Cardiovascular Mortality after Venous Thromboembolism: A Meta-Analysis of Prospective Cohort Studies.

Many studies from current literature show that cardiovascular diseases in patients with venous thromboembolism (VTE) are more frequent than in the general population without VTE. However, data summarizing the impact of cardiovascular diseases on mortality of patients with VTE are lacking. In this systematic review and meta-analysis, we aimed to determine the frequency and incidence rate of cardiovascular death in patients with VTE. MEDLINE and EMBASE were searched from January 1, 2000 to February 28, 2021. Eligible studies were observational prospective cohort studies including patients with VTE and reporting all causes of death. Cardiovascular death was defined as deaths that result from new or recurrent pulmonary embolism, death due to acute myocardial infarction, sudden cardiac death or heart failure, death due to stroke, death due to cardiovascular procedures or hemorrhage, death due to ruptured aortic aneurysm or aortic dissection and death due to other cardiovascular causes. Random-effect models meta-analysis served to determine all pooled effect size of interest with their 95% confidence interval (CI). Thirteen observational studies enrolling 22,251 patients were identified and included. The mean/median age varied between 49 and 75 years. The proportion of men ranged from 38.3 to 53.2%. The overall pooled frequency of cardiovascular death in patients with VTE was 3.9% (95% CI: 2.5-5.6%), while the overall pooled frequency of all-cause mortality was 12.0% (95% CI: 9.1-15.4%). The pooled proportion of cardiovascular death among all causes of deaths in patients with VTE was 35.2% (95% CI: 22.2-49.3%). The pooled incidence rate of cardiovascular death was 1.92 per 100 patient-years (95% CI: 0-4.1). The frequency of cardiovascular death in patients with VTE was significantly higher than in patients without VTE (risk ratio: 3.85, 95% CI: 2.75-5.39). Based on this updated meta-analysis from 13 prospective cohort studies, cardiovascular death in patients with VTE is more frequent than in the general population without VTE.

The nutritional behavior of children with autism spectrum disorder, parental feeding styles, and anthropometric measurements.

BACKGROUND: Although autism spectrum disorder (ASD) is known to include problems relating to nutrition, information about nutritional behavior, caregiver feeding styles, and anthropometric measurements is still limited. AIMS: We aimed to assess the nutritional behavior, anthropometric measurements, and caregiver feeding styles of children with ASD. METHOD: One hundred and four children with ASD and 100 controls were enrolled in the study. Children's weight and height were measured and recorded by the researchers. The Children's Eating Behavior Questionnaire, Parental Feeding Style Questionnaire, Development Assessment Form, and Sociodemographic Data Form were conducted by their caregivers. RESULTS: Children with ASD were difficult to feed as babies, experienced more problems in the transition to supplementary food, were more selective about food, and were fed diets with a more limited variety than the control group. The BMI z-scores for children with ASD were higher than those for children without ASD, while their height z-scores were lower. Children with ASD displayed more responsiveness to food, emotional overeating, enjoyment of food, desire for drinks, emotional undereating, and food selectivity behaviors, while the parents of these children were found to use more emotional feeding, instrumental feeding, and tolerance-controlled feeding styles than the parents of the controls. CONCLUSIONS: Children with ASD are more selective about foods and have greater difficulty in switching to supplementary food. The BMI-z score for children with ASD is higher and the height-z score is lower. Children with ASD have different eating and feeding styles compared to children in the control group.

Evaluation of Blood Zonulin Levels, Inflammatory Processes and Neuronal Changes in Children with Autism Spectrum Disorder.

