Rare Disease Research Articles

Therapeutic potential of oleic acid supplementation in myotonic dystrophy muscle cell models

BackgroundWe recently reported that upregulation of Musashi 2 (MSI2) protein in the rare neuromuscular disease myotonic dystrophy type 1 contributes to the hyperactivation of the muscle catabolic processes autophagy and UPS through a reduction in miR-7 levels. Because oleic acid (OA) is a known allosteric regulator of MSI2 activity in the biogenesis of miR-7, here we sought to evaluate endogenous levels of this fatty acid and its therapeutic potential in rescuing cell differentiation phenotypes in vitro. In this work, four muscle cell lines derived from DM1 patients were treated with OA for 24 h, and autophagy and muscle differentiation parameters were analyzed.ResultsWe demonstrate a reduction of OA levels in different cell models of the disease. OA supplementation rescued disease-related phenotypes such as fusion index, myotube diameter, and repressed autophagy. This involved inhibiting MSI2 regulation of direct molecular target miR-7 since OA isoschizomer, elaidic acid (EA) could not cause the same rescues. Reduction of OA levels seems to stem from impaired biogenesis since levels of the enzyme stearoyl-CoA desaturase 1 (SCD1), responsible for converting stearic acid to oleic acid, are decreased in DM1 and correlate with OA amounts.ConclusionsFor the first time in DM1, we describe a fatty acid metabolism impairment that originated, at least in part, from a decrease in SCD1. Because OA allosterically inhibits MSI2 binding to molecular targets, reduced OA levels synergize with the overexpression of MSI2 and contribute to the MSI2 > miR-7 > autophagy axis that we proposed to explain the muscle atrophy phenotype.

Targeting autophagy impairment improves the phenotype of a novel CLN8 zebrafish model

CLN8 is an endoplasmic reticulum cargo receptor and a regulator of lysosome biogenesis whose loss of function leads to neuronal ceroid lipofuscinosis. CLN8 has been linked to autophagy and lipid metabolism, but much remains to be learned, and there are no therapies acting on the molecular signatures in this disorder. The present study aims to characterize the molecular pathways involved in CLN8 disease and, by pinpointing altered ones, to identify potential therapies. To bridge the gap between cell and mammalian models, we generated a new zebrafish model of CLN8 deficiency, which recapitulates the pathological features of the disease. We observed, for the first time, that CLN8 dysfunction impairs autophagy. Using autophagy modulators, we showed that trehalose and SG2 are able to attenuate the pathological phenotype in mutant larvae, confirming autophagy impairment as a secondary event in disease progression. Overall, our successful modeling of CLN8 defects in zebrafish highlights this novel in vivo model's strong potential as an instrument for exploring the role of CLN8 dysfunction in cellular pathways, with a view to identifying small molecules to treat this rare disease.

A Comprehensive Review of the Impact of Machine Learning and Omics on Rare Neurological Diseases

Background: Rare diseases, predominantly caused by genetic factors and often presenting neurological manifestations, are significantly underrepresented in research. This review addresses the urgent need for advanced research in rare neurological diseases (RNDs), which suffer from a data scarcity and diagnostic challenges. Bridging the gap in RND research is the integration of machine learning (ML) and omics technologies, offering potential insights into the genetic and molecular complexities of these conditions. Methods: We employed a structured search strategy, using a combination of machine learning and omics-related keywords, alongside the names and synonyms of 1840 RNDs as identified by Orphanet. Our inclusion criteria were limited to English language articles that utilized specific ML algorithms in the analysis of omics data related to RNDs. We excluded reviews and animal studies, focusing solely on studies with the clear application of ML in omics data to ensure the relevance and specificity of our research corpus. Results: The structured search revealed the growing use of machine learning algorithms for the discovery of biomarkers and diagnosis of rare neurological diseases (RNDs), with a primary focus on genomics and radiomics because genetic factors and imaging techniques play a crucial role in determining the severity of these diseases. With AI, we can improve diagnosis and mutation detection and develop personalized treatment plans. There are, however, several challenges, including small sample sizes, data heterogeneity, model interpretability, and the need for external validation studies. Conclusions: The sparse knowledge of valid biomarkers, disease pathogenesis, and treatments for rare diseases presents a significant challenge for RND research. The integration of omics and machine learning technologies, coupled with collaboration among stakeholders, is essential to develop personalized treatment plans and improve patient outcomes in this critical medical domain.

Time to diagnosis and determinants of diagnostic delays of people living with a rare disease: results of a Rare Barometer retrospective patient survey.

