Poorly differentiated SMARCB1/INI1-negative chordomas.

AIMS: To analyze the clinicopathological characteristics of poorly differentiated chordomas (PDCs) with SMARCB1/INI1 loss in children. MATERIALS: Four cases of PDCs were included in the study. METHODS: Immunohistochemistry was performed with respect to brachyury, Glut-1, keratin 18, keratin 19, INI1, vimentin, S-100, CK, EMA, GFAP, etc. Fluorescence in situ hybridization (FISH) was performed for SMARCB1/INI1 from 3 patients. RESULTS: Histologically, contrary to typical histologic features for conventional chordomas, 4 tumors were composed of ovoid or atypical fusiform cells. Sporadic physaliphorous cells were evident. Tumor cells had large vacuoles in the cytoplasm that were even remarkable on the imprint cytology slide. By immunohistochemistry, each case revealed loss of SMARCB1/INI1 expression and nuclear expression of brachyury. Glut-1, keratin 18, keratin 19, CK, EMA, and vimentin were positive in these PDCs. Except for 1 patient who had not yet completed FISH, the other 3 cases demonstrated the loss of SMARCB1/INI1 gene by fluorescence in situ hybridization. CONCLUSION: Poorly differentiated SMARCB1/INI1-negative chordoma is a unique subset of chordoma representing a clinically, histopathologically, and molecularly distinct entity with rapid progression and poor prognosis which should not be confused with conventional chordomas. Sporadic physaliphorous cells (tumor cells with large vacuoles in the cytoplasm) provided important diagnostic clues of PDCs. Combination use of characteristic markers of notochord cells (brachyury, Glut-1, keratin 18, and keratin 19) along with INI1 were effective diagnostic tools.

TJP2 hepatobiliary disorders: Novel variants and clinical diversity.

To assess the spectrum of pediatric clinical phenotypes in TJP2 disease, we reviewed records of our seven patients in whom intrahepatic cholestasis was associated with biallelic TJP2 variants (13; 12 novel) and correlated clinical manifestations with mutation type. The effect of a splicing variant was analyzed with a minigene assay. The effects of three missense variants were analyzed with protein expression in vitro. Our patients had both remitting and persistent cholestasis. Three exhibited growth retardation. Six responded to treatment with cholestyramine, ursodeoxycholic acid, or both. Two had cholecystolithiasis. None required liver transplantation or developed hepatocellular or cholangiocellular malignancy. None manifested extrahepatic disease not attributable to effects of cholestasis. The variant c.2180-5T>G resulted in exon 15 skipping with in-frame deletion of 32 amino acid residues in TJP2. The three missense variants decreased but did not abolish TJP2 expression. Patients with truncating or canonical splice-site variants had clinically more severe disease. TJP2 disease in children includes a full clinical spectrum of severity, with mild or intermittent forms as well as the severe and minimal forms hitherto described. Biallelic TJP2 variants must be considered in children with clinically intermittent or resolved intrahepatic cholestasis.

ABCB11 deficiency presenting as transient neonatal cholestasis: Correlation with genotypes and BSEP expression.

BACKGROUND & AIMS: ABCB11 deficiency presenting in infancy is believed generally to manifest as persistent/progressive cholestasis. We describe a group of patients with biallelic ABCB11 variants whose disorder manifested as transient neonatal cholestasis (TNC). METHODS: Neonatal intrahepatic cholestasis in 68 children (31 males) with biallelic predictedly pathogenic variants (PPV) in ABCB11 was classified as transient (TNC group, n = 23, 11 males), intermittent (benign recurrent intrahepatic cholestasis [BRIC] group, n = 3, 1 male) or persistent/ progressive (progressive familial intrahepatic cholestasis [PFIC] group, n = 42, 19 males). Clinical, genetic and bile salt export pump (BSEP) expression information was correlated with outcomes. RESULTS: The median onset age of jaundice was 3 days (birth to 2 months) for the TNC group and 10.5 days (birth to 3 months) for the PFIC group (P = .034). The median length of follow-up of TNC patients was 44 months (12 months-168 months). At presentation, hepatobiliary-injury biomarker values were similar between the groups (P > .05). TNC patients (17/23) more often than PFIC patients (20/42, P = .041) harboured biallelic non-null variants (predicted not to terminate translation prematurely). TNC patient livers (7/7) more often than PFIC patient livers (5/16, P = .005) expressed immunohistochemically detectable BSEP. Kaplan-Meier analysis showed better prognosis for patients with BSEP expression (P = .009). Too few BRIC patients were available for statistical study. CONCLUSIONS: Neonatal cholestasis associated with biallelic PPV in ABCB11 can resolve temporarily or persistently in one third of cases. Resolution is more likely in patients with biallelic non-null PPV or with liver BSEP expression.