BACKGROUND: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by symptoms such as limited, and repetitive behavior patterns and disordered social interaction and communication. The etiology of Autism Spectrum Disorder (ASD) is not clearly known, it has been emphasized that the immune-inflammatory system may also play a role in this disease. This study aimed to evaluate in intestinal permeability, food antigen-antibody levels, inflammatory processes, and neuron damage in patients with ASD. SUBJECTS AND METHODS: Thirty-five children between the ages of 3-12 with ASD and 35 controls were included in the study. Both participants' height and weight were measured, and the parents filled the Socio-demographic Data and the Gastrointestinal Systems (GIS) Symptoms Form. Venous blood samples were collected, and serum zonulin, anti-gliadin Ig A and Ig G, IL6, TNF-alpha, TGF- ß, S100B, and NSE levels were measured by ELISA. RESULTS: Serum zonulin levels in the ASD group were found to be significantly lower. IL-6 and TGF-ß were found to be significantly higher in the ASD group. There was no difference between the two groups in terms of serum anti-gliadin Ig A and Ig G and TNF-alpha values. Also, GIS symptoms, NSE and S100B levels were found similar between two groups. CONCLUSIONS: Although findings showing low zonulin levels and increased inflammatory processes in ASD were found in this study, no difference was found in the parameters of brain damage. The findings show that intestinal permeability does not decrease in ASD and that inflammatory processes may play a role in ASD.

Pneumatosis cystoides intestinalis: A rare complication after hematopoietic stem cell transplantation.

BACKGROUND: Pneumatosis cystoides intestinalis (PCI) is a disorder in which widespread air sacs are present in mucosa, submucosa, subserosa, and intraabdominal area of the intestinal wall. It has a heterogeneous clinical presentation as a rare complication of intestinal graft-versus-host disease (GVHD). Computed tomography is the preferred imaging method for the diagnosis. Since the air sacs could be ruptured spontaneously, the presence of free air in the peritoneal cavity does not confirm intestinal perforation. The conservative treatment approach is sufficient in cases that do not require urgent surgical intervention, such as perforation or obstruction. CASE: Here, we present a 2.5-year-old patient diagnosed with primary hemophagocytic lymphohistiocytosis (pHLH), who underwent allogeneic hematopoietic stem cell transplantation from a matched unrelated donor (MUD) and developed PCI secondary to intestinal GVHD 14th months after HSCT. CONCLUSIONS: Pneumatosis cystoides intestinalis, which is a rare complication, should be kept in mind, especially in patients with intestinal GVHD and receiving intensive immunosuppressive, octreotide, and steroid treatment after HSCT.

Anxiety, depression and post-traumatic stress disorder symptoms in adolescents during the COVID-19 outbreak and associated factors.

INTRODUCTION: Outbreaks of infectious diseases have negative effects on mental health. Currently, there is very little information about the psychological effects of the COVID-19 pandemic on adolescents and associated factors affecting their mental health. The aim of the present study is to determine the severity of anxiety, depression and post-traumatic stress disorder (PTSD) symptoms in adolescents during the COVID-19 outbreak, and to investigate the associated factors with these symptoms. METHODS: The present study was conducted with a total of 447 adolescents. Psychiatric symptoms were evaluated by the use of DSM-5 Level 2 Anxiety Scale, DSM-5 Level 2 Depression Scale and National Stressful Events Survey PTSD Short Scale. The association between age, gender, residential area, presence of COVID-19 in the participant, presence of COVID-19 in the family or environment and psychiatric symptoms were evaluated with linear regression analysis. RESULTS: The mean age of participants was 15.06, and 38.3% of the participants were men and 61.7% were women. The rate of participants with moderate or high levels of anxiety, depression and PTSD symptoms was 28%, 37.6% and 28.5%, respectively. High age and living in an urban area were associated with increased anxiety, depression and PTSD symptoms. In addition, female gender was associated with increased depression symptoms, and the presence of COVID-19 in the family or environment was associated with increased anxiety symptoms. CONCLUSION: The present study shows that adolescents have serious levels of anxiety, depression and PTSD symptoms during the COVID-19 pandemic. These results emphasise the need for mental health interventions that are appropriate for the characteristics of this age group.

Autoimmune atrophic gastritis: The role of Helicobacter pylori infection in children.