Timely diagnosis is one of the most serious challenges faced by people living with a rare disease (PLWRD), and this study estimates that in Europe, the average total diagnosis time (TDT) is close to 5 years. We investigated the duration of the TDT for PLWRD in Europe, the difficulties associated with their diagnosis odyssey and the main determinants of diagnosis delays for all rare diseases (RD). We conducted a survey of PLWRD and their families using Rare Barometer, the survey initiative of EURORDIS-Rare Diseases Europe. In geographical Europe, we surveyed 6507 people living with 1675 RD in 41 countries. We then performed a descriptive analysis and ordinal logistic regressions to identify the main determinants of diagnosis delays. Average TDT is 4.7 years. 56% of respondents were diagnosed more than 6 months after a first medical contact. The main determinants of diagnosis delays are symptom onset before 30 years of age, especially during childhood (OR = 3.11; 95% CI: 2.4-4.0) and adolescence (OR = 4.79; 95% CI: 3.7-6.2), being a woman (OR = 1.22; 95% CI:1.1-1.4), living in Northern Europe (OR = 2.15; 95% CI:1.8-2.6) or Western Europe (OR = 1.96; 95% CI:1.6-2.3), the number of healthcare professionals consulted (OR = 5.15; 95% CI:4.1-6.4), misdiagnosis (OR = 2.48; 95% CI:2.1-2.9), referral to a centre of expertise (OR = 1.17; 95% CI:1.0-1.3), unmet needs for psychological support (OR = 1.34; 95% CI:1.2-1.5) and financial support (OR = 1.16; 95% CI:1.0-1.3), having a genetic disease (OR = 1.33; 95% CI:1.1-1.5) and a family history of an RD (OR = 1.36; 95% CI:1.1-1.6). These determinants can inform policies and actions to improve access to diagnosis for all PLWRD.

LEMD2-associated progeroid syndrome: Expanding the phenotype of the nuclear envelopathy caused by a defect in LEMD2 gene.

Nuclear envelopathies are rare genetic diseases that compromise the integrity of the nuclear envelope. Patients with a defect in LEM domain nuclear envelope protein 2 (LEMD2) leading to LEMD2-associated progeroid syndrome are exceedingly scarce in number, yet they exhibit shared clinical features including skeletal abnormalities and a prematurely-aged appearance. Our study broadens the understanding of LEMD2-associated progeroid syndrome by detailing its phenotypic and molecular characteristics in the first female and fourth reported case, highlighting a distinct impact on metabolic functions. The patient's history revealed growth delay, facial and skeletal abnormalities, and recurrent abdominal pain crises caused by hepatomegaly. Comparisons with the previously documented cases emphasized similarities in skeletal and facial features while showcasing unique variations, notably in cardiac and hepatic manifestations. Invitro experiments conducted on patient-derived peripheral blood and urinary epithelial cells and LEMD2-downregulated HepG2 cells confirmed abnormalities in the structure of the nuclear envelope in all three tissue-types. Overall, our work offers a comprehensive profile of a patient with LEMD2-related syndrome, emphasizing the hepatic involvement in the disease and broadening our understanding of clinical and molecular implications. This study not only contributes specific insights into LEMD2-related conditions but also underscores potential therapeutic paths for disorders affecting nuclear envelope dynamics.

LYME AND DENGUE FEVER: FROM BANGLADESH TO ITALY

Abstract Background Dengue fever (Flavivirus) and Lyme disease (Borrelia burgdorferi) are rare tropical infectious diseases transmitted by hematophagous vectors (Aedes mosquitoes and ticks, respectively), and they are extremely uncommon in Italy. In European countries, both represent a public health concern as they manifest as imported diseases. Case Report A 54–year–old man from Bangladesh was admitted with symptoms of fever, dyspnea, and pericarditic chest pain. Laboratory and imaging examinations revealed severe acute respiratory failure secondary to left lower lobe pneumonia and pleuropericardial effusion. Broad–spectrum antibiotic therapy and anti–inflammatory treatment were initiated, suspecting para–pneumonic pleuropericarditis. During hospitalization, there was a gradual improvement with a reduction in inflammatory indices and resolution of lung consolidation. The patient was discharged after 14 days with anti–inflammatory therapy (ibuprofen and colchicine). Approximately 7 days later, the patient returned to the emergency department complaining of a recurrence of symptoms and fatigue. The EKG showed phases of 2:1 AV block, EAS and EPS, complete de novo left bundle branch block (LBBB), alternating with an escape atrial rhythm, not evident in previous EKG. During hospitalization, complete AV block emerged with prolonged asystolic phases, requiring urgent placement of a temporary pacemaker. Concurrently, blood tests revealed anemia and increased levels of inflammatory markers, troponin, creatinine, transaminases, cholestatic indices, LDH, and lipase, indicative of multiple organ failure (MOF). Acute pathologies or active bleeding were ruled out by total body CT with contrast. Blood cultures and serological tests were performed to exclude infections by Trichinella, Mycoplasma, Borrelia, Dengue, and other rare infectious diseases. Due to progressive deterioration, the patient was transferred to a tertiary care hospital. In the following days, laboratory results showed positive IgG and IgM for Dengue (without serological evidence of viral RNA) and positive IgG and IgM antibodies for Borrelia burgdorferi. Conclusion In Italy, the incidence of these diseases is low, and their coexistence in the same host is even rarer (if not anecdotal). However, coinfection cannot be excluded in patients from areas where these diseases are endemic, such as Bangladesh.

