Zhongguo Dang Dai Er Ke Za Zhi. 2023 Apr 15;25(4):401-407. doi: 10.7499/j.issn.1008-8830.2211062.

ABSTRACT

A boy, aged 16 months, attended the hospital due to head and facial erythema for 15 months and vulva erythema for 10 months with aggravation for 5 days. The boy developed perioral and periocular erythema in the neonatal period and had erythema and papules with desquamation and erosion in the neck, armpit, and trigone of vulva in infancy. Blood gas analysis showed metabolic acidosis; the analysis of amino acid and acylcarnitine profiles for inherited metabolic diseases and the analysis of organic acid in urine suggested multiple carboxylase deficiency; genetic testing showed a homozygous mutation of c.1522C>T(p.R508W) in the HLCS gene. Finally the boy was diagnosed with holocarboxylase synthetase deficiency and achieved a good clinical outcome after oral biotin treatment. This article analyzes the clinical data of a child with holocarboxylase synthetase deficiency and summarizes the etiology, diagnosis, and treatment of this child, so as to provide ideas for clinicians to diagnose this rare disease.

PMID:37073846 | DOI:10.7499/j.issn.1008-8830.2211062

J Med Case Rep. 2023 Apr 15;17(1):139. doi: 10.1186/s13256-023-03885-2.

ABSTRACT

BACKGROUND: Botulism is a rare neuroparalytic disease that has only presented itself 19 times in the last 30 years in Belgium. Patients present to emergency services with a wide range of complaints. Foodborne botulism is a forgotten yet life-threatening disease.

CASE PRESENTATION: We describe a case of a Caucasian female in her 60s that presented to the emergency with reflux with nausea and spasmodic epigastric pain, no vomiting, dry mouth, and weakness in both legs. The symptoms started after ingestion of Atlantic wolffish. After exclusion of other more common causes, foodborne botulism was suspected. The patient was admitted to the intensive care unit for mechanical ventilation. Following treatment with trivalent botulinum antitoxin, she made a full neurologic recovery.

CONCLUSION: It is important to rapidly recognize the possible diagnosis of botulism even if the neurological symptoms are not dominant. Rapid neurologic dysfunction and respiratory difficulties starts between 6 and 72 hours after ingestion. The decision to administer antitoxins should, however, be based on the presumptive clinical diagnosis and diagnosis should not delay therapy.

PMID:37060100 | PMC:PMC10105410 | DOI:10.1186/s13256-023-03885-2

Orphanet J Rare Dis. 2023 Apr 14;18(1):82. doi: 10.1186/s13023-023-02669-7.

ABSTRACT

BACKGROUND: Centers for rare diseases serve as contact points for patients with complex, often undiagnosed complaints and persistent somatic symptoms of heterogeneous origin. Little is known about psychological distress of patients consulting these centers.

OBJECTIVES: To better understand psychological distress of adult patients presenting at a center for rare diseases by determining the proportion of patients screening positive for depressive, anxiety, and somatic symptom disorders (SSD) and to identify factors associated with increased psychopathology.

METHODS: Cross-sectional data from the routine care registry of the Martin Zeitz Center for Rare Diseases (MZCSE) at the University Medical Center Hamburg-Eppendorf in Germany was retrieved and analyzed. We included all adult patients presenting between October 01,2020 and September 30,2021, who gave written informed consent.

MEASURES: Sociodemographic variables, medical history and healthcare utilization, as well as validated measures to screen for a depressive disorder (PHQ-8), an anxiety disorder (GAD-7), and SSD (PHQ-15, SSD-12).

RESULTS: N = 167 patients were included (age 44.5 ± 14.3 years, 64.7% female). A total of 40.7% of the patients screened positive for a depressive disorder (PHQ-8 ≥ 10), 27.5% for an anxiety disorder (GAD-7 ≥ 10) and 45.0% screened positive for SSD (PHQ-15 ≥ 9 & SSD-12 ≥ 23). Factors associated with increased psychopathology included the number of symptoms, the number of different specialties consulted before and past psychotherapy.