BACKGROUND: Autoimmune atrophic gastritis (AIG) is very rare in children. Despite a better understanding of histopathologic changes and serological markers in this disease, underlying etiopathogenic mechanisms and the effect of Helicobacter pylori (H pylori) infection are not well known. We aimed to investigate the relation between AIG and H pylori infection in children. MATERIALS AND METHODS: We evaluated the presence of AIG and H pylori infection in fifty-three patients with positive antiparietal cell antibody (APCA). Demographic data, clinical symptoms, laboratory and endoscopic findings, histopathology, and presence of H pylori were recorded. RESULTS: The children were aged between 5 and 18 years, and 28 (52.8%) of them were male. Mean age was 14.7 ± 2.6 years (median: 15.3; min-max: 5.2-18), and 10 (18.8%) of them had AIG confirmed by histopathology. In the AIG group, the duration of vitamin B12 deficiency was longer (P = .022), hemoglobin levels were lower (P = .018), and APCA (P = .039) and gastrin (P = .002) levels were higher than those in the non-AIG group. Endoscopic findings were similar between the two groups. Intestinal metaplasia was higher (P = .018) in the AIG group. None of the patients in the AIG group had H pylori infection (P = .004). One patient in the AIG group had enterochromaffin-like cell hyperplasia. CONCLUSIONS: Our results show that, in children, H pylori infection may not play a role in AIG. AIG could be associated with vitamin B12 deficiency, iron deficiency, and APCA positivity in children. APCA and gastrin levels should be investigated for the early diagnosis of AIG and intestinal metaplasia.

Targeting spare CC chemokine receptor 5 (CCR5) as a principle to inhibit HIV-1 entry.

CCR5 binds the chemokines CCL3, CCL4, and CCL5 and is the major coreceptor for HIV-1 entry into target cells. Chemokines are supposed to form a natural barrier against human immunodeficiency virus, type 1 (HIV-1) infection. However, we showed that their antiviral activity is limited by CCR5 adopting low-chemokine affinity conformations at the cell surface. Here, we investigated whether a pool of CCR5 that is not stabilized by chemokines could represent a target for inhibiting HIV infection. We exploited the characteristics of the chemokine analog PSC-RANTES (N-α-(n-nonanoyl)-des-Ser(1)-[l-thioprolyl(2), l-cyclohexylglycyl(3)]-RANTES(4-68)), which displays potent anti-HIV-1 activity. We show that native chemokines fail to prevent high-affinity binding of PSC-RANTES, analog-mediated calcium release (in desensitization assays), and analog-mediated CCR5 internalization. These results indicate that a pool of spare CCR5 may bind PSC-RANTES but not native chemokines. Improved recognition of CCR5 by PSC-RANTES may explain why the analog promotes higher amounts of ß-arrestin 2·CCR5 complexes, thereby increasing CCR5 down-regulation and HIV-1 inhibition. Together, these results highlight that spare CCR5, which might permit HIV-1 to escape from chemokines, should be targeted for efficient viral blockade.

Yield of coeliac screening in abdominal pain-associated functional gastrointestinal system disorders.

AIM: Chronic abdominal pain (CAP) in childhood is common and in the majority functional. While CAP is one of the complaints of coeliac disease (CD), whether CAP as a sole complaint is indicative of CD is unclear. Our aim was to evaluate the relationship between CAP and CD. METHODS: The study was conducted on 1047 children (61.1% female, mean age 9.6 ± 4.1 years) with CAP. Patients were evaluated according to the Rome III criteria. Patients with alarm symptoms and conditions known to be associated with CD were excluded. Patients were screened for CD using a rapid tissue transglutaminase (tTG) test; positive cases were tested by tTG ELISA, and duodenal biopsies were obtained if tTG was above the normal limit. RESULTS: Functional dyspepsia (FD), irritable bowel syndrome (IBS) and functional abdominal pain (FAP) were diagnosed in 384 (36.7%), 274 (26.2%) and 389 (37.2%) patients, respectively. In 13 patients, the tTG rapid test was positive; 10 were also positive for tTG by ELISA and histopathological evaluations diagnosed CD in all 10 patients. The overall prevalence of CD was 0.95% (2.2%, 0.5% and 0.5% in patients with IBS, FD and FAP, respectively). The prevalence of CD in patients with IBS was higher than expected but with borderline statistical significance (P = 0.053). CONCLUSIONS: CD is found as common in children with FD and FAP as in the general population. CD was more commonly diagnosed in IBS patients with borderline statistical significance. We suggest that particular attention be paid to children with IBS.