MULTIFOCAL ATRIAL TACHYCARDIA AND HYPERTROPHIC CARDIOMYOPATHY IN THREE PATIENTS WITH COSTELLO SYNDROME

Abstract Introduction Costello syndrome is a rare disease, caused by mutation of the HRAS gene, associated with intellectual disability, growth retardation, facial dimorphisms. Cardiac abnormalities, mainly cardiac hypertrophy and multifocal atrial tachycardia, are present in 1/3 of patients. Clinical Cases From 2019 to 2023, 3 newborns with Costello syndrome came under our observation. M.M. showed respiratory distress, hypotonia and dysmorphic notes; genetic analysis highlighted the pathogenic variant c.64C>A (p.Gln22Lys). On the echocardiogram, septal hypertrophic cardiomyopathy was found with left outflow obstruction and mitral insufficiency. Therapy with propranolol was undertaken. Holter ECG never revealed arrhythmias. At the last check–up, SIV hypertrophy, continent mitral valve, free left ventricular outflow. The second patient, O.L., arrived at 10 days of age following a run of supraventricular tachycardia. He had bilateral clubfoot and facial dimorphisms. The echocardiogram was normal. On Holter ECG atrial tachycardia interrupted by rare sinus beats. Therapy with flecainide was undertaken, without benefit. Subsequently, was undertaken amiodarone, then associated with digitalis. She was discharged with satisfactory control of the average ventricular rate, but later due to the appearance of chaotic atrial arrhythmia, propranolol was added; on the Holter ECG in triple therapy, periods of sinus rhythm alternating with short episodes of atrial tachycardia were observed. Genetic analysis revealed the pathogenic variant c.34G>A, p.(Gly12Ser) of the HRAS gene. The third patient, F.A., presented atrial tachycardia. Flecainide therapy had transient benefit. Subsequently propranolol was added, without benefit. Therapy with amiodarone was initiated. Transesophageal electrophysiological study demonstrated multifocal atrial tachycardia, unresponsive to overdrive pacing. Partial control of the average ventricular rate was achieved in triple therapy. On the echocardiogram, mild concentric hypertrophy and dysplastic pulmonary valve. Genetic testing detected the c.35G>C, p(Gly12Ala) variant of the HRAS gene. Conclusions Costello syndrome requires cardiac monitoring for the possible presence of multifocal atrial tachycardia and hypertrophic cardiomyopathy. Arrhythmia, which can also occur independently of hypertrophy, can be self–limited in the first months of life with aggressive pharmacological treatment but can persist or worsen in ¼ of patients.

Has Coca-Cola treatment become the first-line therapy for gastric bezoars, both in general and specifically for western countries?

Phytobezoars is a rare disease and less common in Western countries. The stomach is the primary site for these formations, and endoscopic treatment involving fragmentation and extraction has traditionally been the most effective approach. However, medical treatments using enzymatic and chemical agents, such as cellulase and Coca-Cola, aimed at dissolving the bezoars, have also been utilized, showing varying degrees of resolution success. Notably, the oral dissolution treatment with Coca-Cola has emerged as a promising, simpler, and more cost-effective method. The study by Liu et al represents an important step in clinical research on this topic, despite some limitations that need addressing for a more comprehensive understanding of its findings. Key considerations for future research include sample size calculation, endoscopic procedure details, outpatient vs. inpatient treatment, and detailed cost calculations. The study's exclusions, such as patients with upper gastric surgery, phytobezoars older than 14 d, and cases of gastroparesis, limit its applicability to broader populations, especially in Western countries. Given the promising outcomes of the Coca-Cola treatment, it's advocated as a first-line therapy for phytobezoars. Nonetheless, further research is essential to overcome these limitations. However special situations such as perforation or small bowel obstruction will require surgical treatment.

