Broad Phenotype Research Articles

2-Deoxy-4-epi-scyllo-inosose (DEI) is the Product of EboD, a Highly Conserved Dehydroquinate Synthase-like Enzyme in Bacteria and Eustigmatophyte Algae.

A cryptic cluster of genes, known as the ebo cluster, has been found in a variety of genomic contexts among bacteria and algae. In Pseudomonas fluorescens NZI7, the ebo cluster (a.k.a. EDB cluster) is involved in the bacterial repellent mechanism against nematode grazing. In cyanobacteria, the cluster plays a role in the transport of the scytonemin monomer from the cytosol to the periplasm. Despite their broad distribution and interesting phenotypes, neither the pathway nor the functions of the enzymes are known. Here we show that EboD proteins from the ebo clusters in Nostoc punctiforme and Sporocytophaga myxococcoides catalyze the cyclization of mannose 6-phosphate to a novel cyclitol, 2-deoxy-4-epi-scyllo-inosose. The enzyme product is postulated to be a precursor of a signaling molecule or a transporter in the organisms. This study sheds the first light onto ebo/EDB pathways and established a functionally distinct enzyme that extends the diversity of sugar phosphate cyclases.

Unraveling the shared genetics of common epilepsies and general cognitive ability

PurposeCognitive impairment is prevalent among individuals with epilepsy, and increasing evidence indicates that genetic factors can underlie this relationship. However, the extent to which epilepsy subtypes differ in their genetic relationship with cognitive function, and information about the specific genetic variants involved remain largely unknown. MethodsWe investigated the genetic relationship between epilepsies and general cognitive ability (COG) using complementary statistical tools, including linkage disequilibrium score (LDSC) regression, MiXeR and conjunctional false discovery rate (conjFDR). We analyzed genome-wide association study data on COG (n = 269,867) and common epilepsies (n = 27,559 cases, 42,436 controls), including the broad phenotypes ‘all epilepsy’, focal epilepsies and genetic generalized epilepsies (GGE), as well as specific subtypes. We functionally annotated the identified loci using several biological resources and validated the results in independent samples. ResultsUsing MiXeR, COG (11.2k variants) was estimated to be almost four times more polygenic than ‘all epilepsy’, GGE, juvenile myoclonic epilepsy (JME), and childhood absence epilepsy (CAE) (2.5k – 2.9k variants). The other epilepsy phenotypes were insufficiently powered for MiXeR analysis. We quantified extensive genetic overlap between COG and epilepsy types, but with varying negative genetic correlations (-0.23 to -0.04). COG was estimated to share 2.9k variants with both GGE and ‘all epilepsy’, and 2.3k variants with both JME and CAE. Using conjFDR, we identified 66 distinct loci shared between COG and epilepsies, including novel associations for GGE (27), ‘all epilepsy’ (5), JME (5) and CAE (5). The implicated genes were significantly expressed in multiple brain regions. The results were validated in independent samples (COG: p = 3.62 × 10–7; ‘all epilepsy’: p = 2.58 × 10–3). ConclusionOur study further dissects the substantial genetic basis shared between epilepsies and COG and identifies novel shared loci. An improved understanding of the genetic relationship between epilepsies and COG may lead to the development of novel comorbidity-targeted epilepsy treatments.

A clinical phenotype of VEXAS syndrome with pleural effusion, infiltrates, and systemic inflammation in a 76-year-old patient: a case report

IntroductionVEXAS syndrome, characterized by a UBA1 gene mutation, is a rare and severe systemic inflammatory disease predominantly affecting men. Since its initial description in 2020, it has been noted for its broad clinical phenotype and frequent misdiagnosis.Case PresentationA 76-year-old Caucasian male patient diagnosed with VEXAS syndrome is presented in this case report. He presented with typical symptoms including pulmonary manifestations (infiltrates and effusions), systemic inflammation, and haematological abnormalities. The diagnosis was challenging due to the disease's heterogeneous presentation, often resembling autoimmune or haematological diseases. This patient’s case featured ground-glass opacities and pleural effusions, underlining the significant pulmonary involvement seen in 50–67% of VEXAS patients. His condition was further complicated by recurrent fever and systemic inflammation affecting multiple organs.ConclusionVEXAS syndrome demands an aggressive treatment approach due to its high mortality rate and refractory nature. This case underscores the importance of including VEXAS syndrome in differential diagnoses, particularly for patients with systemic inflammation and pulmonary symptoms, and calls for multidisciplinary management and extensive research to understand its full range of clinical phenotypes.

