Pediatric Acute Liver Failure in Sickle Cell Disease.

Introduction: Sickle cell intrahepatic cholestasis (SCIC) is one of the rarest and the most severe acute hepatic manifestations of sickle cell disease (SCD) and it can rapidly progress to acute liver failure. It is associated with a high mortality rate, demanding prompt recognition and management. Case Presentation: We report a case of a 7-year-old boy with a history of homozygous HbS SCD who presented to the emergency department with fever, increasing abdominal pain, and jaundice. His course was complicated by acute liver injury (AST 9,472 IU/L, ALT 2,683 IU/L, total bilirubin 15.4 mg/dL; conjugated bilirubin 8.69 mg/dL, hypoalbuminemia 2.6 g/dL, and persistent hypoglycemia), with acute liver failure (coagulopathy not corrected by vitamin K administration with INR 3.26, decreased factors V 10% and VII 28%, and West Haven grade I hepatic encephalopathy associated with mild hyperammonemia of 71 µmol/L). After excluding other causes of acute liver failure, the patient was diagnosed as having SCIC and was successfully treated with manual exchange transfusion. Conclusion: This case reinforces that exchange transfusion is an effective treatment for SCIC and that it should be introduced promptly to prevent fulminant and potentially fatal liver failure.

Introdução: A colestase intra-hepática falciforme (CIHF) é uma das manifestações hepáticas agudas mais raras e graves da doença de células falciformes (DCF), que pode progredir rapidamente para falência hepática aguda. Associa-se a uma elevada taxa de mortalidade, que exige identificação e intervenção imediatas. Caso clínico: Descreve-se o caso de um rapaz de 7 anos com DCF, homozigótico para a HbS, que recorreu ao serviço de urgência por febre, dor abdominal de agravamento progressivo e icterícia. Verificou-se evolução para lesão hepática aguda (AST 9,472 UI/L, ALT 2,683 UI/L, bilirrubina total 15.4 mg/dL; bilirrubina conjugada 8.69 mg/dL, hipoalbuminemia 2.6 g/dL, hipoglicemia persistente), com falência hepática aguda (coagulopatia não corrigida por administração de vitamina K com INR 3.26, diminuição dos fatores V 10% e VII 28%, assim como encefalopatia grau I (critérios de West Haven) e hiperamoniemia ligeira 71 µmol/L). Após exclusão de outras etiologias de falência hepática aguda, o doente foi diagnosticado com CIHF e realizada exsanguineo-transfusão manual, com sucesso. Discussão/Conclusão: Este caso reforça que a exsanguineotransfusão é uma terapêutica eficaz na CIHF, que deve ser instituída precocemente para prevenir falência hepática fulminante e potencialmente fatal.

Interplay between TERT promoter mutations and methylation culminates in chromatin accessibility and TERT expression.

The telomerase reverse transcriptase (TERT) gene is responsible for telomere maintenance in germline and stem cells, and is re-expressed in 90% of human cancers. CpG methylation in the TERT promoter (TERTp) was correlated with TERT mRNA expression. Furthermore, two hotspot mutations in TERTp, dubbed C228T and C250T, have been revealed to facilitate binding of transcription factor ETS/TCF and subsequent TERT expression. This study aimed to elucidate the combined contribution of epigenetic (promoter methylation and chromatin accessibility) and genetic (promoter mutations) mechanisms in regulating TERT gene expression in healthy skin samples and in melanoma cell lines (n = 61). We unexpectedly observed that the methylation of TERTp was as high in a subset of healthy skin cells, mainly keratinocytes, as in cutaneous melanoma cell lines. In spite of the high promoter methylation fraction in wild-type (WT) samples, TERT mRNA was only expressed in the melanoma cell lines with either high methylation or intermediate methylation in combination with TERT mutations. TERTp methylation was positively correlated with chromatin accessibility and TERT mRNA expression in 8 melanoma cell lines. Cooperation between epigenetic and genetic mechanisms were best observed in heterozygous mutant cell lines as chromosome accessibility preferentially concerned the mutant allele. Combined, these results suggest a complex model in which TERT expression requires either a widely open chromatin state in TERTp-WT samples due to high methylation throughout the promoter or a combination of moderate methylation fraction/chromatin accessibility in the presence of the C228T or C250T mutations.

Genome-wide analysis of constitutional DNA methylation in familial melanoma.

BACKGROUND: Heritable epigenetic alterations have been proposed as an explanation for familial clustering of melanoma. Here we performed genome-wide DNA methylation analysis on affected family members not carrying pathogenic variants in established melanoma susceptibility genes, compared with healthy volunteers. RESULTS: All melanoma susceptibility genes showed the absence of epimutations in familial melanoma patients, and no loss of imprinting was detected. Unbiased genome-wide DNA methylation analysis revealed significantly different levels of methylation in single CpG sites. The methylation level differences were small and did not affect reported tumour predisposition genes. CONCLUSION: Our results provide no support for heritable epimutations as a cause of familial melanoma.