ALL THE ROADS LEAD TO THE MYSTERIOUS DISEASE

Abstract A 58–year–old man with familiarity for sudden cardiac death was accepted to the hospital for dyspnea. Two years before he underwent cardiac angiography which showed a significative lesion of the descending artery which was treated with the placement of a drug eluting stent. For the appearance of an atrio–ventricular block 2:1, a permanent pacemaker was implanted. A transthoracic echocardiogram demonstrated: mildly dilated left ventricle with a reduced global systolic function (calculated ejection fraction was of 25%). Computed tomography with intravenous contrast of the chest showed upper, mid and lower multifocal nodularity with irregular margins with predominantly peri –bronchial distribution. The patient underwent bronchoscopy with endotracheal ultrasound and multiple transbronchial biopsies. Bronchoalveolar lavage (BAL) was negative for fungi infections, bacteria (including Mycobacterium Complex), and malignant cells. Endobronchial biopsies revealed non–necrotizing, well–formed granulomas embedded in dense hyaline sclerosis. Also the ratio of CD4+/CD8+ cells was within limits. FDG PET–TC scan showed: multiple enhancing areas in the lungs and lymph nodes probably of an inflammatory nature and therefore compatible with pulmonary sarcoidosis. A high dosage cortisone therapy was started, the patient was transferred to undergo endomyocardial biopsy, subsequently tested positive for multisystemic disease. Sarcoidosis is a rare disease with extremely heterogeneous clinical presentations. Actually, it is characterized by non–necrotizing granulomas, aggregates of epithelial cells, macrophages, multinucleated giant cells and CD4+ T lymphocytes, which infiltrate different tissues. When symptomatic, cardiac sarcoidosis includes conduction abnormalities, arrhythmias and ventricle dilation with hearth failure. Rhythm disorders, which rang from first to third degree, are the most common manifestation together with atrial fibrillation and ventricular tachyarrhythmias which can be explained with reentrant mechanisms from the granulomatous scar. Both atria–ventricular blocks and history of ventricular tachycardia elevate the risk for sudden cardiac death, which may be the first and unique manifestation of the disease. If myocardial involvement is extensive, cardiac sarcoidosis can present with hearth failure.

Assessing the Application of Large Language Models in Generating Dermatologic Patient Education Materials According to Reading Level: Qualitative Study.

Dermatologic patient education materials (PEMs) are often written above the national average seventh- to eighth-grade reading level. ChatGPT-3.5, GPT-4, DermGPT, and DocsGPT are large language models (LLMs) that are responsive to user prompts. Our project assesses their use in generating dermatologic PEMs at specified reading levels. This study aims to assess the ability of select LLMs to generate PEMs for common and rare dermatologic conditions at unspecified and specified reading levels. Further, the study aims to assess the preservation of meaning across such LLM-generated PEMs, as assessed by dermatology resident trainees. The Flesch-Kincaid reading level (FKRL) of current American Academy of Dermatology PEMs was evaluated for 4 common (atopic dermatitis, acne vulgaris, psoriasis, and herpes zoster) and 4 rare (epidermolysis bullosa, bullous pemphigoid, lamellar ichthyosis, and lichen planus) dermatologic conditions. We prompted ChatGPT-3.5, GPT-4, DermGPT, and DocsGPT to "Create a patient education handout about [condition] at a [FKRL]" to iteratively generate 10 PEMs per condition at unspecified fifth- and seventh-grade FKRLs, evaluated with Microsoft Word readability statistics. The preservation of meaning across LLMs was assessed by 2 dermatology resident trainees. The current American Academy of Dermatology PEMs had an average (SD) FKRL of 9.35 (1.26) and 9.50 (2.3) for common and rare diseases, respectively. For common diseases, the FKRLs of LLM-produced PEMs ranged between 9.8 and 11.21 (unspecified prompt), between 4.22 and 7.43 (fifth-grade prompt), and between 5.98 and 7.28 (seventh-grade prompt). For rare diseases, the FKRLs of LLM-produced PEMs ranged between 9.85 and 11.45 (unspecified prompt), between 4.22 and 7.43 (fifth-grade prompt), and between 5.98 and 7.28 (seventh-grade prompt). At the fifth-grade reading level, GPT-4 was better at producing PEMs for both common and rare conditions than ChatGPT-3.5 (P=.001 and P=.01, respectively), DermGPT (P<.001 and P=.03, respectively), and DocsGPT (P<.001 and P=.02, respectively). At the seventh-grade reading level, no significant difference was found between ChatGPT-3.5, GPT-4, DocsGPT, or DermGPT in producing PEMs for common conditions (all P>.05); however, for rare conditions, ChatGPT-3.5 and DocsGPT outperformed GPT-4 (P=.003 and P<.001, respectively). The preservation of meaning analysis revealed that for common conditions, DermGPT ranked the highest for overall ease of reading, patient understandability, and accuracy (14.75/15, 98%); for rare conditions, handouts generated by GPT-4 ranked the highest (14.5/15, 97%). GPT-4 appeared to outperform ChatGPT-3.5, DocsGPT, and DermGPT at the fifth-grade FKRL for both common and rare conditions, although both ChatGPT-3.5 and DocsGPT performed better than GPT-4 at the seventh-grade FKRL for rare conditions. LLM-produced PEMs may reliably meet seventh-grade FKRLs for select common and rare dermatologic conditions and are easy to read, understandable for patients, and mostly accurate. LLMs may play a role in enhancing health literacy and disseminating accessible, understandable PEMs in dermatology.

