In recent years, China has increased attention on the issue of rare diseases, and the government has promulgated rare disease–related policies to gradually improve rare disease diagnosis, treatment, drug marketing, and patient burden. Orphan drugs were added to the medical insurance directory in 7 batches, of which 22 drugs were first included in the 2004 medical insurance directory and 8, 16, 12, 7, 8, and 7 were included in the 2009, 2017, 2019, 2020, 2021, and 2022 versions, respectively. Currently, 106 orphan drugs are marketed in China, which are suitable for treating 53 rare diseases such as hematologic diseases, congenital metabolism disorders, neuropathies, and digestive system diseases and for other treatment fields. The drugs are mainly manufactured in 15 countries such as China, Switzerland, and the USA, of which 10 drugs can be used to treat different rare diseases. At the same time, there are multiple treatments available for 25 rare diseases. In this paper, we examined the manufacturers, marketing status, indications, and inclusion of orphan drugs in the National Basic Medical Insurance Directory to describe and analyze the current status of 106 orphan drugs that are currently marketed in China to provide a reference for rare disease policy formulation and drug development.
Ortner's syndrome (OS), also called cardiovocal syndrome, is a rare condition hallmarked by left recurrent laryngeal nerve palsy due to underlying cardiopulmonary disease. The purpose of this review is to systemically analyze the existing literature for cases of OS to outline typical presentation, methods of diagnosis, and management of these patients. Case reports, case series, and cohort studies describing OS between 1955 and 2021 were identified. Individual manuscripts were reviewed for clinical features, presentation, and management. A total of 117 patient cases were gathered from 92 published articles. Common symptoms included hoarseness, dyspnea, cough, and dysphagia. The most common associated comorbidity was aortic aneurysm (41%), followed by pulmonary hypertension (35%), mitral stenosis (17%), and hypertension (12%). Among those who were managed via surgical intervention, 85.4% reported improvement in their hoarseness. While historically OS was associated with mitral stenosis, in recent decades, aortic aneurysms and dilation of the pulmonary artery from pulmonary hypertension have emerged as primary etiologies of OS. Therefore, OS should be considered in any patient presenting with hoarseness and history of cardiopulmonary disease. Surgical intervention in appropriate candidates resolves OS in most cases.
Rare diseases are diseases that occur at low prevalence, and most of them are chronic and serious diseases that are often life-threatening. Currently, there is no unified definition for rare diseases. The diagnosis, treatment, and research of rare diseases have become the focus of medicine and biopharmacology, as well as the breakthrough point of clinical and basic research. Birth defects are the hard-hit area of rare diseases and the frontiers of its research. Since most of these defects have a genetic basis, early screening and diagnosis have important scientific value and social significance for the prevention and control of such diseases. At present, there is no effective treatment for most rare diseases, but progress in prenatal diagnosis and screening can prevent the occurrence of diseases and help prevent and treat rare diseases. This article discusses the progress in genetic-related birth defects and rare diseases.
Effective control of rare diseases requires health programs based on principles of protection and prevention. Carrier screening programs serve as preventive measures by identifying at-risk groups. This review examines the impact, implementation, advantages, and disadvantages of carrier screening, incorporating examples from ten countries: the United States, Canada, the United Kingdom, Israel, China, Australia, Italy, Germany, the Netherlands, and Turkey. Data on carrier screening and related policies were collected from July to November 2022 and presented in a tabular format using a coding system devised by the authors. Variability was observed in the diseases/disorders and populations screened, screening expenses, and government provision across the countries. The number of diseases/disorders examined, ranging from 3 to 47, was determined by committee guidelines, government resources, pilot studies, and national institute resources. Notably, carrier screening programs exhibited greater worldwide inconsistency compared to newborn screening programs. The comparative analysis of developed countries serves to guide emerging nations. To address inequalities at both local and global levels, there is a need to enhance the establishment, development, and implementation of carrier screening programs. Furthermore, cost analyses of screening should be conducted, and adequate funding should be allocated to countries. In conclusion, this review highlights the preventive potential of carrier screening for rare diseases and emphasizes the importance of improving carrier screening programs globally to achieve equitable healthcare outcomes.