Deficiency of Adenosine Deaminase 2

Adenosine deaminase 2 (ADA2) deficiency is an autosomal recessively inherited autoinflammatory disorder caused by loss-of-function mutations in the ADA2 gene. Although the pathogenesis involves the triggering of a proinflammatory cascade due to increased production of inflammatory cytokines such as tumor necrosis factor (TNF)-α and dysregulation of neutrophil extracellular trap formation resulting from an excess accumulation of extracellular adenosine, the pathogenetic mechanism still needs further clarification due to the broad clinical spectrum. In addition to the initially described vasculitis-related symptoms, hematological, immunological, and autoinflammatory symptoms are now well recognized. The diagnosis is made by demonstration of pathogenic variants of ADA2 with biallelic loss of function and identification of low plasma ADA2 catalytic activity. Currently, TNF-α inhibitors are the treatment of choice for controlling vasculitis manifestations and preventing strokes. However, in patients presenting with severe hematologic findings, TNF-α inhibitors are not the treatment of choice and hematopoietic stem cell transplantation has been shown to be successful in selected cases. Recombinant ADA2 protein and gene therapy are promising treatment modalities for the future. In conclusion, ADA2 deficiency has a broad phenotype and should be considered in the differential diagnosis of different clinical situations. In this review, we summarize the disease manifestations of ADA2 deficiency and available treatment options.

Cardiovascular toxicities of immune therapies for cancer-a scientific statement of the Heart Failure Association (HFA) of the ESC and the ESC Council of Cardio-Oncology.

The advent of immunological therapies has revolutionized the treatment of solid and haematological cancers over the last decade. Licensed therapies which activate the immune system to target cancer cells can be broadly divided into two classes. The first class are antibodies that inhibit immune checkpoint signalling, known as immune checkpoint inhibitors (ICIs). The second class are cell-based immune therapies including chimeric antigen receptor T lymphocyte (CAR-T) cell therapies, natural killer (NK) cell therapies, and tumour infiltrating lymphocyte (TIL) therapies. The clinical efficacy of all these treatments generally outweighs the risks, but there is a high rate of immune-related adverse events (irAEs), which are often unpredictable in timing with clinical sequalae ranging from mild (e.g. rash) to severe or even fatal (e.g. myocarditis, cytokine release syndrome) and reversible to permanent (e.g. endocrinopathies).The mechanisms underpinning irAE pathology vary across different irAE complications and syndromes, reflecting the broad clinical phenotypes observed and the variability of different individual immune responses, and are poorly understood overall. Immune-related cardiovascular toxicities have emerged, and our understanding has evolved from focussing initially on rare but fatal ICI-related myocarditis with cardiogenic shock to more common complications including less severe ICI-related myocarditis, pericarditis, arrhythmias, including conduction system disease and heart block, non-inflammatory heart failure, takotsubo syndrome and coronary artery disease. In this scientific statement on the cardiovascular toxicities of immune therapies for cancer, we summarize the pathophysiology, epidemiology, diagnosis, and management of ICI, CAR-T, NK, and TIL therapies. We also highlight gaps in the literature and where future research should focus.

A correctable immune niche for epithelial stem cell reprogramming and post-viral lung diseases.