Early-onset inflammatory bowel disease and common variable immunodeficiency-like disease caused by IL-21 deficiency.

BACKGROUND: Alterations of immune homeostasis in the gut can result in development of inflammatory bowel disease (IBD). Recently, Mendelian forms of IBD have been discovered, as exemplified by deficiency of IL-10 or its receptor subunits. In addition, other types of primary immunodeficiency disorders might be associated with intestinal inflammation as one of their leading clinical presentations. OBJECTIVE: We investigated a large consanguineous family with 3 children who presented with early-onset IBD within the first year of life, leading to death in infancy in 2 of them. METHODS: Homozygosity mapping combined with exome sequencing was performed to identify the molecular cause of the disorder. Functional experiments were performed to assess the effect of IL-21 on the immune system. RESULTS: A homozygous mutation in IL21 was discovered that showed perfect segregation with the disease. Deficiency of IL-21 resulted in reduced numbers of circulating CD19(+) B cells, including IgM(+) naive and class-switched IgG memory B cells, with a concomitant increase in transitional B-cell numbers. In vitro assays demonstrated that mutant IL-21(Leu49Pro) did not induce signal transducer and activator of transcription 3 phosphorylation and immunoglobulin class-switch recombination. CONCLUSION: Our study uncovers IL-21 deficiency as a novel cause of early-onset IBD in human subjects accompanied by defects in B-cell development similar to those found in patients with common variable immunodeficiency. IBD might mask an underlying primary immunodeficiency, as illustrated here with IL-21 deficiency.

Wilms' tumor: a 24-year retrospective study from a single center.

Medical records of 71 children with Wilms' tumor at Sisli Etfal Education and Research Hospital between 1990 and 2014 were reviewed. Mean age at diagnosis was 3.11 years (2 days-7 years). Male to female ratio was M/F = 6/10. The incidence of associated anomaly was 16.9%. Clinical manifestations included abdominal mass (89%), hematuria (30%), hypertansion (25%), abdominal pain (15%), fever (5%), restlessness (2%), weight loss (2%), varicocele (1%). Ultrasound (USG) was the most often initial study in a child presenting with abdominal mass. Doppler USG was also made to evaluate the inferior vena cava (IVC) for the presence of tumor extension in children with renal mass. The left kidney was affected in 33 patients (46.5%), the right was affected in 31 patients (43.7%). Two patients was extrarenal (2.8%). And 5 patients (7.04%) were bilateral on the presentation. Preoperative chemotheraphy was done in 14 cases. In 63 patients with unilateral Wilm tm, unilateral radical nefrectomy is performed. In one patient with solitary kidney, nephron sparing surgery (NSS) is performed. In 3 patients with bilateral tm NSS is performed and in 2 patients with bilateral Wilms' tm NSS is performed in one side and nefrectomy on the other side. Out of 71 Wilms tumor (WT) patients, 17 of them has been out of our follow. And 4 of them are died. Ten of them has metastases. Forty children are under follow with no metastases. Patients with WT needs a multimodal, multidisiplinary treatment with the cooperation of pediatric oncologist and pediatric surgeon and needs close follow-up.

Vestibular Evaluation of Children Diagnosed with Specific Learning Disorder.