Defects in myosin VB are associated with a spectrum of previously undiagnosed low γ-glutamyltransferase cholestasis.

Hereditary cholestasis in childhood and infancy with normal serum gamma-glutamyltransferase (GGT) activity is linked to several genes. Many patients, however, remain genetically undiagnosed. Defects in myosin VB (MYO5B; encoded by MYO5B) cause microvillus inclusion disease (MVID; MIM251850) with recurrent watery diarrhea. Cholestasis, reported as an atypical presentation in MVID, has been considered a side effect of parenteral alimentation. Here, however, we report on 10 patients who experienced cholestasis associated with biallelic, or suspected biallelic, mutations in MYO5B and who had neither recurrent diarrhea nor received parenteral alimentation. Seven of them are from two study cohorts, together comprising 31 undiagnosed low-GGT cholestasis patients; 3 are sporadic. Cholestasis in 2 patients was progressive, in 3 recurrent, in 2 transient, and in 3 uncategorized because of insufficient follow-up. Liver biopsy specimens revealed giant-cell change of hepatocytes and intralobular cholestasis with abnormal distribution of bile salt export pump (BSEP) at canaliculi, as well as coarse granular dislocation of MYO5B. Mass spectrometry of plasma demonstrated increased total bile acids, primary bile acids, and conjugated bile acids, with decreased free bile acids, similar to changes in BSEP-deficient patients. Literature review revealed that patients with biallelic mutations predicted to eliminate MYO5B expression were more frequent in typical MVID than in isolated-cholestasis patients (11 of 38 vs. 0 of 13). CONCLUSION: MYO5B deficiency may underlie 20% of previously undiagnosed low-GGT cholestasis. MYO5B deficiency appears to impair targeting of BSEP to the canalicular membrane with hampered bile acid excretion, resulting in a spectrum of cholestasis without diarrhea. (Hepatology 2017;65:1655-1669).

Ectopic nephrogenic rests in children: A series of 13 cases in a single institution.

PURPOSE: Ectopic nephrogenic rests (ENR) are extremely rare, and their diagnosis and treatment have not yet been standardized. Our study aimed to analyze the clinical and pathological features of ENR in children and explore the optimal methods for diagnosis and treatment. METHODS: A retrospective, single-center, case series study of 13 children with ENR was performed. Clinical manifestations, work-up, pathological features, and treatment methods were analyzed, and the postoperative status was evaluated at follow-up. RESULTS: The study cohort included seven males and six females aged 1/4-19 months, who were divided into two subgroups: group 1 (pure ENR, cases 1-3) and group 2 (ENR associated with teratoma, cases 4-13). The patients commonly presented with a painless mass or an incidental finding in surgery. The ENR were detected in the lumbosacral and sacrococcygeal region (five cases), retroperitoneal area (five cases), testis (one case), gubernaculum testis (one case), and stomach (one case). Radiological findings showed a mixed-density mass or a mixed-signal-intensity lesion in group 2. All the patients underwent surgical resection, and all except two were event-free in a follow-up period of 2-154 months. Case 8 showed recurrence, and extended surgery was performed. Case 7 developed metastases and received chemotherapy. CONCLUSIONS: ENR are rare among children and have no specific clinical manifestations, lab tests, and radiological features. Different treatment strategies may be adopted based on the diagnosis. Complete resection can generally be achieved, and the prognosis is excellent in most cases. However, relapse or metastasis may occur in a small subset of patients. Close follow-up is mandatory to detect recurrence and metastasis early.