Epithelial barriers are programmed for defense and repair but are also the site of long-term structural remodeling and disease. In general, this paradigm features epithelial stem cells (ESCs) that are called on to regenerate damaged tissues but can also be reprogrammed for detrimental remodeling. Here we identified a Wfdc21-dependent monocyte-derived dendritic cell (moDC) population that functioned as an early sentinel niche for basal ESC reprogramming in mouse models of epithelial injury after respiratory viral infection. Niche function depended on moDC delivery of ligand GPNMB to the basal ESC receptor CD44 so that properly timed antibody blockade of ligand or receptor provided long-lasting correction of reprogramming and broad disease phenotypes. These same control points worked directly in mouse and human basal ESC organoids. Together, the findings identify a mechanism to explain and modify what is otherwise a stereotyped but sometimes detrimental response to epithelial injury.

Increased frequency of infections and autoimmune disease in adults with PTEN Hamartoma Tumour Syndrome

There are indications for immune dysregulation in PTEN Hamartoma Tumour Syndrome (PHTS), however information on the clinical immune phenotype is lacking. We aimed to assess the frequency of infections and autoimmune disease in PHTS patients. A retrospective cohort study including 81 paediatric and 109 adult PHTS patients and 73 female adult controls and self-reported data from yearly surveillance visits. Differences between adult patients and controls were assessed with odds ratios (OR). Of paediatric patients, 1% reported fungal infections, 23% tonsillectomy/adenoidectomy, 36% bacterial infections requiring antibiotics, and 2% autoimmune disease. Of adult patients, up to 67% repeatedly reported fungal infections, and 73% was ever affected which was similar to controls. Compared to controls, adult patients more often reported (signs of) viral infections: tonsillectomy/adenoidectomy (78%; OR = 7.4 (95%CI: 3.7–15.8)), frequent infections during childhood (43%; OR = 2.5 (95%CI: 1.3–5.2)), and flu or cold infections more often than others (49%; OR = 3.9 (95%CI: 2.0–8.0)). Autoimmune disease was also more frequent (24%, OR = 2.7 (95%CI: 1.1–7.3)) in adult patients, and antibiotics use (38%, OR = 4.7 (95%CI: 1.3–23.0)) in female adult patients. PHTS patients experience a broad clinical phenotype of immune dysregulation. At adult age, this consists of more often viral and bacterial infections and autoimmune disease, and repetitive fungal infections.

Phylogenomic and genomic analysis reveals unique and shared genetic signatures of Mycobacterium kansasii complex species.

Species belonging to the Mycobacterium kansasii complex (MKC) are frequently isolated from humans and the environment and can cause serious diseases. The most common MKC infections are caused by the species M. kansasii (sensu stricto), leading to tuberculosis-like disease. However, a broad spectrum of virulence, antimicrobial resistance and pathogenicity of these non-tuberculous mycobacteria (NTM) are observed across the MKC. Many genomic aspects of the MKC that relate to these broad phenotypes are not well elucidated. Here, we performed genomic analyses from a collection of 665 MKC strains, isolated from environmental, animal and human sources. We inferred the MKC pangenome, mobilome, resistome, virulome and defence systems and show that the MKC species harbours unique and shared genomic signatures. High frequency of presence of prophages and different types of defence systems were observed. We found that the M. kansasii species splits into four lineages, of which three are lowly represented and mainly in Brazil, while one lineage is dominant and globally spread. Moreover, we show that four sub-lineages of this most distributed M. kansasii lineage emerged during the twentieth century. Further analysis of the M. kansasii genomes revealed almost 300 regions of difference contributing to genomic diversity, as well as fixed mutations that may explain the M. kansasii's increased virulence and drug resistance.

Goal-Directed Use of Prothrombin Complex Concentrates in Liver Transplantation: Is a Plasma-Free Procedure Feasible?