PARTIALLY REVERSIBLE DILATED CARDIOMYOPATHY ASSOCIATED WITH AMPHOTERICIN B THERAPY

Abstract Background Amphotericin B (AmB) is an antifungal drug commonly used in a broad spectrum of infections, including leishmaniasis. Leishmaniasis, transmitted through insect bites, has cutaneous, mucocutaneous, or visceral (particularly liver and spleen) involvement. The main adverse effects of AmB are cardiotoxicity and nephrotoxicity, often reversible, but with yet unclear pathophysiology. Reversible dilated cardiomyopathy is a rare disease with very few cases described in the literature (less than 10). The Case A 41–year–old man with a silent cardiological history (only cocaine and alcohol abuse in past) is admitted for visceral leishmaniasis. Cardiological evaluation: LBBB in ECG (none previous available); no abnormality detected on ECOCG (EF 55%). Ten days after the AmB cycle, onset of worsening dyspnoea needing hospital treatment after a further two weeks for heart failure (HF). At ECOCG severe left ventricular dysfunction (EF 30%), no rise of cardiac enzymes was detected. Coronary angiography showed 50–75% stenosis on RCA and LAD, treated by angioplasty and stenting. Cardiac MRI showed: dilated left ventricle with diffuse biventricular hypokinesis (FE 16% left and 22% right), areas of LGE of non–ischemic appearance. HFrEF GDMTs were prescribed, with progressive clinical improvement over the next four weeks; at cardiac MRI performed one month later, partially recovery of biventricular function (FE sn 41% right 48%) was found. The ECG showed regression of LBBB. No myocardial biopsy was performed, so it is not possible to get to an unequivocal cardiac dysfunction’s cause. However, the time relationship between the use of AmB and the clinical findings evolution, consistently with the few literature available, suggests a probable diagnosis of AmB toxic cardiomyopathy. An ischaemic cause of the dysfunction is unlikely by the MRI feature and by coronary angiography findings. Literature data suggest that the presence of predisposing factors for cardiac dysfunction, rather than the duration of treatment or preparation used, is the most relevant factor in the development of AmB–related cardiomyopathy. It’s important to perform cardiac monitoring in all patients receiving AmB therapy. In all reported cases, cardiac function recovered substantially after cessation of AmB treatment.

A RARE CASE OF LOEYS–DIETZ SYNDROME: THE IMPORTANCE OF DIAGNOSIS IN PATIENTS UNDERGOING CARDIOVASCULAR SURGERY

Abstract Background Loeys–Dietz syndrome (LDS) is a rare autosomal dominant genetic disorder of connective tissue, characterised by a broad spectrum of craniofacial, vascular (arterial tortuosity and aneurysms) and skeletal clinical signs. Four subtypes have been described, related to mutations in genes encoding for components of the transforming growth factor beta signalling pathway (TGFBR1, TGFBR2, SMAD2, SMAD3, TGFB2 and TGFB3). Diagnosis is based on the evaluation of clinical manifestations and family history. Therefore, many radiologists remain unfamiliar with the imaging and clinical findings in LDS. The Case 75–year–old woman, history of surgery for ruptured gastric a. aneurysm and ectasia of visceral arterial vessels. One year onset of worsening dyspnoea and asthenia, at echocardiography (ECOCG) severe aortic insufficiency has been detected and patient underwent aortic valve replacement with bioprosthesis. Cardiac surgery was complicated by aortic dissection (Stanford A; DeBakey I type) treated with replacement of ascending aorta and anterior hemiarch with tubular prosthesis. On that occasion a family diagnosis of SMAD3 gene mutation was made (both sister and nephew typed), compatible with Loeys–Dietz syndrome type 3. At the control angioTC evidence of proximal and distal anastomosis in order, in the absence of signs of periprosthetic leak. At ECOCG (FE 55%), thickened septum with marked postcardiac dyskinesia. No abnormality detected on ECG. Due to persistence of dyspnoea on mild exertion (NYHA class III) and reduced tolerance to orthostatism, cardiac rehabilitation program was undertaken on an outpatient basis for three months, providing an improvement in exertion tolerance (NYHA II) and a benefit on functional autonomy. LDS is a multisystem connective tissue disorder that is associated with a high burden of complications, a correct diagnosis will allow clinicians to appropriately establish the best therapeutic strategy, especially in cardiac surgery, taking into account the intraoperative and perioperative potential risks.