Objective: The aim of this study was to determine the vestibular function of children diagnosed with specific learning disorders (SLD). Methods: This study was conducted with 30 children diagnosed with SLD and 30 healthy children matched for age and sex, and vestibular tests were applied. Results: Optokinetic and head shake test values in videonystagmography subtests were found to be pathological in the study group, and the lateral asymmetry value in video head impulse test (v-HIT) was found to be significantly higher in the study group. Also, a significant difference was found in the N1 latency, P1-N1 interlatency, P1-N1 amplitude values in the cervical vestibular evoked myogenic potential test, and asymmetry values in the ocular vestibular evoked myogenic potential test. Conclusion: The current study showed that vestibular functions may differ from normal in SLD patients and that vestibular dysfunction may play a role in symptoms such as postural instability, balance, and gross and fine motor disorders that are frequently observed in these children.

The relationship between smoking, alcohol, and substance abuse and psychiatric diseases among adolescents treated in a child and adolescent psychiatry inpatient unit.

BACKGROUND: This study aimed to investigate the prevalence of smoking, alcohol, and substance abuse disorders among adolescents hospitalized in a university hospital child and adolescent psychiatry inpatient unit with different diagnoses, and to determine the rates of these disorders according to the mental illness diagnosis groups. METHODS: The study was conducted with 346 adolescents aged 12-18 who had been hospitalized with any psychiatric diagnosis between September 2016 and January 2020 in the child and adolescent psychiatry inpatient unit. The study considered the psychiatric diagnoses, based on the results of the DSM-5-based psychiatric interview; sociodemographic and clinical characteristics; the psychopathology history of first-degree relatives; comorbidities; length of hospital stay; income levels, and smoking, alcohol, and substance abuse. RESULTS: Twenty-four percent (n=83) of the participants had been smoking for 18 months or longer, 6.9% (n=24) were using alcohol, and 1% (n=28) were substance abusers. When the diagnosis distributions were examined, smoking was found to be higher in those with depressive disorders and trauma and related disorders, while smoking, alcohol, and substance use were found to be higher in the disruptive behavior disorder group. Smoking was found to be significantly lower in the obsessive-compulsive disorder group. CONCLUSIONS: Smoking, alcohol, and substance use among inpatient children and adolescents may worsen their existing psychopathology, so health professionals working in this field should consider this situation.

Celiac crisis with thrombocytopenia and coagulopathy in a child.

BACKGROUND: Celiac disease rarely presents with edema, hypoalbuminemia, acute metabolic deterioration, and electrolyte imbalances. This life-threatening condition is defined as a celiac crisis and may mimic disorders with metabolic derangement and sepsis. The crisis may present at onset or develop in celiac disease patients with poor compliance to a gluten-free diet. The fluid resuscitation and replacement of electrolyte deficits are life-saving modalities. CASE: A 14-month-old girl was admitted with fever, lethargy, severe dehydration, edema, hypotension, and commenced sepsis therapy. However, the patient had a growth delay and loss of weight with diarrhea and delayed motor skills. On admission, laboratory evaluation showed anemia, coagulopathy, hypoalbuminemia, electrolyte disturbances, and metabolic acidosis and developed thrombocytopenia during follow-up. The celiac serological tests and upper gastrointestinal endoscopic duodenal mucosa appearance, and duodenum histopathology findings suggested celiac disease. CONCLUSIONS: This case highlights that a celiac patient may present with a severe illness like sepsis and may be associated with cytopenia and coagulopathy in the celiac crisis.

UNC45A deficiency causes microvillus inclusion disease-like phenotype by impairing myosin VB-dependent apical trafficking.