Background: Fresh frozen plasma (FFP) transfusions have been the mainstay of hemostatic intervention for the treatment of bleeding and coagulation abnormalities arising during liver transplantation (LT) for decades. However, numerous clinical studies showed that FFP has many side effects, including the risk of pathogen transmission, transfusion-associated circulatory overload (TACO), transfusion-related immunomodulation (TRIM), and transfusion-related acute lung injury (TRALI). These adverse events are particularly challenging in patients undergoing LT, who often suffer from severe portal hypertension, poor renal function and coexisting cardiac disease.The aims of this review are to summarize the pharmacological properties of currently available PCCs, to represent the theoretical benefits and the possible risks related to the use of these drugs in patients undergoing LT, and, finally, to review the current literature on the topic in order to highlight the evidence that currently supports PCC use in LT patients. Methods: The current literature on the topic was reviewed in order to highlight the evidence that currently supports PCC use in LT patients. Results: Prothrombin complex concentrates (PCCs) may offer several advantages when compared to FFP. Indeed, PCCs have been shown to reduce the risk of TACO, which during liver transplantation may deteriorate portal hypertension, increase intraoperative bleeding, and possibly reduce survival rates. One of the major concerns for PCC use is thrombogenicity. However, currently available PCCs are much safer as they contain inactivated forms of the vitamin K-dependent coagulation factors and protein C, protein S, antithrombin and/or heparin. Nowadays, the use of PCCs to correct coagulation abnormalities that occur during LT is an increasingly widespread practice. However, it is not yet clear what level of evidence supports this practice, and what the risks associated with it are. Conclusions: Administration of PCC in LT patients to correct haemostatic abnormalities seems to be well-tolerated, but the relationship between PCC use and thromboembolic events in the postoperative period remains unclear. Adequately powered, methodologically sound trials are urgently required for more definitive conclusions about the efficacy and safety of PCCs in a broad phenotype of LT recipients.

Characterisation of phenotypic patterns in equine exercise-associated myopathies.

Equine exercise-associated myopathies are prevalent, clinically heterogeneous, generally idiopathic disorders characterised by episodes of myofibre damage that occur in association with exercise. Episodes are intermittent and vary within and between affected horses and across breeds. The aetiopathogenesis is often unclear; there might be multiple causes. Poor phenotypic characterisation hinders genetic and other disease analyses. The aim of this study was to characterise phenotypic patterns across exercise-associated myopathies in horses. Historical cross-sectional study, with subsequent masked case-control validation study. Historical clinical and histological features from muscle samples (n = 109) were used for k-means clustering and validated using principal components analysis and hierarchical clustering. For further validation, a blinded histological study (69 horses) was conducted comparing two phenotypic groups with selected controls and horses with histopathological features characterised by myofibrillar disruption. We identified two distinct broad phenotypes: a non-classic exercise-associated myopathy syndrome (EAMS) subtype was associated with practitioner-described signs of apparent muscle pain (p < 0.001), reluctance to move (10.85, p = 0.001), abnormal gait (p < 0.001), ataxia (p = 0.001) and paresis (p = 0.001); while a non-specific classic RER subtype was not uniquely associated with any particular variables. No histological differences were identified between subtypes in the validation study, and no identifying histopathological features for other equine myopathies identified in either subtype. Lack of an independent validation population; small sample size of smaller identified subtypes; lack of positive control myofibrillar myopathy cases; case descriptions derived from multiple independent and unblinded practitioners. This is the first study using computational clustering methods to identify phenotypic patterns in equine exercise-associated myopathies, and suggests that differences in patterns of presenting clinical signs support multiple disease subtypes, with EAMS a novel subtype not previously described. Routine muscle histopathology was not helpful in sub-categorising the phenotypes in our population.

Clinical and Genetic Characterization of a Cohort of Brazilian Patients With Congenital Ataxia.