CONCLUSIONS: Patients presenting at centers for rare diseases are likely to experience high rates of psychological distress. Systematically screening patients with rare and undiagnosed diseases for mental disorders can help to detect those at risk at an early stage and initiate adequate psychological care.

PMID:37060005 | PMC:PMC10103043 | DOI:10.1186/s13023-023-02669-7

Bone. 2023 Apr 12:116763. doi: 10.1016/j.bone.2023.116763. Online ahead of print.

ABSTRACT

X-linked hypophosphatemia is the most common cause of inherited rickets, due to inactivating variants of PHEX. More than 800 variants have been described to date and one which consists of a single base change in the 3' untranslated region (UTR) (c.*231A>G) is reported as prevalent in North America. Recently an exon 13-15 duplication has been found to occur in concert with the c.*231A>G variant, and thus it is unclear whether the pathogenicity is solely a function of the UTR variant. We present a family with XLH who harbors the exon 13-15 duplication but does not carry the 3'UTR variant, providing evidence that the duplication itself is the pathogenic variant when these two variants are found in cis.

PMID:37059315 | DOI:10.1016/j.bone.2023.116763

Nat Genet. 2023 Apr;55(4):524. doi: 10.1038/s41588-023-01380-4.

NO ABSTRACT

PMID:37055647 | DOI:10.1038/s41588-023-01380-4

Fortschr Neurol Psychiatr. 2023 Apr;91(4):126-127. doi: 10.1055/a-2022-4203. Epub 2023 Apr 13.

NO ABSTRACT

PMID:37055012 | DOI:10.1055/a-2022-4203

Int J Environ Res Public Health. 2023 Mar 28;20(7):5296. doi: 10.3390/ijerph20075296.

ABSTRACT

Erythropoietic protoporphyria (EPP) is an ultra-rare inborn error of metabolism characterised by painful phototoxic burn injuries after short exposure times to visible light. Patients with EPP are highly adapted to their condition which makes the quantification of their health-related quality of life (QoL) challenging. In the presented patient-initiated feasibility study, we describe a new approach to assess treatment benefits in EPP by measuring QoL with the generic EQ-5D instrument in five patients under long-term (≥two years) treatment with afamelanotide, the first approved therapy for EPP. For the study, we selected patients with EPP who in addition were affected by an involuntary treatment interruption (caused by a temporary reimbursement suspension) because we hypothesized that individuals who had previously unlearned their adaptation are better able to assess their life without treatment than treatment-naïve patients. QoL under treatment was comparable to the age-matched population norm, and retrospective results for a treatment interruption and phototoxic reaction time point were comparable to the QoL of patients with chronic neuropathic pain and acute burn injuries, respectively. The results were accepted by the National Institute for Health and Care Excellence in England for their evaluation of the cost-effectiveness of afamelanotide, i.e., the calculation of quality-adjusted life years.

PMID:37047912 | DOI:10.3390/ijerph20075296

N Engl J Med. 2023 Apr 27;388(17):1559-1571. doi: 10.1056/NEJMoa2209046. Epub 2023 Apr 12.

ABSTRACT

BACKGROUND: Pediatric disorders include a range of highly penetrant, genetically heterogeneous conditions amenable to genomewide diagnostic approaches. Finding a molecular diagnosis is challenging but can have profound lifelong benefits.

METHODS: We conducted a large-scale sequencing study involving more than 13,500 families with probands with severe, probably monogenic, difficult-to-diagnose developmental disorders from 24 regional genetics services in the United Kingdom and Ireland. Standardized phenotypic data were collected, and exome sequencing and microarray analyses were performed to investigate novel genetic causes. We developed an iterative variant analysis pipeline and reported candidate variants to clinical teams for validation and diagnostic interpretation to inform communication with families. Multiple regression analyses were performed to evaluate factors affecting the probability of diagnosis.