Genome-wide characterization of 5-hydoxymethylcytosine in melanoma reveals major differences with nevus.

Melanoma demonstrates altered patterns of DNA methylation that are associated with genetic instability and transcriptional repression of numerous genes. Active DNA demethylation is mediated by TET enzymes that catalyze conversion of 5-methylcytosine (mC) to 5-hydroxymethylcytosine (hmC). Loss of hmC occurs in melanoma and correlates with disease progression. Here we analyzed the genomic distribution of hmC along with mC in nevus and melanoma using oxidative bisulfite chemistry combined with high-density arrays. HmC was enriched relative to mC at enhancers, 5'UTR regions and CpG shores in nevus and melanoma samples, pointing to specific TET enzyme activity. The proportion of interrogated CpG sites with high hmC levels was lower in melanoma (0.54%) than in nevus (2.0%). Depletion of hmC in melanoma was evident across all chromosomes and intragenic regions, being more pronounced in metastatic than in non-metastatic tumors. The patterns of hmC distribution in melanoma samples differed significantly from those in nevus samples, exceeding differences in mC patterns. We identified specific CpG sites and regions with significantly lower hmC levels in melanoma than in nevus that might serve as diagnostic markers. Differentially hydroxymethylated regions localized to cancer-related genes, including the PTEN gene promoter, suggesting that deregulated DNA hydroxymethylation may contribute to melanoma pathogenesis.

A novel germline variant in the DOT1L gene co-segregating in a Dutch family with a history of melanoma.

A proportion of patients diagnosed with melanoma has a positive family history. Despite increasing knowledge on the genes responsible for familial clustering, the genetic basis in the majority of the families with an inherited predisposition to melanoma remains to be clarified. To identify novel melanoma-susceptibility genes, we applied whole-exome sequencing on DNA from two members of a family with four melanoma cases, not explained by established high penetrance melanoma-susceptibility genes. Whole-exome sequencing identified 10 rare, co-segregating, predicted deleterious missense gene variants. Subsequent co-segregation analysis revealed that only variants in the DOT1L (R409H) and the SLCO4C1 (P597A) genes were present in the other two affected members of this family. DOT1L is a methyltransferase that methylates histone H3 lysine 79 (H3K79). It is involved in maintenance of genomic stability, since mutations in the DOT1L gene have been previously reported to compromise the removal of ultraviolet photoproducts in ultraviolet-irradiated melanocytes, thereby enhancing malignant transformation. We hypothesized that the presence of DOT1L R409H variant might be associated with an increased risk of melanoma, since we found co-segregation of the DOT1L mutation in all four melanoma-affected family members. However, this missense variant did neither lead to detectable loss-of-heterozygosity nor reduction of histone methyltransferase activity in melanoma samples from mutation carriers nor altered ultraviolet-survival of mouse embryonic stem cells containing an engineered homozygous DOT1L R409H mutation. Although functional analysis of this rare co-segregating variant did not reveal compromised histone methyltransferase activity and ultraviolet exposure sensitivity, the role of DOT1L as melanoma susceptibility gene deserves further study.

Sleep habits in infants: the role of maternal education.

OBJECTIVE: Sleep disturbances are frequent in infants. Early development of sleep routines has a positive effect on sleep quality. The objective of this study was to assess the impact of maternal education on the development of infants' sleep habits (SHs). METHODS: This was an experimental, longitudinal study. Postnatal mothers were allocated into two groups: to receive (intervention group, IG), or not receive (control group, CG) information on sleep hygiene. Individual 15-min sessions were provided and a leaflet was handed to the IG. A questionnaire on infants' SHs was applied by telephone/e-mail at 1, 2, 4, and 6 months of age. RESULTS: At least three questionnaires were answered by 314 mothers. Results were adjusted for maternal age, education, and race. In the IG, infants acquired more independent sleep habits, an effect still present at six months; slept more frequently in their own beds; adjusted odds ratio (ORadj) 3.8, 95% confidence interval (CI) (1.1-13.5); fell asleep more frequently alone (ORadj, 4.29; 95% CI, 2.4-7.6); fell asleep more frequently in their own beds (ORadj, 6.1; 95% CI, 3.5-10.6) and needed less breast/bottle feeding to fall asleep (ORadj, 2.68; 95% CI, 1.5-4.6). The autonomy was greater in IG infants after night awakenings; also until six months they went back to sleep more frequently alone (ORadj, 3.88; 95% CI, 2-7.5) and needed less breast/bottle feeding (ORadj, 2.35; 95% CI, 1.3-4.3). No differences were found regarding the need for light, television or other routines to fall asleep or after night awakenings. CONCLUSION: Maternal education is positively associated with the adoption of autonomous SHs in infants. Early maternal education is an adequate prevention strategy to be considered in neonatal care.

Ptosis, miosis and cats.

