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Clinical Nephrology. Case Studies 2024We investigated the pathogenesis of a perihilar variant of focal segmental glomerulosclerosis detected by kidney biopsy in a 16-year-old male. The disease was refractory...
Renal and cardiac biopsy findings in an adolescent patient with the 3243A>G mitochondrial DNA mutation: Favorable renal prognosis post renal transplantation from the mother.
We investigated the pathogenesis of a perihilar variant of focal segmental glomerulosclerosis detected by kidney biopsy in a 16-year-old male. The disease was refractory to steroid therapy, and at the second kidney biopsy, abnormal mitochondrial proliferation was newly observed in the podocytes. The patient also developed late-onset hearing loss and had a family history of diabetes, and genetic testing confirmed the mitochondrial DNA mutation 3243A>G (48%). Eight months after hemodialysis was started, encephalopathy occurred presumably due to rapid dehydration. After changing dialysis into continuous ambulatory peritoneal dialysis, encephalopathy was resolved, but the patient developed myocardial hypertrophy, probably because of the myocardial overreaction to congestion. A myocardial biopsy showed mitochondrial proliferation in the myocardium. After renal transplantation from his mother with a heteroplasmy of 4%, the cardiomyopathy improved, and the renal function has remained stable for 4 years. We speculated that the abnormal mitochondrial morphology in the kidney and heart may be characteristic of mitochondrial genetic disease, and renal transplantation from the mother with a low heteroplasmy was considered desirable for mitochondrial nephropathy with poor prognosis.
PubMed: 38957708
DOI: 10.5414/CNCS111422 -
Frontiers in Immunology 2024Hemophagocytic lymphohistiocytosis (HLH) is an immune dysfunction characterized by an exaggerated and pathological inflammatory response, potentially leading to systemic... (Review)
Review
Hemophagocytic lymphohistiocytosis (HLH) is an immune dysfunction characterized by an exaggerated and pathological inflammatory response, potentially leading to systemic inflammatory reactions and multiple-organ failure, including renal involvement. HLH can be classified as primary or secondary, with primary HLH associated with genetic mutations affecting cell degranulation capacity, and secondary HLH often linked to infections, tumors, and autoimmune diseases. The pathogenesis of HLH is not fully understood, but primary HLH is typically driven by genetic defects, whereas secondary HLH involves the activation of CD8+ T cells and macrophages, leading to the release of inflammatory cytokines and systemic inflammatory response syndrome (SIRS). The clinical presentation of HLH includes non-specific manifestations, making it challenging to differentiate from severe sepsis, particularly secondary HLH due to infections. Shared features include prolonged fever, hepatosplenomegaly, hematopenia, hepatic dysfunction, hypertriglyceridemia, and hypofibrinogenemia, along with histiocytosis and hemophagocytosis. However, distinctive markers like dual hemocytopenia, hypertriglyceridemia, hypofibrinogenemia, and elevated sCD25 levels may aid in differentiating HLH from sepsis. Indeed, no singular biomarker effectively distinguishes between hemophagocytic lymphohistiocytosis and infection. However, research on combined biomarkers provides insights into the differential diagnosis. Renal impairment is frequently encountered in both HLH and sepsis. It can result from a systemic inflammatory response triggered by an influx of inflammatory mediators, from direct damage caused by these factors, or as a consequence of the primary disease process. For instance, macrophage infiltration of the kidney can lead to structural damage affecting various renal components, precipitating disease. Presently, tubular necrosis remains the predominant form of renal involvement in HLH-associated acute kidney injury (HLH-AKI). However, histopathological changes may also encompass interstitial inflammation, glomerular abnormalities, microscopic lesions, and thrombotic microangiopathy. Treatment approaches for HLH and sepsis diverge significantly. HLH is primarily managed with repeated chemotherapy to eliminate immune-activating stimuli and suppress hypercellularity. The treatment approach for sepsis primarily focuses on anti-infective therapy and intensive symptomatic supportive care. Renal function significantly influences clinical decision-making, particularly regarding the selection of chemotherapy and antibiotic dosages, which can profoundly impact patient prognosis. Conversely, renal function recovery is a complex process influenced by factors such as disease severity, timely diagnosis, and the intensity of treatment. A crucial aspect in managing HLH-AKI is the timely diagnosis, which plays a pivotal role in reversing renal impairment and creating a therapeutic window for intervention, may have opportunity to improve patient prognosis. Understanding the clinical characteristics, underlying causes, biomarkers, immunopathogenesis, and treatment options for hemophagocytic lymphohistiocytosis associated with acute kidney injury (HLH-AKI) is crucial for improving patient prognosis.
Topics: Lymphohistiocytosis, Hemophagocytic; Humans; Acute Kidney Injury; Critical Care; Biomarkers
PubMed: 38957461
DOI: 10.3389/fimmu.2024.1396124 -
Ophthalmic Genetics Jul 2024-related spliceosomeopathy is a rare autosomal recessive disorder with only 14 patients have been reported. It is characterized by retinal degeneration, short stature,...