Variants in the UNC45A cochaperone have been recently associated with a syndrome combining diarrhea, cholestasis, deafness, and bone fragility. Yet the mechanism underlying intestinal failure in UNC45A deficiency remains unclear. Here, biallelic variants in UNC45A were identified by next-generation sequencing in 6 patients with congenital diarrhea. Corroborating in silico prediction, variants either abolished UNC45A expression or altered protein conformation. Myosin VB was identified by mass spectrometry as client of the UNC45A chaperone and was found misfolded in UNC45AKO Caco-2 cells. In keeping with impaired myosin VB function, UNC45AKO Caco-2 cells showed abnormal epithelial morphogenesis that was restored by full-length UNC45A, but not by mutant alleles. Patients and UNC45AKO 3D organoids displayed altered luminal development and microvillus inclusions, while 2D cultures revealed Rab11 and apical transporter mislocalization as well as sparse and disorganized microvilli. All those features resembled the subcellular abnormalities observed in duodenal biopsies from patients with microvillus inclusion disease. Finally, microvillus inclusions and shortened microvilli were evidenced in enterocytes from unc45a-deficient zebrafish. Taken together, our results provide evidence that UNC45A plays an essential role in epithelial morphogenesis through its cochaperone function of myosin VB and that UNC45A loss causes a variant of microvillus inclusion disease.

Pediatric dysphagia overview: best practice recommendation study by multidisciplinary experts.

BACKGROUND: Currently, there is no comprehensive and multidisciplinary recommendation study covering all aspects of pediatric dysphagia (PD). This study aimed to generate PD management recommendations with methods that can be used in clinical practice to fill this gap in our country and in the world, from the perspective of experienced multidisciplinary experts. METHODS: This recommendation paper was generated by a multidisciplinary team, using the seven-step process and a three-round modified Delphi survey via e-mail. First, ten open-ended questions were created, and then detailed recommendations including management, diagnosis, treatment, and follow-up were created with the answers from these questions. Each recommendation item was voted on by the experts as overall consensus (strong recommendation), approaching consensus (weak recommendation) and divergent consensus (not recommended). RESULTS: In the 1st Delphi round, a questionnaire of 414 items was prepared based on the experts' responses to ten open-ended questions. In the 2nd Delphi round, 59.2% of these items were accepted as pre-recommendation. In the 3rd Delphi round, 62.6% of 246 items were accepted for inclusion in the proposals. The final version recommendations consisted of 154 items. CONCLUSIONS: This study includes comprehensive and detailed answers for every problem that could be posed in clinical practice for the management of PD, and recommendations are for all pediatric patients with both oropharyngeal and esophageal dysphagia.

Cancer and constitutional Mismatch Repair Deficiency syndrome due to homozygous MSH 6 mutation in children with Café au Lait Spots and review of literature.

BACKGROUND: Constitutional mismatch repair deficiency (CMMRD) syndrome is a rare childhood cancer predisposition syndrome resulting from biallelic germline mutations of mismatch repair (MMR) genes. CMMRD syndrome is characterised by early onset malignancies in children. CASE: Here we present affected children of consanguinous parents diagnosed with CMMRD syndrome due to germline bi-allelic MSH 6 gene mutations with café au lait spots and multiple family cancers from Turkey and reported cases with CMMRD syndrome associated MSH 6 mutation in English literature. Hence, we reviewed English literature from 1990 to 2020 using Pub-Med database. Keywords used to search included constitutional mismatch repair deficiency syndrome, childhood cancer and MSH 6 gene mutation. CONCLUSIONS: We emphasize that the inclusion of CMMRD syndrome in the differential diagnosis of a patient who presents with cafe´ au lait spots and/or hypopigmented skin lesions and cancer especially when consanguinity and/or a history of cancer coexist in children.

IgG4-related disease and ANCA positive vasculitis in childhood: a case-based review.