Horner's syndrome (HS) is caused by a disruption in the oculosympathetic pathway. Both congenital and acquired HS are unusual in children. Acquired HS can be caused by trauma, surgical intervention, tumours, vascular malformations or infection.We describe the case of a 6-year-old boy who was brought to our emergency department with ptosis, miosis, painful cervical lymphadenopathy and a cat scratch on a hand. The diagnosis of a cat scratch disease was confirmed by serology. A full recovery was observed on antibiotic treatment and cervical lymphadenomegaly reduction 3 weeks later.

[Infectious Mononucleosis and Cholestatic Hepatitis: A Rare Association]. / Mononucleose Infeciosa e Hepatite Colestática: Uma Associação Rara.

Infectious mononucleosis is one of the major clinical manifestations of Epstein-Barr virus infection. In this syndrome, elevation of liver transaminase levels is common but cholestasis is rare, with few cases described in the literature. We present the case of a 14-year-old female adolescent, admitted to the Emergency Room with fever, odynophagia and cervical adenomegaly. She was treated with amoxicillin and two days later he presented with jaundice. The analytical evaluation was compatible with cholestatic hepatitis and abdominal ultrasound revealed hepatosplenomegaly without dilatation of the bile ducts. The diagnosis of Epstein-Barr virus infection was confirmed by the presence of serological markers. This case aims to raise awareness of a rare manifestation of a common infectious agent and, consequently, to the inclusion of acute Epstein-Barr virus infection in the differential diagnosis of pediatric cholestatic hepatitis.

A mononucleose infeciosa é uma das principais manifestações clínicas da infeção pelo vírus Epstein-Barr. Nesta síndrome, a elevação das aminotransferases é comum mas a colestase é rara, havendo poucos casos descritos na literatura. Adolescente, 14 anos, sexo feminino, admitida no serviço de urgência por febre, odinofagia e adenomegália cervical. Iniciou tratamento com amoxicilina e dois dias depois iniciou icterícia. A avaliação analítica foi compatível com hepatite colestática e a ecografia abdominal revelou hepatoesplenomegália, sem dilatação das vias bilares. O diagnóstico de infeção pelo vírus Epstein-Barr foi confirmado pela presença de marcadores serológicos. Este caso pretende alertar para uma manifestação rara de um agente infecioso comum e, consequentemente, para a inclusão da infeção aguda a vírus Epstein-Barr no diagnóstico diferencial de hepatite colestática na idade pediátrica.

pmTOR is a marker of aggressiveness in papillary thyroid carcinomas.

BACKGROUND: Activation of the mTOR pathway has been observed in thyroid cancer, but the biologic consequences regarding tumor behavior and patient prognosis remain poorly explored. METHODS: We aimed to evaluate the associations of the mTOR pathway with clinicopathologic and molecular features and prognosis through the immunocharacterization of pmTOR and pS6 expression (as readouts of the pathway) in a series of 191 papillary thyroid carcinomas. RESULTS: pmTOR expression was associated with distant metastases (P = .05) and persistence of disease (P = .05). Cases with greater expression of pmTOR were submitted to more 131I treatments (r[102] = 0.2; P = .02) and a greater cumulative dose of radioactive iodine (r[100] = 0.3; P = .01). Positive pmTOR expression showed to be an independent risk factor for distant metastases (odds ratio = 18.2; 95% confidence interval 2.1-157.9; P = .01). In contrast, pS6 expression was associated with absence of extrathyroid extension (P = .001), well-defined tumor margins (P = .05), and wild-type BRAF status (P = .01). There was no correlation between the expression of pmTOR and pS6 expression (r[140] = 0.1; P = .3). CONCLUSION: pmTOR expression is an indicator of aggressive, metastatic papillary thyroid carcinoma, being possibly implicated in refractoriness to therapy, while pS6 expression is associated with less aggressive pathologic features. Further studies are needed to understand better the biologic consequences of activation of the mTOR pathway in the behavior of thyroid cancer, namely the contribution of other pmTOR downstream effectors.

Poorly Differentiated and Undifferentiated Thyroid Carcinomas.

Thyroid cancer is the most common endocrine malignancy and its incidence goes on increasing worldwide. The majority of thyroid tumours comprise well-differentiated (papillary and follicular) thyroid carcinomas that usually carry an excellent prognosis, while a minority progress to poorly differentiated carcinoma (PDTC) and, ultimately, to the highly aggressive and lethal undifferentiated carcinoma (UTC). Recently, some major advances have been made on the histologic and imunohistochemical identification, as well as on the molecular characterization of PDTC and UTC. In this review we summarize the most recent immunohistochemical and molecular findings in PDTC and UTC, giving a particular emphasis to the diagnostic and prognostic meaning of the genetic alterations.

TERT promoter mutations are a major indicator of poor outcome in differentiated thyroid carcinomas.

CONTEXT: Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers. OBJECTIVES: We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs). DESIGN: This was a retrospective observational study. SETTING AND PATIENTS: We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (±SD) was 7.8 ± 5.8 years. MAIN OUTCOME MEASURES: Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality. RESULTS: TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01-53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36-415.76; P = .03) in PTCs. CONCLUSIONS: TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.