BACKGROUND
-related spliceosomeopathy is a rare autosomal recessive disorder with only 14 patients have been reported. It is characterized by retinal degeneration, short stature, skeletal anomalies, and neurological defects. We described the clinical features of a Chinese patient with -related spliceosomeopathy and identified the pathogenic variant.
METHODS
The affected subject underwent detailed ophthalmic examinations. Systemic abnormalities were assessed, including body height, craniofacial morphology, oral cavity, hands, feet, hair and skin. Genomic DNA was isolated from peripheral blood and sequenced by next-generation sequencing. Sanger sequencing was performed for validation and segregation.
RESULTS
The patient had poor vision, nyctalopia and nystagmus from childhood. Fundoscopy revealed extensive chorioretinal atrophy with numerous scattered greyish pigmentation. Severe circular areas of macular atrophy were observed. Optical coherent tomography showed reduced retinal thickness with nearly absent ellipsoid zone and retinal pigment epithelium. In addition, craniofacial abnormalities, short statue, brachydactyly, dental anomalies, cafe-au-lait spots, scant hair, absent eyebrows and thin eyelashes were documented. Genetic analysis revealed a novel homozygous novel small deletion c.1133delG(p.G378Efs*12) in (NM_005869.2).
CONCLUSIONS
We present a patient with early-onset retinitis pigmentosa and marked syndromic features. A novel pathogenic variant was identified. Our findings broaden the clinical and mutation spectrum of -related spliceosomeopathy, and could be helpful in diagnosis of this rare disease.
PubMed: 38956876
DOI: 10.1080/13816810.2024.2368791 -
BMC Medical Genomics Jul 2024Intellectual disability (ID) is a neurodevelopmental condition affecting around 2% of children and young adults worldwide, characterized by deficits in intellectual...
BACKGROUND
Intellectual disability (ID) is a neurodevelopmental condition affecting around 2% of children and young adults worldwide, characterized by deficits in intellectual functioning and adaptive behavior. Genetic factors contribute to the development of ID phenotypes, including mutations and structural changes in chromosomes. Pathogenic variants in the HCFC1 gene cause X-linked mental retardation syndrome, also known as Siderius type X-linked mental retardation. The MN1 gene is necessary for palate development, and mutations in this gene result in a genetic condition called CEBALID syndrome.
METHODS
Exome sequencing was used to identify the disease-causing variants in two affected families, A and B, from various regions of Pakistan. Affected individuals in these two families presented ID, developmental delay, and behavioral abnormalities. The validation and co-segregation analysis of the filtered variant was carried out using Sanger sequencing.
RESULTS
In an X-linked family A, a novel hemizygous missense variant (c.5705G > A; p.Ser1902Asn) in the HCFC1 gene (NM_005334.3) was identified, while in family B exome sequencing revealed a heterozygous nonsense variant (c.3680 G > A; p. Trp1227Ter) in exon-1 of the MN1 gene (NM_032581.4). Sanger sequencing confirmed the segregation of these variants with ID in each family.
CONCLUSIONS
The investigation of two Pakistani families revealed pathogenic genetic variants in the HCFC1 and MN1 genes, which cause ID and expand the mutational spectrum of these genes.
Topics: Humans; Pakistan; Male; Pedigree; Intellectual Disability; Female; Host Cell Factor C1; Tumor Suppressor Proteins; Trans-Activators; Child; Exome Sequencing; Child, Preschool
PubMed: 38956580
DOI: 10.1186/s12920-024-01943-2 -
Scientific Reports Jul 2024Fibulin-2 is a multidomain, disulfide-rich, homodimeric protein which belongs to a broader extracellular matrix family. It plays an important role in the development of...
Fibulin-2 is a multidomain, disulfide-rich, homodimeric protein which belongs to a broader extracellular matrix family. It plays an important role in the development of elastic fiber structures. Malfunction of fibulin due to mutation or poor expression can result in a variety of diseases including synpolydactyly, limb abnormalities, eye disorders leading to blindness, cardiovascular diseases and cancer. Traditionally, fibulins have either been produced in mammalian cell systems or were isolated from the extracellular matrix, a procedure that results in poor availability for structural and functional studies. Here, we produced seven fibulin-2 constructs covering 62% of the mature protein (749 out of 1195 residues) using a prokaryotic expression system. Biophysical studies confirm that the purified constructs are folded and that the presence of disulfide bonds within the constructs makes them extremely thermostable. In addition, we solved the first crystal structure for any fibulin isoform, a structure corresponding to the previously suggested three motifs related to anaphylatoxin. The structure reveals that the three anaphylatoxins moieties form a single-domain structure.
Topics: Humans; Calcium-Binding Proteins; Extracellular Matrix Proteins; Crystallography, X-Ray; Models, Molecular; Protein Conformation; Recombinant Proteins; Protein Stability; Protein Domains
PubMed: 38956220
DOI: 10.1038/s41598-024-64931-7 -
Scientific Reports Jul 2024KCNQ4 is a voltage-gated K channel was reported to distribute over the basolateral surface of type 1 vestibular hair cell and/or inner surface of calyx and heminode of...