Soluble biomarkers for Neuromyelitis Optica Spectrum Disorders: a mini review

The Neuromyelitis Optica Spectrum Disorders (NMOSD) constitute a spectrum of rare autoimmune diseases of the central nervous system characterized by episodes of transverse myelitis, optic neuritis, and other demyelinating attacks. Previously thought to be a subtype of multiple sclerosis, NMOSD is now known to be a distinct disease with unique pathophysiology, clinical course, and treatment options. Although there have been significant recent advances in the diagnosis and treatment of NMOSD, the field still lacks clinically validated biomarkers that can be used to stratify disease severity, monitor disease activity, and inform treatment decisions. Here we review many emerging NMOSD biomarkers including markers of cellular damage, neutrophil-to-lymphocyte ratio, complement, and cytokines, with a focus on how each biomarker can potentially be used for initial diagnosis, relapse surveillance, disability prediction, and treatment monitoring.

Multiple endocrine neoplasia type 2B diagnosed after small intestinal volvulus with progressive megacolon in an adolescent.

Multiple endocrine neoplasia type 2B is a rare autosomal dominant disease characterized by the presence of medullary thyroid carcinoma, pheochromocytoma, Marfan-like fatigue, a peculiar face with thickening of the lips, mucosal neuromas on the lips and tongue, and gastrointestinal phenomena. Most patients harbor pathological variants of the RET gene. Herein, we present the first case of a 14year-old boy who experienced small intestinal volvulus along with a megacolon, and he was diagnosed with multiple endocrine neoplasia type 2B. The patient complained of constipation since he was 2years old and slowly progressive abdominal distension at school age. At 14years of age, he presented with remarkable megacolon mimicking Hirschsprung's disease and complicated with small intestinal volvulus. The volvulus was successfully repaired, and the particularly dilated transverse colon was resected following a rectal biopsy. Histopathological evaluation of the resected transverse colon revealed to be compatible with ganglioneuromatosis. After emergency surgery, the patient was diagnosed with multiple endocrine neoplasia type 2B with medullary thyroid carcinoma, and a de novo variant of RET was confirmed. Gastroenterologists should consider it when treating patients with constipation, especially those with megacolon. Therefore, timely diagnosis may lead to appropriate treatment of medullary thyroid carcinoma and improve mortality.

Clinical and genetic characteristics of Chinese patients diagnosed with chronic enteropathy associated with SLCO2A1 gene

Background and aimsChronic enteropathy associated with SLCO2A1 gene is a rare intestinal disease caused by loss-of-function SLCO2A1 mutations, with clinical and genetic characteristics remaining largely unknown, especially in Chinese patients. This study aims to reveal clinical and genetic features of Chinese CEAS patients, highlighting the previously unreported or unemphasized characteristics.MethodsWe enrolled 12 Chinese patients with chronic enteropathy associated with SLCO2A1 gene admitted to Peking Union Medical College Hospital from January 2018 to December 2022. Clinical and genetic data of these patients were collected and analyzed.Results58.3% of patients were male, who also had primary hypertrophic osteoarthropathy, whereas female patients did not have primary hypertrophic osteoarthropathy. Apart from common symptoms associated with anemia and hypoalbuminemia, abdominal pain, ileus, diarrhea, and hematochezia were present. 4 of the 5 female patients had early-onset amenorrhea, though the causal relationship remained to be clarified. Endoscopy and computed tomography enterography revealed that lesions can occur in any part of the digestive tract, most commonly in the ileum. Pathology showed multiple superficial ulcers with adjacent vascular dilatation, and loss of SLCO2A1 expression, particularly in gastrointestinal vascular endothelial cells. Genetic analysis confirmed SLCO2A1 mutations in all patients and identified 11 new SLCO2A1 variants for CEAS.ConclusionsThis study reports new clinical, pathological, and genetic findings in 12 Chinese patients with chronic enteropathy associated with SLCO2A1 gene. This study provides insights into the pathogenesis of this disease. However, studies with larger sample sizes and more in-depth mechanism research are still required.