VEXAS syndrome, is a hemato-inflammatory chronic disease characterized with predominantly rheumatic and hematologic systemic involvement. It was first described in 2020 by a group of researchers in the United States. VEXAS syndrome is a rare condition that primarily affects adult males and is caused by a mutation in the UBA1 gene located on the X chromosome. Its pathogenesis is related to the somatic mutation affecting methionine-41 (p.Met41) in UBA1, the major E1 enzyme that initiates ubiquitylation. Mutant gene lead to decreased ubiquitination and activated innate immune pathways and systemic inflammation occur. The specific mechanism by which the UBA1 mutation leads to the clinical features of VEXAS syndrome is not yet fully understood. VEXAS is a newly define adult-onset inflammatory syndrome manifested with treatment-refractory fevers, arthritis, chondritis, vasculitis, cytopenias, typical vacuoles in hematopetic precursor cells, neutrophilic cutaneous and pulmonary inflammation. Diagnosing VEXAS syndrome can be challenging due to its rarity and the overlap of symptoms with other inflammatory conditions. Genetic testing to identify the UBA1 gene mutation is essential for definitive diagnosis. Currently, there is no known cure for VEXAS syndrome, and treatment mainly focuses on managing the symptoms. This may involve the use of anti-inflammatory medications, immunosuppressive drugs, and supportive therapies tailored to the individual patient's needs. Due to the recent discovery of VEXAS syndrome, ongoing research is being conducted to better understand its pathogenesis, clinical features, and potential treatment options. In this review article, the clinical, diagnostic and treatment approaches of VEXAS syndrome were evaluated in the light of the latest literature data.
Interferon-induced transmembrane proteins (IFITMs 1, 2, and 3) play a critical role in preventing pathogen infection in vertebrates. They are also involved in the occurrence and prognosis of cancer. Myogenesis is a complex process regulated by several factors. This study disclosed that Ifitm1–3 were upregulated in the process of myogenic differentiation of C2C12 myoblasts on days 3, 5, and 7. This positively correlated with the expression of differentiation factors MyoD, myogenin, Mrf5, and desmin. Furthermore, knockdown of Ifitm1–3 by their individual siRNAs inhibited myogenesis of C2C12 myoblasts, with relative downregulation of MyoD, myogenin, Mrf5, and desmin. Subsequently, myotube formation and fusion percentage decreased. Co-immunoprecipitation combined with LC-MS/MS analysis uncovered the interaction proteins of IFITM1 and IFITM3 in C2C12 myoblasts. A total of 84 overlapped interaction proteins of IFITM1 and IFITM3 were identified, and one of the clusters was engaged in cytoskeletal and sarcomere proteins, including desmin, myosin, actin, vimentin, nestin, ankycorbin, and nucleolin. Hence, we hypothesize that these interacting proteins may function as scaffolds for IFITM1–3, possibly through the interaction protein desmin to initiate further interaction with other proteins to participate in myogenesis; however, the molecular mechanisms remain unclear. Our study may contribute to the development of novel therapeutics for myopathic diseases.
Gonadal and extragonadal pediatric germ cell tumors (GCTs) are rare neoplasms with different clinical behavior. Although surgery and cisplatin-based chemotherapy are resolutive in most cases, some patients do not respond to chemotherapy and have a worse outcome. Microsatellite instability (MSI) was correlated to resistance to chemotherapy and sensitivity to immunotherapy in different neoplasms. A series of 21 pediatric GCTs were tested by immuno-histochemistry and PCR to evaluate MSI status. Next generation sequencing was applied to further evaluate cases with discordant results between immunohistochemistry and PCR. Twenty-one cases of pediatric GCT were included in the series. The mean age ranged between 1 and 10 years. Nine cases were gonadal GCTs and the remaining 12 were extra-gonadal GCTs. By immunohistochemistry, one case showed a deficit of Mismatch repair (MMR) proteins. This case was a 1-year-old children affected by gonadal yolk sac tumor. However, all cases resulted microsatellite stable (MSS) by PCR and NGS. MSI was not detected in our series of pediatric GCTs, as well as the data present in literature about adult patients with GCTs. Molecular techniques could have a role to confirm the MSI status in case of dMMR by immunohistochemistry.