A novel homozygous mutation in the glycerol-3-phosphate dehydrogenase 1 gene in a Chinese patient with transient infantile hypertriglyceridemia: a case report.

BACKGROUND: Transient infantile hypertriglyceridemia (HTGTI) is an autosomal recessive disorder caused by mutations in the glycerol-3-phosphate dehydrogenase 1 (GPD1) gene. CASE PRESENTATION: We report a case of HTGTI in a Chinese female infant. She presented with hepatomegaly, hypertriglyceridemia, moderately elevated transaminases, and hepatic steatosis at 3.5 months of age. A novel mutation c.523C>T, p. (Q175*) was identified in GPD1. The patient was a homozygote and her parents were heterozygous for the mutation. Ultrastructural study showed intrahepatocytic lipid droplets. CONCLUSIONS: This is the first reported case of HTGTI in Chinese, expanding the worldwide distribution of HTGTI and the mutation spectrum of GPD1.

Clinicopathological Features of Pediatric Insulinoma: A Single-Centre Study.

Aims/Background: Insulinoma is an extremely rare condition in pediatric patients. This study aims to examine the pathological and clinical characteristics of pediatric insulinoma. Methods: A retrospective, single-center study was conducted involving five pediatric patients diagnosed with insulinoma. The study involved evaluating the postoperative status of the patients during follow-up and analyzing their clinical manifestations, diagnostic work-up, pathological findings, and therapeutic approaches. Results: The study cohort comprised four males and one female, aged between 4 and 9 years. Common symptoms included dizziness and fatigue. The insulinomas were located in various parts of the pancreas: two in the head, one in the neck, one in the body, and one in the tail. After undergoing subtotal pancreatectomy, four patients experienced no side effects during a follow-up period of 41 to 153 months. One patient, who underwent an incomplete pancreatic resection, required ongoing postoperative treatment with 150 mg Creon due to pancreatic enzyme deficiency. Postoperative pathological results indicated that all cases were low-grade neuroendocrine tumours, classified as grade 1 (G1) or grade 2 (G2). Two cases exhibited capsule invasion, and one case showed microvascular invasion. Despite these invasions, no recurrences or metastases have been observed to date. Conclusion: Surgical resection is a viable treatment option for pediatric insulinoma, yielding a favorable prognosis. The presence of capsular and microvascular invasions does not seem to affect the overall prognosis in these cases.

Early onset and liver failure indicating poor prognosis of infant liver failure syndrome type 1.

BACKGROUND: Infantile liver failure syndrome type 1 (ILFS1, OMIM #615,438), caused by leucyl-tRNA synthase 1 (LARS1, OMIM *151,350) deficiency, is a rare autosomal-recessive disorder. The clinical manifestations, molecular-genetic features, and prognosis of LARS1 disease remain largely elusive. METHODS: Three new instances of ILFS1 with confirmed variants in LARS1, encoding LARS1, were identified. Disease characteristics were summarized together with those of 33 reported cases. Kaplan-Meier analysis was performed to assess prognostic factors in ILFS1 patients. RESULTS: The 3 new ILFS1 patients harbored 6 novel variants in LARS1. Among the 36 known patients, 12 died or underwent liver transplantation. The main clinical features of ILFS1 were intrauterine growth restriction (31/32 patients in whom this finding was specifically described), failure to thrive (30/31), hypoalbuminemia (32/32), microcytic anemia (32/33), acute liver failure (24/34), neurodevelopmental delay (25/30), seizures (22/29), and muscular hypotonia (13/27). No significant correlations were observed between genotype and either presence of liver failure or clinical severity of disease. Kaplan-Meier analysis indicated that age of onset < 3mo (p = 0.0015, hazard ratio = 12.29, 95% confidence interval [CI] = 3.74-40.3), like liver failure (p = 0.0343, hazard ratio = 6.57, 95% CI = 1.96-22.0), conferred poor prognosis. CONCLUSIONS: Early age of presentation, like liver failure, confers poor prognosis in ILFS1. Genotype-phenotype correlations remain to be established.