Congenital ataxias are rare hereditary disorders characterized by hypotonia and developmental motor delay in the first few months of life, followed by cerebellar ataxia in early childhood. The course of the disease is predominantly nonprogressive, and many patients are incorrectly diagnosed with cerebral palsy. Despite significant advancements in next-generation sequencing in the past few decades, a specific genetic diagnosis is seldom obtained in cases of congenital ataxia. The aim of the study was to analyze the clinical, radiologic, and genetic features of a cohort of Brazilian patients with congenital ataxia. Thirty patients with a clinical diagnosis of congenital ataxia were enrolled in this study. Clinical and demographic features and neuroimaging studies were analyzed. Genetic testing (whole-exome sequencing) was also performed. A heterogeneous pattern of genetic variants was detected. Eighteen genes were involved: ALDH5A1, BRF1, CACNA1A CACNA1G, CC2D2A, CWF19L1, EXOSC3, ITPR1, KIF1A, MME, PEX10, SCN2A, SNX14, SPTBN2, STXBP1, TMEM240, THG1L, and TUBB4A. Pathogenic/likely pathogenic variants involving 11 genes (ALDH5A1, CACNA1A, EXOSC3, MME, ITPR1, KIF1A, STXBP1, SNX14, SPTBN2, TMEM240, and TUBB4A) were identified in 46.7% of patients. Variants of uncertain significance involving 8 genes were detected in 33.3% of patients. Congenital ataxias were characterized by a broad phenotype. A genetic diagnosis was more often obtained in patients with cerebellar-plus syndrome than in patients with a pure cerebellar syndrome. This study re-emphasizes the genetic heterogeneity of congenital ataxias and the absence of a clear phenotype-genotype relationship. A specific genetic diagnosis was established in 46.7% of patients. Autosomal dominant, associated with sporadic cases, was recognized as an important genetic inheritance. The results of this analysis highlight the value of whole-exome sequencing as an efficient screening tool in patients with congenital ataxia.

Expanding the phenotypic and genotypic spectrum of DYT-TUBB4A with seven patients from India

BackgroundVariants in the TUBB4A gene are associated with dystonia (DYT-TUBB4A), Hypomyelination with Atrophy of the Basal Ganglia and Cerebellum (H-ABC) and spastic paraplegia. Phenotypes intermediate to these three broad phenotypes are also observed. These are rare disorders, and data from diverse populations remains limited. We report seven Indian cases with dystonia phenotype related to TUBB4A mutation. CasesAmong these seven patients, age at onset ranged from 5 to 48 years. Five patients had cranio-cervical onset of dystonia. One patient had prominent parkinsonism with dystonia. Patients responded well to botulinum toxin injected for laryngeal, cervical and jaw dystonia. The patient with parkinsonism responded well to levodopa, albeit with development of dyskinesias. Apart from the common p.Arg2Gly variant in three patients with DYT-TUBB4A, other variants included p.Arg262Pro, p.Arg39Cys and p.Asp245Asn. ConclusionsWe report the first collection of cases with TUBB4A mutation from India. We expand the phenotype to include levodopa-responsive parkinsonism. Indian patients, consistent with global literature, harbor prominent adductor dysphonia, cervical and jaw dystonia, which responds well to botulinum treatment.

Characterization of 35 novel NR5A1/SF-1 variants identified in individuals with atypical sexual development: The SF1next study.

Steroidogenic factor 1 (NR5A1/SF-1) is a nuclear receptor that regulates sex development, steroidogenesis and reproduction. Genetic variants in NR5A1/SF-1 are common among differences of sex development (DSD) and associate with a wide range of phenotypes, but their pathogenic mechanisms remain unclear. Novel, likely disease-causing NR5A1/SF-1 variants from the SF1next cohort of individuals with DSD were characterized to elucidate their pathogenic effect. Different in silico tools were used to predict the impact of novel NR5A1/SF-1 variants on protein function. An extensive literature review was conducted to compare and select the best functional studies for testing the pathogenic effect of the variants in a classic cell culture model. The missense NR5A1/SF-1 variants were tested on the promoter luciferase reporter vector -152CYP11A1_pGL3 in HEK293T cells and assessed for their cytoplasmic/nuclear localization by Western blot. Thirty-five novel NR5A1/SF-1 variants were identified in the SF1next cohort. Seventeen missense NR5A1/SF-1 variants were functionally tested. Transactivation assays showed reduced activity for 40% of the variants located in the DNA binding domain and variable activity for variants located elsewhere. Translocation assessment revealed three variants (3/17) with affected nuclear translocation. No clear genotype-phenotype, structure-function correlation was found. Genetic analyses and functional assays do not explain the observed wide phenotype of individuals with these novel NR5A1/SF-1 variants. In nine individuals, additional likely disease-causing variants in other genes were found, strengthening the hypothesis that the broad phenotype of DSD associated with NR5A1/SF-1 variants may be caused by an oligogenic mechanism.

