofosbuvir/daclatasvir in two pediatric kidney transplant recipients who had HCV genotype 1a infection without liver fibrosis.

CASE PRESENTATION

Case 1 describes a 13-year-old Indonesian boy who had undergone hemodialysis since 2014 after being diagnosed with end-stage renal disease (ESRD) secondary to bilateral renal hypoplasia. Later, he had HCV infection and was treated with interferon-based therapy with ribavirin prior to living-related renal transplantation (LRRT). The HCV was undetected and his liver function normalized six months after treatment initiation. However, 10 months after treatment initiation, he had HCV virological breakthrough, leading to cessation of interferon therapy. Plans for LRRT were continued and HCV treatment using DAAs was set up to be given post LRRT. Case 2 describes a 14-year-old Indonesian girl who also had hemodialysis prior to LRRT after she was diagnosed with ESRD secondary to nephrotic syndrome. Later, she had HCV infection and was treated with interferon and ribavirin prior to the live-unrelated renal transplantation. HCV infection did not resolve, in addition, she experienced thrombocytopenia-which is a side effect of interferon-resulting in termination of interferon treatment. Both cases were treated with DAAs one year following renal transplantation after reaching stable graft function, leading to achievement of sustained virological response at 24 weeks.

CONCLUSION

Post-transplantation treatment of chronic HCV is preferred in KTRs. The sofosbuvir/daclatasvir regimen as an interferon-free therapy is a safe, effective option for HCV infection in pediatric KTRs, who can tolerate sofosbuvir/daclatasvir well and respond favorably without significant adverse events.

Low-Dose Maintenance Intravenous Iron Therapy Can Prevent Anemia in Children with End-Stage Renal Disease Undergoing Chronic Hemodialysis

Iron deficiency anemia is common in children with end-stage renal disease (ESRD) on long-term hemodialysis receiving erythropoiesis-stimulating agents. One approach to maintain the iron profile and hemoglobin levels is maintenance therapy with regular low doses of intravenous (IV) iron after initial iron repletion therapy; however, evidence for the benefits of this approach is lacking. This study evaluated the effect of IV iron maintenance therapy on anemia in children on regular hemodialysis. This retrospective cohort study included 41 pediatric ESRD patients with normal hemoglobin and iron status who underwent regular hemodialysis at the Pediatric Dialysis Unit of Cipto Mangunkusumo Hospital, Indonesia, between January 2015 and April 2019. Among these, 21 received IV iron maintenance therapy with two doses of 2 mg/kg of IV iron sucrose every 2 weeks (the treatment group) and 20 did not (the comparison group). Changes in hemoglobin and transferrin saturation were assessed after 6 weeks of observation and compared between the two groups. There was a significant reduction in the mean hemoglobin level compared with the baseline level in the comparison group (21 g/L; 95% CI, 9.3–33 g/L; p=0.001) but not in the treatment group (0.7 g/L; 95% CI, −6.6–8 g/L; p=0.84). The risk of anemia was lower in the treatment group (relative risk = 0.42; 95% CI, 0.22–0.79; p=0.003). Although majority of the patients had high baseline ferritin level, this study indicates that in our setting, ferritin may not be a reliable parameter to review the iron status, as it can be affected by chronic inflammation. Hence, the decision to start IV iron maintenance therapy in patients with hyperferritinemia should consider the patient's clinical condition and morbidity. To conclude, the coadministration of IV iron maintenance therapy is beneficial for maintaining hemoglobin levels and preventing anemia in children with ESRD who are undergoing regular hemodialysis, have achieved the target hemoglobin levels, and have normal iron status.