Efficacy of rituximab-containing regimens used as first-line and rescue therapy for giant cell hepatitis with autoimmune hemolytic anemia a retrospective study.

OBJECTIVE: To evaluate the efficacy of rituximab (RTX)-containing therapy as first-line as well as rescue treatment for giant cell hepatitis with autoimmune hemolytic anemia (GCH-AHA). METHODS: This retrospective study recruited patients diagnosed with GCH-AHA and treated with conventional immunosuppressor regimens consisting of prednisone or RTX-containing regimes consisting of RTX and prednisone, with or without another immunosuppressor. The primary outcomes were the complete remission (CR) rate and time-period required for CR. The secondary outcomes included relapses and adverse events. RESULTS: Twenty patients (8 females and 12 males; age range 1-26 months), 15 receiving conventional regimens and 5 receiving RTX-containing regimens, were included. The CR rates were 73.3 % (11/15) and 100 % (5/5) in the conventional and RTX-containing groups, respectively. The time-period required for CR was significantly shorter in the RTX-containing group than in the conventional group (6 (3-8) versus 14 (5-25) months, P = 0.015). Relapses occurred in 30.8 % (4/13) of patients in the conventional group; all achieved CR after adding RTX. Relapses occurred in 40.0 % (2/5) of patients in the RTX-containing group; both achieved CR after adding intravenous immune globulins or tacrolimus. Transient low immunoglobulin and infections were recorded in both groups. Treatment withdrawal was achieved in 73.3 % (11/15) and 60.0 % (3/5) of patients receiving conventional and RTX-containing regimens after 36 (2-101) and 22 (4-41) months, respectively. Two patients in conventional group died of disease progression and infection. CONCLUSIONS: RTX-containing first-line therapy achieves CR of GCH-AHA more quickly than the conventional therapy. RTX is efficacious when added to rescue therapy.

Case report: Novel DGUOK variants associated with idiopathic non-cirrhotic portal hypertension in a Han Chinese child.

DGUOK deficiency has primarily been associated with lethal hepatic failure with or without hypotonia, nystagmus, and psychomotor retardation, features typical of mitochondrial disease. A study in 3 Turkish children identified homozygosity for a variant in DGUOK as associated with idiopathic non-cirrhotic portal hypertension (INCPH). However, no further instances of INCPH associated with DGUOK variants have been reported. We here describe a fourth patient with DGUOK variants and childhood-onset INCPH, a 12-year-old Han Chinese boy, reporting clinical manifestations, histopathologic findings, and results of genetic studies. The child presented with hepatosplenomegaly; portal hypertension and hypersplenism were found. Vascular changes with hepatic fibrosis (Scheuer score 3) were observed on liver biopsy. Whole-exome sequencing and family analyses revealed compound heterozygosity for the DGUOK (NM_080916.3) variants c.778_781dup, (p.Thr261Serfs*28) and c.831_832del, (p.*278Thrfs*9) in the proband. These observations support ascription of instances of INCPH in children to variation in DGUOK.

Neonatal Dubin-Johnson Syndrome and its Differentiation from Biliary Atresia.

Background and Aims: The aim was to determine if liver biochemistry indices can be used as biomarkers to help differentiate patients with neonatal Dubin-Johnson syndrome (nDJS) from those with biliary atresia (BA). Methods: Patients with genetically-confirmed nDJS or cholangiographically confirmed BA were retrospectively enrolled and randomly assigned to discovery or verification cohorts. Their liver chemistries, measured during the neonatal period, were compared. Predictive values were calculated by receiver operating characteristic curve analysis. Results: A cohort of 53 nDJS patients was recruited, of whom 13 presented with acholic stools, and 14 underwent diagnostic cholangiography or needle liver biopsy to differentiate from BA. Thirty-five patients in the cohort, with complete biochemical information measured during the neonatal period, were compared with 133 infants with cholangiographically confirmed BA. Total and direct bilirubin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bile acids, alkaline phosphatase, and gamma-glutamyl transferase were significantly lower in nDJS than in BA. In the discovery cohort, the areas under the curve for ALT and AST were 0.908 and 0.943, respectively. In the validation cohort, 13/15 patients in the nDJS group were classified as nDJS, and 10/53 in the BA control group were positive (p<0.00001) with an ALT biomarker cutoff value of 75 IU/L. Thirteen of 15 patients were classified as nDJS and none were classified positive in the BA group (13/15 vs. 0/53, p<0.00001) with an AST cutoff of 87 IU/L. Conclusions: Having assembled and investigated the largest cohort of nDJS patients reported to date, we found that nDJS patients could be distinguished from BA patients using the serum AST level as a biomarker. The finding may be clinically useful to spare cholestatic nDJS patients unnecessary invasive procedures.