Variants in Candidate Genes for Phenotype Heterogeneity in Patients with the 22q11.2 Deletion Syndrome.

22q11.2 deletion syndrome (22q11.2DS) is a microdeletion syndrome with a broad and heterogeneous phenotype, even though most of the deletions present similar sizes, involving ∼3 Mb of DNA. In a relatively large population of a Brazilian 22q11.2DS cohort (60 patients), we investigated genetic variants that could act as genetic modifiers and contribute to the phenotypic heterogeneity, using a targeted NGS (Next Generation Sequencing) with a specific Ion AmpliSeq panel to sequence nine candidate genes (CRKL, MAPK1, HIRA, TANGO2, PI4KA, HDAC1, ZDHHC8, ZFPM2, and JAM3), mapped in and outside the 22q11.2 hemizygous deleted region. In silico prediction was performed, and the whole-genome sequencing annotation analysis package (WGSA) was used to predict the possible pathogenic effect of single nucleotide variants (SNVs). For the in silico prediction of the indels, we used the genomic variants filtered by a deep learning model in NGS (GARFIELD-NGS). We identified six variants, 4 SNVs and 2 indels, in MAPK1, JAM3, and ZFPM2 genes with possibly synergistic deleterious effects in the context of the 22q11.2 deletion. Our results provide the opportunity for the discovery of the co-occurrence of genetic variants with 22q11.2 deletions, which may influence the patients´ phenotype.

Monocytes and Macrophages in Kidney Disease and Homeostasis.

The monocyte-macrophage lineage of inflammatory cells is characterized by significant morphologic and functional plasticity. Macrophages have broad M1 and M2 phenotype subgroups with distinctive functions and dual reno-toxic and reno-protective effects. Macrophages are a major contributor to injury in immune-complex-mediated, as well as pauci-immune, glomerulonephritis. Macrophages are also implicated in tubulointerstitial and vascular disease, though there have not been many human studies. Patrolling monocytes in the intravascular compartment have been reported in auto-immune injury in the renal parenchyma, manifesting as acute kidney injury. Insights into the pathogenetic roles of macrophages in renal disease suggest potentially novel therapeutic and prognostic biomarkers and targeted therapy. This review provides a concise overview of the macrophage-induced pathogenetic mechanism as a background for the latest findings about macrophages' roles in different renal compartments and common renal diseases.

The Potential Mechanisms Behind Adverse Effect of Coronavirus Disease-19 on Heart and Liver Damage: A Review.

Coronaviruses (CoVs) belong to the RNA viruses family. The viruses in this family are known to cause mild respiratory disease in humans. The origin of the novel SARS-COV2 virus that caused the coronavirus-19 disease (COVID-19) is the Wuhan city in China from where it disseminated to cause a global pandemic. Although lungs are the predominant target organ for Coronavirus Disease-19 (COVID-19), since its outbreak, the disease is known to affect heart, blood vessels, kidney, intestine, liver and brain. This review aimed to summarize the catastrophic impacts of Coronavirus disease-19 on heart and liver along with its mechanisms of pathogenesis. The information used in this review was obtained from relevant articles published on PubMed, Google Scholar, Google, WHO website, CDC and other sources. Key searching statements and phrases related to COVID-19 were used to retrieve information. Original research articles, review papers, research letters and case reports were used as a source of information. Besides causing severe lung injury, COVID-19 has also been reported to affect and cause dysfunction of many other organs. COVID-19 infection can affect people by downregulating membrane-bound active angiotensin-converting enzyme (ACE). People who have deficient ACE2 expression are more vulnerable to COVID-19 infection. The patients' pre-existing co-morbidities are major risk factors that predispose individuals to severe COVID-19. The disease severity and its broad spectrum phenotype is a result of combined direct and indirect pathogenic factors. Therefore, protocols that harmonize many therapeutic preferences should be the best alternatives to de-escalate the disease and obviate deaths caused as a result of multiple organ damage and dysfunction induced by the disease.