KCNQ4 is a voltage-gated K channel was reported to distribute over the basolateral surface of type 1 vestibular hair cell and/or inner surface of calyx and heminode of the vestibular nerve connected to the type 1 vestibular hair cells of the inner ear. However, the precise localization of KCNQ4 is still controversial and little is known about the vestibular phenotypes caused by KCNQ4 dysfunction or the specific role of KCNQ4 in the vestibular organs. To investigate the role of KCNQ4 in the vestibular organ, 6-g hypergravity stimulation for 24 h, which represents excessive mechanical stimulation of the sensory epithelium, was applied to p.W277S Kcnq4 transgenic mice. KCNQ4 was detected on the inner surface of calyx of the vestibular afferent in transmission electron microscope images with immunogold labelling. Vestibular function decrease was more severe in the Kcnq4 mice than in the Kcnq4 and Kcnq4 mice after the stimulation. The vestibular function loss was resulted from the loss of type 1 vestibular hair cells, which was possibly caused by increased depolarization duration. Retigabine, a KCNQ activator, prevented hypergravity-induced vestibular dysfunction and hair cell loss. Patients with KCNQ4 mutations also showed abnormal clinical vestibular function tests. These findings suggest that KCNQ4 plays an essential role in calyx and afferent of type 1 vestibular hair cell preserving vestibular function against excessive mechanical stimulation.
Topics: Animals; KCNQ Potassium Channels; Hair Cells, Vestibular; Mice; Mice, Transgenic; Phenylenediamines; Carbamates; Vestibule, Labyrinth
PubMed: 38956136
DOI: 10.1038/s41598-024-66115-9 -
Journal of Neurology Jul 2024Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common genetically inherited myopathies in adults. It is characterized by incomplete penetrance and... (Review)
Review
Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common genetically inherited myopathies in adults. It is characterized by incomplete penetrance and variable expressivity. Typically, FSHD patients display asymmetric weakness of facial, scapular, and humeral muscles that may progress to other muscle groups, particularly the abdominal and lower limb muscles. Early-onset patients display more severe muscle weakness and atrophy, resulting in a higher frequency of associated skeletal abnormalities. In these patients, multisystem involvement, including respiratory, ocular, and auditory, is more frequent and severe and may include the central nervous system. Adult-onset FSHD patients may also display some degree of multisystem involvement which mainly remains subclinical. In 95% of cases, FSHD patients carry a pathogenic contraction of the D4Z4 repeat units (RUs) in the subtelomeric region of chromosome 4 (4q35), which leads to the expression of DUX4 retrogene, toxic for muscles (FSHD1). Five percent of patients display the same clinical phenotype in association with a mutation in the SMCHD1 gene located in chromosome 18, inducing epigenetic modifications of the 4q D4Z4 repeated region and expression of DUX4 retrogene. This review highlights the complexities and challenges of diagnosing and managing FSHD, underscoring the importance of standardized approaches for optimal patient outcomes. It emphasizes the critical role of multidisciplinary care in addressing the diverse manifestations of FSHD across different age groups, from skeletal abnormalities in early-onset cases to the often-subclinical multisystem involvement in adults. With no current cure, the focus on alleviating symptoms and slowing disease progression through coordinated care is paramount.
PubMed: 38955828
DOI: 10.1007/s00415-024-12538-3 -
Zhonghua Er Ke Za Zhi = Chinese Journal... Jul 2024
Review
Topics: Nephritis, Hereditary; Genetic Therapy; Humans; Collagen Type IV; Animals; Disease Models, Animal; Mutation; Genetic Vectors; Gene Transfer Techniques; Mice; Basement Membrane
PubMed: 38955691
DOI: 10.3760/cma.j.cn112140-20240222-00118 -
Zhonghua Er Ke Za Zhi = Chinese Journal... Jul 2024
Topics: Humans; Gynecomastia; Male; Child; Aromatase; Anastrozole; Exome Sequencing; Nitriles; Triazoles; Phenotype; Mutation; Breast; Pedigree
PubMed: 38955690
DOI: 10.3760/cma.j.cn112140-20231123-00387 -
BMJ Case Reports Jul 2024Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare autosomal recessive disease caused by mutation in proteoglycan 4 (PRG4) gene on chromosome...
Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare autosomal recessive disease caused by mutation in proteoglycan 4 (PRG4) gene on chromosome 1q25-q31. We faced a dilemma and delay in diagnosis in two sisters. The elder sister had pericardial effusion with constrictive pericarditis, underwent pericardiectomy and received empirical treatment for suspected tuberculosis. After 2 years, she developed bilateral knee swelling with restriction of movement. At the same time, her younger sister also presented with bilateral knee swelling which aroused the suspicion of genetic disease. The whole-genome sequencing revealed homozygous PRG4 mutation suggestive of CACP syndrome.
Topics: Humans; Female; Coxa Vara; Proteoglycans; Hand Deformities, Congenital; Arthropathy, Neurogenic; Pericardial Effusion; Upper Extremity Deformities, Congenital; Pericarditis, Constrictive; Lower Extremity Deformities, Congenital; Pericardiectomy; Mutation; Diagnosis, Differential; Synovitis
PubMed: 38955384
DOI: 10.1136/bcr-2024-260146