A novel homozygous RSPH4A variant in a family with primary ciliary dyskinesia and literature review

Introduction: Primary ciliary dyskinesia (PCD) is a rare heterogeneous disease caused by abnormalities in motile cilia. In this case report, we first analyzed the clinical and genetic data of a proband who was suspected of having PCD on the basis of her clinical and radiological findings.Methods: Whole-exome sequencing was performed, and a variant in the RSPH4A gene was identified in the proband. Sanger sequencing was used for validation of RSPH4A variants in the proband, her sister, her daughter and her parents. Finally, the phenotypic features of the patient were analyzed, and the current literature was reviewed to better understand the gene variants in PCD related to hearing loss and the clinical manifestations of the RSPH4A variant in PCD.Results: The chief clinical symptoms of this proband included gradual mixed hearing loss, otitis media, anosmia, sinusitis, recurrent cough and infertility. Her DNA sequencing revealed a novel homozygous T to C transition at position 1321 within exon 3 of RSPH4A according to genetic testing results. This variant had never been reported before. The homozygous variant resulted in an amino acid substitution of tryptophan by arginine at position 441 (p.Trp441Arg). The same variant was also found in the proband’s sister, and a heterozygous pathogenic variant was identified among immediate family members, including the proband’s daughter and parents.Discussion: A literature review showed that 16 pathogenic variants in RSPH4A have been reported. Hearing loss had only been observed in patients with the RSPH4A (c.921+3_6delAAGT) splice site mutation, and the specific type of hearing loss was not described.

Development and validation of a code-based algorithm using in-hospital medical records to identify patients with pulmonary arterial hypertension in the French Healthcare Database

IntroductionPulmonary arterial hypertension (PAH) is a rare and severe disease for which most of the evidence about prognostic factors, evolution and treatment efficacy comes from cohorts, registries and clinical trials. We therefore aimed to develop and validate a new PAH identification algorithm that can be used in the French healthcare database (SNDS).MethodsWe developed and validated the algorithm using the Grenoble Alpes University Hospital medical charts. We first identified PAH patients following a previously validated algorithm (Gillmeyeret al. algorithm), using in hospital ICD-10 codes, right heart catheterisation procedure and PAH specific treatment dispensing. Then, we refined the latter with the exclusion of chronic thromboembolic pulmonary hypertension procedures and treatment, the main misclassification factor. Secondly, we validated this algorithm using a gold standard review of in-hospital medical charts and calculated sensitivity, specificity, positive and negative predictive value (PPV and NPV) and accuracy. Finally, we applied this algorithm in the French healthcare database and described the characteristics of the identified patients.ResultsIn the Grenoble University Hospital, we identified 252 unique patients meeting all the algorithm's criteria between 01/01/2010 and 30/06/2022, and reviewed all medical records. The sensitivity, specificity, PPV, NPV and accuracy were 91.0%, 74.3%, 67.9%, 93.3% and 80.6% respectively. Application of this algorithm to the SNDS yielded the identification of 9931 patients with consistent characteristics compared to PAH registries.ConclusionOverall, we propose a new PAH identification algorithm developed and adapted to the French specificities, that can be used in future studies using the French healthcare database.

Increasing the diagnostic yield of childhood glaucoma cases recruited into the 100,000 Genomes Project

Childhood glaucoma (CG) encompasses a heterogeneous group of genetic eye disorders that is responsible for approximately 5% of childhood blindness worldwide. Understanding the molecular aetiology is key to improving diagnosis, prognosis and unlocking the potential for optimising clinical management. In this study, we investigated 86 CG cases from 78 unrelated families of diverse ethnic backgrounds, recruited into the Genomics England 100,000 Genomes Project (GE100KGP) rare disease cohort, to improve the genetic diagnostic yield. Using the Genomics England/Genomic Medicine Centres (GE/GMC) diagnostic pipeline, 13 unrelated families were solved (13/78, 17%). Further interrogation using an expanded gene panel yielded a molecular diagnosis in 7 more unrelated families (7/78, 9%). This analysis effectively raises the total number of solved CG families in the GE100KGP to 26% (20/78 families). Twenty-five percent (5/20) of the solved families had primary congenital glaucoma (PCG), while 75% (15/20) had secondary CG; 53% of this group had non-acquired ocular anomalies (including iris hypoplasia, megalocornea, ectopia pupillae, retinal dystrophy, and refractive errors) and 47% had non-acquired systemic diseases such as cardiac abnormalities, hearing impairment, and developmental delay. CYP1B1 was the most frequently implicated gene, accounting for 55% (11/20) of the solved families. We identified two novel likely pathogenic variants in the TEK gene, in addition to one novel pathogenic copy number variant (CNV) in FOXC1. Variants that passed undetected in the GE100KGP diagnostic pipeline were likely due to limitations of the tiering process, the use of smaller gene panels during analysis, and the prioritisation of coding SNVs and indels over larger structural variants, CNVs, and non-coding variants.