A286 MYO5B MUTATIONS AS A CAUSE OF CHOLESTASIS IN A CHILD WITHOUT MICROVILLOUS INCLUSION DISEASE

Abstract Background Biallelic Myosin Vb (MYO5B) mutations are identified in the majority of patients with microvillus inclusion disease (MVID) that requires life-long parenteral nutrition and eventually cholestatic liver disease. Biallelic MYO5B mutations have also been reported in a few children with predominant early-onset cholestatic liver disease. Aims To report on a patient with MYO5B mutations and progressive familial intrahepatic cholestasis PFIC-like phenotype and normal serum GGT without intestinal disease. Methods We describe a 2-year and 8-month-old girl, who is the first child of healthy non- consanguineous parents from the Phillipines with no family history of liver disease. She presented at the age of 10 months for evaluation of mild jaundice, which was noticed at the age of 6 months. Other symptoms included pruritus, slowly weight gain, intermittent pale stools and dark urine. Laboratory investigations revealed AST 99, ALT 87, GGT 27, conjugated bilirubin 13 and INR 0.8. Fasting abdominal ultrasound was normal apart from a possibly hypoplastic gallbladder and mild splenomegaly. Additional investigations revealed normal thyroid-stimulating hormone, cortisol, galactosemia screening and sweat chloride, but bile acids were elevated 391.6 umol/L. A liver biopsy was performed and a cholestasis genetic panel sent. The patient was started on ursodiol, hydroxyzine, rifampicin and vitamin D. Results Liver biopsy revealed moderate hepato-canalicular cholestasis, bile duct injury without prominent ductopenia, small caliber bile ducts with no features of obstructive cholangiopathy, mild periportal and pericentral fibrosis stage 1-2/ 4. Electron microscopy demonstrated cytoplasmic and canalicular bile accumulation. The bile canaliculi were variably distended by coarse granular bile. Immunohistochemical staining for BSEP and MDR3, showed canalicular staining in zones 1 and absence of staining in zones 2 and 3. Genetic analysis revealed one pathogenic variant and one variant of uncertain significance in MYO5B. No mutations in ABCB11 or ATP8B1 genes were identified. On follow-up, the jaundice improved, pruritus was managed with the medications described above. Her growth has improved and she is growing on the 25th centiles. She has not developed any gastrointestinal symptoms. Conclusions We present a patient with MYO5B mutations who presented with normal GGT cholestasis and a liver biopsy consistent with PFIC, without any evidence of intestinal disease. Because MYO5B mutations disrupt the intracellular trafficking of brush border proteins in the intestine, it has been assumed that it similarly disrupts the trafficking of the canalicular bile acid transporting and bilirubin transporting proteins in the liver. This case highlights the broad phenotype associated with MYO5B variants. Funding Agencies None

Diagnostic journey for individuals with fibrous dysplasia / McCune albright syndrome (FD/MAS)