N 6-Methyladenosine Methylomic Landscape of Ureteral Deficiency in Reflux Uropathy and Obstructive Uropathy.

Background: Congenital anomalies of the kidneys and urinary tracts (CAKUT) represent the most prevalent cause for renal failure in children. The RNA epigenetic modification N 6-methyladenosine (m6A) methylation modulates gene expression and function post-transcriptionally, which has recently been revealed to be critical in organ development. However, it is uncertain whether m6A methylation plays a role in the pathogenesis of CAKUT. Thus, we aimed to explore the pattern of m6A methylation in CAKUT. Methods: Using m6A-mRNA epitranscriptomic microarray, we investigated the m6A methylomic landscape in the ureter tissue of children with obstructive megaureter (M group) and primary vesicoureteral reflux (V group). Results: A total of 228 mRNAs engaged in multiple function-relevant signaling pathways were substantially differential methylated between the "V" and "M" groups. Additionally, 215 RNA-binding proteins that recognize differentially methylated regions were predicted based on public databases. The M group showed significantly higher mRNA levels of m6A readers/writers (YTHDF1, YTHDF2, YTHDC1, YTHDC2 and WTAP) and significantly lower mRNA levels of m6A eraser (FTO) according to real-time PCR. To further investigate the differentially methylated genes, m6A methylome and transcriptome data were integrated to identified 298 hypermethylated mRNAs with differential expressions (265 upregulation and 33 downregulation) and 489 hypomethylated mRNAs with differential expressions (431 upregulation and 58 downregulation) in the M/V comparison. Conclusion: The current results highlight the pathogenesis of m6A methylation in obstructive and reflux uropathy.

Lupus podocytopathy and antiphospholipid syndrome in a child with SLE: A case report and literature review.

Lupus podocytopathy is a glomerular lesion in systemic lupus erythematosus (SLE) characterized by diffuse podocyte foot process effacement (FPE) without immune complex (IC) deposition or with only mesangial IC deposition. It is rarely seen in children with SLE. A 13-year-old girl met the 2019 European League Against Rheumatism (EULAR)/ American College of Rheumatology (ACR) Classification Criteria for SLE based on positive ANA; facial rash; thrombocytopenia; proteinuria; and positive antiphospholipid (aPL) antibodies, including lupus anticoagulant (LAC), anti-ß2 glycoprotein-I antibody (anti-ß2GPI), and anti-cardiolipin antibody (aCL). The renal lesion was characterized by 3+ proteinuria, a 4.2 mg/mg spot (random) urine protein to creatinine ratio, and hypoalbuminemia (26.2 g/l) at the beginning of the disease. Kidney biopsy findings displayed negative immunofluorescence (IF) for immunoglobulin A (IgA), IgM, fibrinogen (Fb), C3, and C1q, except faint IgG; a normal glomerular appearance under a light microscope; and diffuse podocyte foot process effacement (FPE) in the absence of subepithelial or subendothelial deposition by electron microscopy (EM). Histopathology of the epidermis and dermis of the pinna revealed a hyaline thrombus in small vessels. The patient met the APS classification criteria based on microvascular thrombogenesis and persistently positive aPL antibodies. She responded to a combination of glucocorticoids and immunosuppressive agents. Our study reinforces the need to consider the potential cooccurrence of LP and APS. Clinicians should be aware of the potential presence of APS in patients with a diagnosis of LP presenting with NS and positivity for aPL antibodies, especially triple aPL antibodies (LCA, anti-ß2GPI, and aCL).