Autoimmune pancreatitis (AIP) type 1 is an IgG4-related disease (IgG4-RD), characterized by inflammatory pseudotumors and histologically by dense lymphoplasmacytic infiltrates rich in IgG4 positive plasma cells, storiform fibrosis, and obliterative phlebitis. Although quite rare, IgG4-RD was found to be associated with medium or small vessel vasculitides. A new overlap syndrome between IgG4-RD and ANCA-associated vasculitis (AAV) has recently been described in the adult population. Here we present a 16-year-old adolescent girl admitted with abdominal pain, episcleritis, palpable purpura, salivary gland enlargement, and bloody diarrhea. Laboratory investigations revealed findings of glomerulonephritis. Abdominal imaging surprisingly revealed a focal mass in the pancreatic tail, while the c-ANCA level was found to be quite high as well as serum IgG4 level. Biopsy of the pancreatic mass showed lymphoplasmacytic IgG4 positive cells infiltrating the pancreas with storiform fibrosis compatible with IgG4-related AIP. The renal biopsy that was done simultaneously showed necrotizing granulomatous vasculitis indicating AAV. Renal biopsy showed IgG4 positive plasma cells very rarely by immunohistochemical examination, which does not indicate any significance for IgG4-RD. Our diagnosis was IgG4-related AIP and AAV overlap syndrome, which has not been reported in the pediatric populations yet. IgG4-RD should be investigated in patients with ANCA-associated vasculitis who shows atypical organ involvement. We searched the Pubmed/Medline and Google Scholar databases to identify clinical findings, treatment, and outcome of the patients with IgG4-related AIP and AAV.

Congenital Diarrhea and Cholestatic Liver Disease: Phenotypic Spectrum Associated with MYO5B Mutations.

Myosin Vb (MYO5B) is a motor protein that facilitates protein trafficking and recycling in polarized cells by RAB11- and RAB8-dependent mechanisms. Biallelic MYO5B mutations are identified in the majority of patients with microvillus inclusion disease (MVID). MVID is an intractable diarrhea of infantile onset with characteristic histopathologic findings that requires life-long parenteral nutrition or intestinal transplantation. A large number of such patients eventually develop cholestatic liver disease. Bi-allelic MYO5B mutations are also identified in a subset of patients with predominant early-onset cholestatic liver disease. We present here the compilation of 114 patients with disease-causing MYO5B genotypes, including 44 novel patients as well as 35 novel MYO5B mutations, and an analysis of MYO5B mutations with regard to functional consequences. Our data support the concept that (1) a complete lack of MYO5B protein or early MYO5B truncation causes predominant intestinal disease (MYO5B-MVID), (2) the expression of full-length mutant MYO5B proteins with residual function causes predominant cholestatic liver disease (MYO5B-PFIC), and (3) the expression of mutant MYO5B proteins without residual function causes both intestinal and hepatic disease (MYO5B-MIXED). Genotype-phenotype data are deposited in the existing open MYO5B database in order to improve disease diagnosis, prognosis, and genetic counseling.

Novel mutations of SAR1B gene in four children with chylomicron retention disease.

BACKGROUND: Intestinal lipid malabsorption, resulting from an impaired formation or secretion of chylomicrons and associated with severe hypobetalipoproteinemia (HBL), may be due to biallelic mutations in APOB (homozygous FHBL type-1), MTTP (abetalipoproteinemia), or SAR1B (chylomicron retention disease). OBJECTIVE: We investigated four children, each born from consanguineous parents, presenting with steatorrhea, malnutrition, accumulation of lipids in enterocytes, and severe hypocholesterolemia with an apparent recessive transmission. METHODS: We sequenced a panel of genes whose variants may be associated with HBL. RESULTS: Case 1, a 9-month-old male, was found to be homozygous for a SAR1B variant (c.49 C>T), predicted to encode a truncated Sar1b protein devoid of function (p.Gln17*). Case 2, a 4-year-old male, was found to be homozygous for a SAR1B missense variant [c.409 G>C, p.(Asp137His)], which affects a highly conserved residue close to the Sar1b guanosine recognition site. Case 3, a 6-year-old male, was found to be homozygous for an ∼6 kb deletion of the SAR1B gene, which eliminates exon 2; this deletion causes the loss of the ATG translation initiation codon in the SAR1B mRNA. The same homozygous mutation was found in an 11-month-old child (case 4) who was related to case 3. CONCLUSIONS: We report 4 children with intestinal lipid malabsorption were found to have chylomicron retention disease due to 3 novel variants in the SAR1B gene.