RESULTS: A total of 13,449 probands were included in the analyses. On average, we reported 1.0 candidate variant per parent-offspring trio and 2.5 variants per singleton proband. Using clinical and computational approaches to variant classification, we made a diagnosis in approximately 41% of probands (5502 of 13,449). Of 3599 probands in trios who received a diagnosis by clinical assertion, approximately 76% had a pathogenic de novo variant. Another 22% of probands (2997 of 13,449) had variants of uncertain significance in genes that were strongly linked to monogenic developmental disorders. Recruitment in a parent-offspring trio had the largest effect on the probability of diagnosis (odds ratio, 4.70; 95% confidence interval [CI], 4.16 to 5.31). Probands were less likely to receive a diagnosis if they were born extremely prematurely (i.e., 22 to 27 weeks' gestation; odds ratio, 0.39; 95% CI, 0.22 to 0.68), had in utero exposure to antiepileptic medications (odds ratio, 0.44; 95% CI, 0.29 to 0.67), had mothers with diabetes (odds ratio, 0.52; 95% CI, 0.41 to 0.67), or were of African ancestry (odds ratio, 0.51; 95% CI, 0.31 to 0.78).

CONCLUSIONS: Among probands with severe, probably monogenic, difficult-to-diagnose developmental disorders, multimodal analysis of genomewide data had good diagnostic power, even after previous attempts at diagnosis. (Funded by the Health Innovation Challenge Fund and Wellcome Sanger Institute.).

PMID:37043637 | PMC:PMC7614484 | DOI:10.1056/NEJMoa2209046

Kathmandu Univ Med J (KUMJ). 2022 Jul-Sep;20(79):391-395.

ABSTRACT

Fraser syndrome (FS, MIM 219000) is a rare autosomal disorder characterized by systemic and oro-facial malformation, usually comprising cryptophthalmos, laryngeal malformations, syndactyly, and urogenital defects. We presented a 21-year-old FS case with partial missing teeth seeking aesthetic dental treatment. Clinical examination revealed bilateral cryptophthalmos, extensive syndactyly of hands and feet broad nose with the depressed nasal bridge, and surgically corrected bilateral cleft lip. She presented class III jaw relation and reduced the vertical height of the face. Prosthetic rehabilitation of the patient was done with upper and lower overlay dentures made from acrylic resin (VIPI BLOCK TRILUX®, VIPI Industria, Pirassununga, SP, Brazil) using computer-aided design (CAD) and computer-aided manufacturing (CAM) process. At the follow-up visit, the patient presented improved aesthetics and function. Proper management and rehabilitation of FS patients are challenging, but standard guidelines for oral health management are currently lacking. This article presents a case of Fraser syndrome presenting oral and craniofacial anomalies, and prosthetic rehabilitation was done. We also provided recommendations for the optimal oral health care for the FS patients. Functional adaptation and rehabilitation have significant roles in the various functions, survival, and quality of the life of FS patients. Integrated medicaldental care is needed in such patients with support from family members, friends, and colleagues.

PMID:37042386

Orphanet J Rare Dis. 2023 Apr 11;18(1):79. doi: 10.1186/s13023-023-02693-7.

ABSTRACT

BACKGROUND: Traditional clinical trials require tests and procedures that are administered in centralized clinical research sites, which are beyond the standard of care that patients receive for their rare and chronic diseases. The limited number of rare disease patients scattered around the world makes it particularly challenging to recruit participants and conduct these traditional clinical trials.

MAIN BODY: Participating in clinical research can be burdensome, especially for children, the elderly, physically and cognitively impaired individuals who require transportation and caregiver assistance, or patients who live in remote locations or cannot afford transportation. In recent years, there is an increasing need to consider Decentralized Clinical Trials (DCT) as a participant-centric approach that uses new technologies and innovative procedures for interaction with participants in the comfort of their home.

CONCLUSION: This paper discusses the planning and conduct of DCTs, which can increase the quality of trials with a specific focus on rare diseases.

PMID:37041605 | PMC:PMC10088572 | DOI:10.1186/s13023-023-02693-7

Orphanet J Rare Dis. 2023 Apr 11;18(1):75. doi: 10.1186/s13023-023-02678-6.