BackgroundReducing delayed diagnosis is a significant healthcare priority for individuals with rare diseases. Fibrous Dysplasia/ McCune Albright Syndrome (FD/MAS) is a rare bone disease caused by somatic activation mutations of NASA. FD/MAS has a broad clinical phenotype reflecting variable involvement of bone, endocrine and other tissues, distribution and severity. The variable phenotype is likely to prolong the diagnostic journey for patients further.AimTo describe the time from symptom onset to final diagnosis in individuals living with FDMAS.MethodsWe used the UK-based RUDY research database (www.rudystudy.org), where patients self-report their diagnosis of FD/MAS. Participants are invited to complete the diagnostic journey based on the EPIRARE criteria.Results51 individuals diagnosed with FD/MAS were included in this analysis. Among them, 70% were female, and the median age was 51.0 years (IQR 34.5–57.5]. 12 (35%) individuals reported McCune Albright Syndrome, 11 (21.6%) craniofacial and 11(21.6%) for each of poly- and mono-ostotic FD and 6 (11.8%) did not know their type of FD/MAS. Pain was the commonest first symptom (58.8%), and 47.1% received another diagnosis before the diagnosis of FD/MAS. The median time to final diagnosis from the first symptom was two years with a wide IQR (1,18) and range (0–59 years). Only 12 (23.5%) of individuals were diagnosed within 12 months of their first symptoms. The type of FD/MAS was not associated with the reported time to diagnosis. Significant independent predictors of longer time to final diagnosis included older current age, younger age at first symptom and diagnosis after 2010.ConclusionIndividuals with FDMAS have a variable time to diagnosis that can span decades. This study highlights the need for further research on how to improve diagnostic pathways within Orthopaedic and Ear, Nose and Throat (ENT)/Maxillofacial services. Our data provides a baseline to assess the impact of novel NHS diagnostic networks on reducing the diagnostic odyssey.

Immune-Related Adverse Events of Immune Checkpoint Inhibitors.

Immune-related adverse events (irAEs) are toxicities that arise after the administration of monoclonal antibodies targeting immune checkpoints (immune checkpoint inhibitors [ICIs]) in patients with cancer. They can occur at any time after initiation of ICI treatment, with a broad clinical phenotype that can be organ-specific or systemic. Although most irAEs manifest as mild to moderate signs and symptoms, severe forms of irAEs can lead to irreversible organ failure and have acute life-threatening presentations. Treatment should be tailored to the specific organ involved and the severity. Glucocorticoids are the first-line treatment for most irAEs, with immunosuppressants and biologics mainly used as second-line treatments.

Comparing broad and narrow phenotype algorithms: differences in performance characteristics and immortal time incurred.

Introduction: When developing phenotype algorithms for observational research, there is usually a trade-off between definitions that are sensitive or specific. The objective of this study was to estimate the performance characteristics of phenotype algorithms designed for increasing specificity and to estimate the immortal time associated with each algorithm. Materials and methods: We examined algorithms for 11 chronic health conditions. The analyses were from data from five databases. For each health condition, we created five algorithms to examine performance (sensitivity and positive predictive value (PPV)) differences: one broad algorithm using a single code for the health condition and four narrow algorithms where a second diagnosis code was required 1-30days, 1-90days, 1-365days, or 1- all days in a subject's continuous observation period after the first code. We also examined the proportion of immortal time relative to time-at-risk (TAR) for four outcomes. The TAR's were: 0-30days after the first condition occurrence (the index date), 0-90days post-index, 0-365days post-index, and 0-1,095days post-index. Performance of algorithms for chronic health conditions was estimated using PheValuator (V2.1.4) from the OHDSI toolstack. Immortal time was calculated as the time from the index date until the first of the following: 1) the outcome; 2) the end of the outcome TAR; 3) the occurrence of the second code for the chronic health condition. Results: In the first analysis, the narrow phenotype algorithms, i.e., those requiring a second condition code, produced higher estimates for PPV and lower estimates for sensitivity compared to the single code algorithm. In all conditions, increasing the time to the required second code increased the sensitivity of the algorithm. In the second analysis, the amount of immortal time increased as the window used to identify the second diagnosis code increased. The proportion of TAR that was immortal was highest in the 30days TAR analyses compared to the 1,095days TAR analyses. Conclusion: Attempting to increase the specificity of a health condition algorithm by adding a second code is a potentially valid approach to increase specificity, albeit at the cost of incurring immortal time.