Andexanet for Factor Xa Inhibitor–Associated Acute Intracerebral Hemorrhage

BackgroundPatients with acute intracerebral hemorrhage who are receiving factor Xa inhibitors have a risk of hematoma expansion. The effect of andexanet alfa, an agent that reverses the effects of factor Xa inhibitors, on hematoma volume expansion has not been well studied.MethodsWe randomly assigned, in a 1:1 ratio, patients who had taken factor Xa inhibitors within 15 hours before having an acute intracerebral hemorrhage to receive andexanet or usual care. The primary end point was hemostatic efficacy, defined by expansion of the hematoma volume by 35% or less at 12 hours after baseline, an increase in the score on the National Institutes of Health Stroke Scale of less than 7 points (scores range from 0 to 42, with higher scores indicating worse neurologic deficit) at 12 hours, and no receipt of rescue therapy between 3 hours and 12 hours. Safety end points were thrombotic events and death.ResultsA total of 263 patients were assigned to receive andexanet, and 267 to receive usual care. Efficacy was assessed in an interim analysis that included 452 patients, and safety was analyzed in all 530 enrolled patients. Atrial fibrillation was the most common indication for factor Xa inhibitors. Of the patients receiving usual care, 85.5% received prothrombin complex concentrate. Hemostatic efficacy was achieved in 150 of 224 patients (67.0%) receiving andexanet and in 121 of 228 (53.1%) receiving usual care (adjusted difference, 13.4 percentage points; 95% confidence interval [CI], 4.6 to 22.2; P=0.003). The median reduction from baseline to the 1-to-2-hour nadir in anti–factor Xa activity was 94.5% with andexanet and 26.9% with usual care (P<0.001). Thrombotic events occurred in 27 of 263 patients (10.3%) receiving andexanet and in 15 of 267 (5.6%) receiving usual care (difference, 4.6 percentage points; 95% CI, 0.1 to 9.2; P=0.048); ischemic stroke occurred in 17 patients (6.5%) and 4 patients (1.5%), respectively. There were no appreciable differences between the groups in the score on the modified Rankin scale or in death within 30 days.ConclusionsAmong patients with intracerebral hemorrhage who were receiving factor Xa inhibitors, andexanet resulted in better control of hematoma expansion than usual care but was associated with thrombotic events, including ischemic stroke. (Funded by Alexion AstraZeneca Rare Disease and others; ANNEXA-I ClinicalTrials.gov number, NCT03661528.)

Fibroblasts’ secretome from calcified and non-calcified dermis in Pseudoxanthoma elasticum differently contributes to elastin calcification

Pseudoxanthoma elasticum (PXE) is a rare disease characterized by ectopic calcification, however, despite the widely spread effect of pro/anti-calcifying systemic factors associated with this genetic metabolic condition, it is not known why elastic fibers in the same patient are mainly fragmented or highly mineralized in clinically unaffected (CUS) and affected (CAS) skin, respectively. Cellular morphology and secretome are investigated in vitro in CUS and CAS fibroblasts. Here we show that, compared to CUS, CAS fibroblasts exhibit: a) differently distributed and organized focal adhesions and stress fibers; b) modified cell-matrix interactions (i.e., collagen gel retraction); c) imbalance between matrix metalloproteinases and tissue inhibitor of metalloproteinases; d) differentially expressed pro- and anti-calcifying proteoglycans and elastic-fibers associated glycoproteins. These data emphasize that in the development of pathologic mineral deposition fibroblasts play an active role altering the stability of elastic fibers and of the extracellular matrix milieu creating a local microenvironment guiding the level of matrix remodeling at an extent that may lead to degradation (in CUS) or to degradation and calcification (in CAS) of the elastic component. In conclusion, this study contributes to a better understanding of the mechanisms of the mineral deposition that can be also associated with several inherited or age-related diseases (e.g., diabetes, atherosclerosis, chronic kidney diseases).