ABSTRACT

BACKGROUND: There are approximately 10,000 rare diseases that affect around 30,000,000 individuals in the U.S.A., most of which do not have an FDA-approved treatment. This fact highlights the failure of traditional research approaches to overcome the unique challenges of developing rare disease treatments. The Castleman Disease Collaborative Network was founded in 2012 to advance research and treatments for Castleman disease, a rare and deadly disease that involves the immune system attacking the body's vital organs for an unknown cause. It has spearheaded a novel strategy for advancing biomedical research, the Collaborative Network Approach. This approach consists of eight steps, one of which is to identify and prioritize high-impact research questions through crowdsourcing ideas from the entire community of stakeholders: patients, loved ones, physicians, and researchers. Rather than hoping that the right researcher will apply for the right research project at the right time, crowdsourcing high-priority research projects into a research strategy ensures that the most high-impact, patient-centered studies are prioritized. The Castleman Disease Collaborative Network launched an initiative in 2021 to systematically generate this list of community-directed studies to focus Castleman disease research efforts.

RESULTS: The Castleman Disease Collaborative Network was able to successfully create a patient-centered research agenda through engaging the entire community of stakeholders. The community contributed important questions about Castleman disease, which were prioritized and reviewed by our Scientific Advisory Board, and the result was a finalized list of studies that address these prioritized questions. We were also able to generate a best practices list which can serve as a model that can be utilized for other rare diseases.

CONCLUSION: Creating a patient-centered research agenda through crowdsourcing research ideas from the community is one of the most important ways that the Castleman Disease Collaborative Network operationalizes its commitment to keeping patients at the center of research and we hope that by sharing these insights we can assist other rare disease organizations to pursue a patient-centric approach.

PMID:37041585 | PMC:PMC10091676 | DOI:10.1186/s13023-023-02678-6

Mediterr J Rheumatol. 2022 Dec 31;33(4):437-443. doi: 10.31138/mjr.33.4.437. eCollection 2022 Dec.

ABSTRACT

BACKGROUND: Anti-Jo1 syndrome is one of the most common amongst the various anti synthetase syndromes (ASS), which forms a subgroup of the idiopathic inflammatory myositis (IIM). It is characterised by myositis, interstitial lung disease (ILD), fever, Raynaud's phenomenon, and mechanic's hands; associated with the presence of anti-Jo1 antibodies in serum. Being an orphan disease, the clinical diagnosis is often delayed.

MATERIALS AND METHODS: In this retrospective study, all patients diagnosed as Anti-Jo1 syndrome, from two tertiary care hospitals in Western Maharashtra, between 01 January 2019 - 31 December 2020, were enrolled. The parameters studied included demographic data, clinical features at presentation, laboratory parameters, spirometry, and radiographic findings, along with treatment instituted.

RESULT: A total of 17 patients (8 males, 9 females) qualified for inclusion in the study. The mean age of diagnosis was 40 (±13) years with mean time to diagnosis being 2 years (± 0.6 years), from first clinical presentation. The most common presenting symptoms encountered were arthritis (n = 12, 70.5%), fever (n = 16, 70.5%), myositis (n=11, 64.7%) and breathlessness (n=10, 58.8%).10 patients had ILD at presentation on high resolution computerised tomography of chest (n=10, 58.8%) with restrictive lung defect on spirometry. Six patients required induction of immunosuppression using pulse methylprednisolone (n=6) and Rituximab (n=6), while 11 were managed with oral steroids. Mycophenolate mofetil (n=10) and Azathioprine (n=7) were used as maintenance immunosuppression.

CONCLUSION: Anti-Jo1 syndrome is a myositis syndrome, presenting with a multitude of clinical features. Steroids and disease modifying anti rheumatic drugs form mainstay of therapy.

PMID:37034360 | PMC:PMC10075366 | DOI:10.31138/mjr.33.4.437

Orphanet J Rare Dis. 2023 Apr 10;18(1):73. doi: 10.1186/s13023-023-02695-5.

ABSTRACT

INTRODUCTION: The Undiagnosed Diseases Network (UDN), a clinical research study funded by the National Institutes of Health, aims to provide answers for patients with undiagnosed conditions and generate knowledge about underlying disease mechanisms. UDN evaluations involve collaboration between clinicians and researchers and go beyond what is possible in clinical settings. While medical and research outcomes of UDN evaluations have been explored, this is the first formal assessment of the patient and caregiver experience.