PHOX2B as a Reliable Marker for Neuroblastoma in Tissue and Cytology Specimens.

To investigate the diagnostic utility of immunohistochemistry for paired-like homeobox 2B (PHOX2B) expression in neuroblastomas (NBs) and tumors that mimic them, tissue samples (n = 229) from 157 cases of NB, 210 central nervous system tumors, and 170 extracranial non-NB solid tumors (n = 170) were immunostained for PHOX2B. Additionally, PHOX2B expression in 67 body fluid cytology specimens was analyzed. In tissue specimens, PHOX2B expression was positive in NBs, pheochromocytomas, and paragangliomas but negative in all of the other tumors evaluated. PHOX2B was detected by immunohistochemistry in 5 NB cytology specimens; all of the others were negative. These results suggest that PHOX2B may be a sensitive and specific immunohistochemical marker for the pathological diagnosis and differential diagnosis of NB in both tissue and cytology specimens.

Characteristics and outcomes of glomerulonephritis with membranoproliferative pattern in children.

BACKGROUND: Membranoproliferative glomerulonephritis (MPGN) is a rare histopathologic pattern of glomerular injury with limited studies in pediatric patients. Characteristics and outcomes of children with MPGN have also remained to be further explored. METHODS: We retrospectively reviewed the clinicopathological features, genetic findings, treatments and outcomes in 17 pediatric patients pathologically diagnosed with MPGN from 2007 to 2020 in the Children's National Medical Center in China. RESULTS: Median age at disease onset was 9.9 years (IQR, 5.6-11.9 years). Most of the patients (12/17) had nephrotic range of proteinuria, and nephritic-nephrotic syndrome was the most common clinical presentation (35.2%). Secondary causes were identified in eight patients including hepatitis B virus (HBV) infection (n=4), methylmalonic acidemia (MMA, n=2), rheumatoid arthritis (RA, n=1) and Aymé-Gripp Syndrome (n=1). The nine patients with primary MPGN were further identified as immune-complex mediated MPGN (n=8), and unclassifiable MPGN (U-MGPN, n=1). Genetic analyses identified pathogenic variants of MMACHC gene in two cases of MMA and established the diagnosis for Aymé-Gripp syndrome in one case with a de novo variant of MAF gene. Comparing study between the complete or partial remission group (n=8) and non-response group (n=9) showed a significant difference in the timing of renal biopsy (P<0.05). Normal renal function was preserved in ten patients at the last follow-up. Two patients developed into end-stage renal disease (ESRD). CONCLUSIONS: Children with MPGN pattern present heterogenous clinical features. Genetic detection helps to explore underlying causes of MPGN. Early identification of the primary or secondary causes of MPGN in children is vital.

Glycogen storage disease type VI can progress to cirrhosis: ten Chinese patients with GSD VI and a literature review.

Objectives The aim of our study is to systematically describe the genotypic and phenotypic spectrum of Glycogen storage disease type VI (GSD VI), especially in Chinses population.  Methods We retrospectively analyzed ten Chinese children diagnosed as having GSD VI confirmed by next generation sequencing in Children's Hospital of Fudan University and Jinshan Hospital of Fudan University. We described the genotypic and phenotypic spectrum of GSD VI through the clinical and genetic data we collected. Moreover, we conducted a literature review, and we compared the genotypic and phenotypic spectrum of GSD VI between Chinese population and non Chinese population.  Results For the first time, we found that four Chinese patients showed cirrhosis in liver biopsy characterized by the formation of regenerative nodules. In addition, c.772+1G>A and c.1900G>C, p.(Asp634His) were recurrent in three Chinese families and four European families respectively indicating that the genotypic spectrum of PYGL gene may vary among the population. Furthermore, we identified seven novel variants in PYGL gene.  Conclusions Our study enriched the genotypic and phenotypic spectrum of GSD VI, and provided a new clue for management of GSD VI.