Hereditary motor and sensory neuropathy with proximal dominant involvement (HMSN-P) is an intractable neurological disease with autosomal dominant inheritance, four-limb weakness, sensory impairment, and a slowly progressive course. HMSN-P patients develop four-limb paralysis at the advanced-stage, as in amyotrophic lateral sclerosis (ALS). There is a natural 20- to 30-year course from initial painful muscle cramps and four-limb paralysis to respiratory dysfunction. A delay in the diagnosis of HMSN-P occurs due to the 20- to 30-year span from the initial symptom(s) to typical quadriplegia. Its early diagnosis is important, but the involvement of painful muscle cramps as an early symptom has not been clear. Following our earlier survey, we conducted a re-survey focusing on painful muscle cramps, assistive-device use, and hope for specific therapies in 16 Japanese patients with advanced-stage HMSN-P. Fifteen patients presented painful muscle cramps as the initial symptom, and muscle cramps in the lower abdomen including the flank were described by 10 of the patients. The presence of painful muscle cramps including those in the abdominal region may be a clue for the early diagnosis of HMSN-P. Painful abdominal cramps have not described in related diseases, e.g., ALS, spinal muscular atrophy, and Charcot-Marie-Tooth disease. Recent patient-welfare improvements and advances in assistive devices including robot-suit assistive limbs are delaying the terminal state of HMSN-P. Regarding specific therapies for HMSN-P, many patients choose both nucleic acid medicine and the application of induced pluripotent stem cells as a specific therapy for HMSN-P.
We performed a study to present a phenotypic and genotypic characterization of a patient clinically diagnosed with carbonic anhydrase II (CAII) deficiency syndrome. Medical records were reviewed, and oral examination was performed. Sanger sequencing was undertaken for molecular diagnosis. The patient presented with osteopetrosis, renal tubular acidosis, cerebral calcification, blindness, deafness, and development delay. The oral manifestations included anterior open bite, posterior crossbite, tooth eruption impairment, and hypoplastic amelogenesis imperfecta (AI). Molecular analysis revealed a CA2 homozygous deletion (c.753delG, p.Asn252Thrfs*14) and confirmed the clinical diagnosis. This study suggests that AI can be another feature of CAII deficiency syndrome. For the first time, a CA2 disease-causing variant is reported to be associated with syndromic AI.
Oncogenic PIK3CA mutation activates phosphoinositide 3-kinase (PI3K) enzyme, and PI3K-AKT signaling activation induces several growth-regulatory transcription factors. PIK3CA mutations have attracted attention as biomarker in clinical trials of various inhibitors including PI3K inhibitors. About 80% of PIK3CA mutations in human cancers are observed in 'hot spot' regions: exon 9 (E542K and E545K) and exon 20 (H1047R). There were few reports about clinical significance of PIK3CA mutations in cutaneous cell carcinoma (cSCC). Thus, we investigate the prevalence of three PIK3CA hot spot mutations in 143 cases with cSCC and evaluate the correlation between the presence of these mutations and clinical characteristics by using ddPCR. The frequency of each E542K, E545K and H1047R PIK3CA mutations was 1.4% (2/143), 2.8% (4/143), and 0.7% (1/143) respectively. No significant correlation was found between PIK3CA mutations and clinical characteristics. Although additional basic researches and clinical trials are necessary, various inhibitors may be effective therapeutics for PIK3CA mutation-positive cSCC. Our study revealed the prevalence of PIK3CA mutations in cSCC.