METHODS: We invited UDN participants and caregivers to participate in focus groups via email, newsletter, and a private participant Facebook group. We developed focus group questions based on research team expertise, literature focused on patients with rare and undiagnosed conditions, and UDN participant and family member feedback. In March 2021, we conducted, recorded, and transcribed four 60-min focus groups via Zoom. Transcripts were evaluated using a thematic analysis approach.

RESULTS: The adult undiagnosed focus group described the UDN evaluation as validating and an avenue for access to medical providers. They also noted that the experience impacted professional choices and helped them rely on others for support. The adult diagnosed focus group described the healthcare system as not set up for rare disease. In the pediatric undiagnosed focus group, caregivers discussed a continued desire for information and gratitude for the UDN evaluation. They also described an ability to rule out information and coming to terms with not having answers. The pediatric diagnosed focus group discussed how the experience helped them focus on management and improved communication. Across focus groups, adults (undiagnosed/diagnosed) noted the comprehensiveness of the evaluation. Undiagnosed focus groups (adult/pediatric) discussed a desire for ongoing communication and care with the UDN. Diagnosed focus groups (adult/pediatric) highlighted the importance of the diagnosis they received in the UDN. The majority of the focus groups noted a positive future orientation after participation.

CONCLUSION: Our findings are consistent with prior literature focused on the patient experience of rare and undiagnosed conditions and highlight benefits from comprehensive evaluations, regardless of whether a diagnosis is obtained. Focus group themes also suggest areas for improvement and future research related to the diagnostic odyssey.

PMID:37032333 | PMC:PMC10084693 | DOI:10.1186/s13023-023-02695-5

J Biomed Inform. 2023 May;141:104338. doi: 10.1016/j.jbi.2023.104338. Epub 2023 Apr 5.

ABSTRACT

Federated learning initiatives in healthcare are being developed to collaboratively train predictive models without the need to centralize sensitive personal data. GenoMed4All is one such project, with the goal of connecting European clinical and -omics data repositories on rare diseases through a federated learning platform. Currently, the consortium faces the challenge of a lack of well-established international datasets and interoperability standards for federated learning applications on rare diseases. This paper presents our practical approach to select and implement a Common Data Model (CDM) suitable for the federated training of predictive models applied to the medical domain, during the initial design phase of our federated learning platform. We describe our selection process, composed of identifying the consortium's needs, reviewing our functional and technical architecture specifications, and extracting a list of business requirements. We review the state of the art and evaluate three widely-used approaches (FHIR, OMOP and Phenopackets) based on a checklist of requirements and specifications. We discuss the pros and cons of each approach considering the use cases specific to our consortium as well as the generic issues of implementing a European federated learning healthcare platform. A list of lessons learned from the experience in our consortium is discussed, from the importance of establishing the proper communication channels for all stakeholders to technical aspects related to -omics data. For federated learning projects focused on secondary use of health data for predictive modeling, encompassing multiple data modalities, a phase of data model convergence is sorely needed to gather different data representations developed in the context of medical research, interoperability of clinical care software, imaging, and -omics analysis into a coherent, unified data model. Our work identifies this need and presents our experience and a list of actionable lessons learned for future work in this direction.

PMID:37023843 | DOI:10.1016/j.jbi.2023.104338

Swiss Med Wkly. 2023 Mar 31;153:40048. doi: 10.57187/smw.2023.40048.

ABSTRACT

AIMS OF THE STUDY: Acquired haemophilia A is a rare disease with an annual incidence of 1.48 per million. Based on clinical observations, we suspect a higher incidence in southern Switzerland, and aimed at providing local epidemiological data, and clinical information regarding diagnosis, treatment and outcome in our region.

METHODS: All adult patients with acquired haemophilia A treated between 2013 and 2019 in our facility were included in the present retrospective analysis.

RESULTS: We treated 11 patients with acquired haemophilia A between 2013 and 2019, resulting in an annual incidence of 4.5 per million (95% confidence interval [CI] 0-9.0). Median delay from first symptoms to diagnosis was 4.5 days, and the median age at diagnosis was 79 years (range 23-87). Possible causative conditions were: pregnancy (n = 1), polyarteritis nodosa (n = 1), myelodysplastic syndrome (n = 1), chronic human immunodeficiency virus (HIV) (n = 1), and HIV postexposure prophylaxis (n = 1). In five patients no underlying or associated condition was identified. Median activated partial thromboplastin time (aPTT)) at baseline was 79 seconds (65-117; ref. value <38 sec), and FVIII:C 2.15% (<1-3.75%). A FVIII:C <1% was present in 4/10 patients. Median FVIII-inhibitor titre was 10.3 BU/ml (2.4-75.0 BU/ml). All patients had bleeding symptoms, 5/10 patients had major bleedings, and 7/10 patients were treated with bypassing agents. All patients received corticosteroids; 7/10 patients received immunosuppressive combination therapy. FVIII levels of ≥50% were achieved after a median of 40 days (8-62). One patient had a severe immunosuppressive therapy-related infection. An 87-years-old woman died for reasons not related to acquired haemophilia A or immunosuppressive therapy.

CONCLUSIONS: Acquired haemophilia A is a rare disease, but manageable despite the advanced patient age and comorbidities. Its incidence in Southern Switzerland is higher than previously suspected.

PMID:37021783 | DOI:10.57187/smw.2023.40048

Orphanet J Rare Dis. 2023 Apr 5;18(1):71. doi: 10.1186/s13023-023-02685-7.

ABSTRACT

BACKGROUND: In many countries worldwide orphan drug regulations are installed but only the United States of America and Japan have an orphan device regulation. For many years surgeons have used off-label or self-assembled medical devices for the prevention, diagnosis or treatment of rare disorders. Four examples are given: an external cardiac pacemaker, a metal brace for clubfoot in newborns, a transcutaneous nerve stimulator and a cystic fibrosis mist tent.

CONCLUSION: In this article we argue that we need authorized medical devices as well as medicinal products to prevent, diagnose and treat patients with life-threatening or chronically debilitating disorders with a low prevalence/incidence. Several arguments are given to support this statement.

PMID:37020310 | PMC:PMC10077604 | DOI:10.1186/s13023-023-02685-7

PLoS One. 2023 Apr 5;18(4):e0281892. doi: 10.1371/journal.pone.0281892. eCollection 2023.

ABSTRACT

BACKGROUND: Genotype-phenotype analyses of rare diseases often suffer from a lack of power, due to small sample size, which makes identifying significant associations difficult. Sinusoidal obstruction syndrome (SOS) of the liver is a rare but life-threatening complication of hematopoietic stem cell transplantation (HSCT). The alkylating agent busulfan is commonly used in HSCT and known to trigger SOS. We developed a novel pipeline to identify genetic determinants in rare diseases by combining in vitro information with clinical whole-exome sequencing (WES) data and applied it in SOS patients and controls.

METHODS: First, we analysed differential gene expression in six lymphoblastoid cell lines (LCLs) before and after incubation with busulfan. Second, we used WES data from 87 HSCT patients and estimated the association with SOS at the SNP and the gene levels. We then combined the results of the expression and the association analyses into an association statistic at the gene level. We used an over-representation analysis to functionally characterize the genes that were associated with a significant combined test statistic.

RESULTS: After treatment of LCLs with busulfan, 1708 genes were significantly up-, and 1385 down-regulated. The combination of the expression experiment and the association analysis of WES data into a single test statistic revealed 35 genes associated with the outcome. These genes are involved in various biological functions and processes, such as "Cell growth and death", "Signalling molecules and interaction", "Cancer", and "Infectious disease".

CONCLUSIONS: This novel data analysis pipeline integrates two independent omics datasets and increases statistical power for identifying genotype-phenotype associations. The analysis of the transcriptomics profile of cell lines treated with busulfan and WES data from HSCT patients allowed us to identify potential genetic contributors to SOS. Our pipeline could be useful for identifying genetic contributors to other rare diseases where limited power renders genome-wide analyses unpromising.

TRIAL REGISTRATION: For the clinical dataset: Clinicaltrials.gov: NCT01257854. https://clinicaltrials.gov/ct2/history/NCT01257854.

PMID:37018234 | PMC:PMC10075428 | DOI:10.1371/journal.pone.0281892

J Palliat Med. 2023 Apr;26(4):599-600. doi: 10.1089/jpm.2022.0521.

NO ABSTRACT

PMID:37011294 | DOI:10.1089/jpm.2022.0521

Mol Genet Metab. 2023 Apr;138(4):107558. doi: 10.1016/j.ymgme.2023.107558. Epub 2023 Mar 8.

ABSTRACT

Urea cycle disorders (UCDs) are a group of rare inherited metabolic diseases caused by a deficiency of one of the enzymes or transporters that constitute the urea cycle. Defects in these enzymes lead to acute accumulation (hyperammonemic crises, HAC) or chronically elevated levels (hyperammonemia) of ammonia in the blood and/or various tissues including the brain, which can cause persistent neurological deficits, irreversible brain damage, coma, and death. Ongoing treatment of UCDs include the use of nitrogen-scavenging agents, such as sodium phenylbutyrate (salt of 4-phenylbutyric acid; NaPBA) or glycerol phenylbutyrate (GPB). These treatments provide an alternative pathway for nitrogen disposal through the urinary excretion of phenylacetylglutamine. ACER-001 is a novel formulation of NaPBA with polymer coated pellets in suspension, which is designed to briefly mask the unpleasant bitter taste of NaPBA and is being developed as a treatment option for patients with UCDs. Four Phase 1 studies were conducted to characterize the bioavailability (BA) and/or bioequivalence (BE) of ACER-001 (in healthy volunteers) and taste assessment relative to NaPBA powder (in taste panelists). ACER-001 was shown to be bioequivalent to NaPBA powder under both fed and fasting conditions. Lower systemic exposure of phenylacetate (PAA) and phenylbutyrate (PBA) was observed when ACER-001 was administered with a high-fat meal relative to a fasting state suggesting that the lower doses of PBA administered under fasting conditions may yield similar efficacy with potentially fewer dose dependent adverse effects relative to higher doses with a meal. ACER-001 appeared to be adequately taste-masked, staying below the aversive taste threshold for the first 3 min after the formulation was prepared and remaining palatable when taken within 5 min.

PMID:37004302 | DOI:10.1016/j.ymgme.2023.107558

BMC Musculoskelet Disord. 2023 Mar 31;24(1):247. doi: 10.1186/s12891-023-06371-4.

ABSTRACT

BACKGROUND: Progressive osseous heteroplasia (POH) is a rare genetic condition that causes progressive ossification. This usually results from an inactivating mutation of the paternal GNAS gene. Herein, we report a case of POH caused by a novel mutation in exon 2 of the GNAS gene.

CASE PRESENTATION: A 5-year-old Chinese boy was referred to our hospital for a growing mass in his right foot. Although laboratory findings were normal, radiographic imaging revealed severe ossification in his right foot and smaller areas of intramuscular ossification in his arms and legs. A de novo mutation (c.175C > T, p.Q59X) in exon 2 of the GNAS gene was identified, prompting a diagnosis of POH. We conducted a systematic literature review to better understand this rare disease.

CONCLUSION: We have discovered that a de novo nonsense mutation in exon 2 of GNAS can lead to POH. Our literature review revealed that ankylosis of the extremities is the primary clinical outcome in patients with POH. Unlike other conditions such as fibrodysplasia ossificans progressiva (FOP), patients with POH do not experience respiratory failure. However, much remains to be learned about the relationship between the type of GNAS gene mutation and the resulting POH symptoms. Further research is needed to understand this complex and rare disease. This case adds to our current understanding of POH and will contribute to future studies and treatments.

PMID:37003989 | PMC:PMC10064707 | DOI:10.1186/s12891-023-06371-4