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Summary Shwachman–Diamond syndrome represents a clinically and genetically heterogeneous disorder. We report on an infant with a very severe, fatal clinical course caused by biallelic EFL1 variants: c.89A>G, p.(His30Arg), and c.2599A>G, p.(Asn867Asp). Functional analysis of patient‐derived B‐lymphoblastoid and SV40‐transformed fibroblast cell lines suggests that the compound heterozygous EFL1 variants impaired mature ribosome formation leading to compromised protein synthesis, ultimately resulting in a severe form of Shwachman–Diamond syndrome. [ABSTRACT FROM AUTHOR]

Shwachman–Diamond syndrome (SDS) is an inherited bone marrow failure disorder that often presents at infancy. Progress has been made in revealing causal mutated genes (SBDS and others), ribosome defects, and hematopoietic aberrations in SDS. However, the mechanism underlying the hematopoietic failure remained unknown, and treatment options are limited. Herein, we investigated the onset of SDS embryonic hematopoietic impairments. We generated SDS and control human‐derived induced pluripotent stem cells (iPSCs). SDS iPSCs recapitulated the SDS hematological phenotype. Detailed stepwise evaluation of definitive hematopoiesis revealed defects that started at the early emerging hematopoietic progenitor (EHP) stage after mesoderm and hemogenic endothelium were normally induced. Hematopoietic potential of EHPs was markedly reduced, and the introduction of SBDS in SDS iPSCs improved colony formation. Transcriptome analysis revealed reduced expression of ribosome and oxidative phosphorylation‐related genes in undifferentiated and differentiated iPSCs. However, certain pathways (e.g., DNA replication) and genes (e.g., CHCHD2) were exclusively or more severely dysregulated in EHPs compared with earlier and later stages. To our knowledge, this study offers for the first time an insight into the embryonic onset of human hematopoietic defects in an inherited bone marrow failure syndrome and reveals cellular and molecular aberrations at critical stages of hematopoietic development toward EHPs. [ABSTRACT FROM AUTHOR]

Background: Congenital neutropenias are characterized by severe infections and a high risk of myeloid transformation; the causative genes vary across ethnicities. The Israeli population is characterized by an ethnically diverse population with a high rate of consanguinity. Objective: To evaluate the clinical and genetic spectrum of congenital neutropenias in Israel. Methods: We included individuals with congenital neutropenias listed in the Israeli Inherited Bone Marrow Failure Registry. Sanger sequencing was performed for ELANE or G6PC3, and patients with wild‐type ELANE/G6PC3 were referred for next‐generation sequencing. Results: Sixty‐five patients with neutropenia were included. Of 51 patients with severe congenital neutropenia, 34 were genetically diagnosed, most commonly with variants in ELANE (15 patients). Nine patients had biallelic variants in G6PC3, all of consanguineous Muslim Arab origin. Other genes involved were SRP54, JAGN1, TAZ, and SLC37A4. Seven patients had cyclic neutropenia, all with pathogenic variants in ELANE, and seven had Shwachman–Diamond syndrome caused by biallelic SBDS variants. Eight patients (12%) developed myeloid transformation, including six patients with an unknown underlying genetic cause. Nineteen (29%) patients underwent hematopoietic stem cell transplantation, mostly due to insufficient response to treatment with granulocyte‐colony stimulating factor or due to myeloid transformation. Conclusions: The genetic spectrum of congenital neutropenias in Israel is characterized by a high prevalence of G6PC3 variants and an absence of HAX1 mutations. Similar to other registries, for 26% of the patients, a molecular diagnosis was not achieved. However, myeloid transformation was common in this group, emphasizing the need for close follow‐up. [ABSTRACT FROM AUTHOR]

Shwachman Diamond Syndrome (SDS) is a multi-system disease characterized by exocrine pancreatic insufficiency with malabsorption, infantile neutropenia and aplastic anemia. Life-threatening complications include progression to acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS), critical deep-tissue infections and asphyxiating thoracic dystrophy. In most patients, SDS results from biallelic pathogenic variants in the SBDS gene, different combinations of which contribute to heterogenous clinical presentations. Null variants are not well tolerated, supporting the theory that the loss of SBDS expression is likely lethal in both mice and humans. A novel complex genotype (SBDS:c.[242C>G;258+2T>C];[460-1G>A]/WFS1:c.[2327A>T];[1371G>T]) was detected in a family with recurrent neonatal deaths. A female neonate died three hours after birth with hemolytic anemia, and a male neonate with severe anemia, thrombocytopenia and neutropenia succumbed on day 40 after Staphylococcus epidermidis infection. A subsequent review of the literature focused on fatal complications, complex SBDS genotypes and/or unusual clinical presentations and disclosed rare cases, of which some had unexpected combinations of genetic and clinical findings. The impact of pathogenic variants and associated phenotypes is discussed in the context of data sharing towards expanding scientific expert networks, consolidating knowledge and advancing an understanding of novel underlying genotypes and complex phenotypes, facilitating informed clinical decisions and disease management. [ABSTRACT FROM AUTHOR]

Objective: To discuss the clinical characteristics, diagnosis, and treatment of ShwachmanDiamond syndrome (SDS), and to enhance the clinicians' awareness of the disease. Methods: The clinical materials of one patient diagnosed with SDS, primarily presented with neutropenia and elevated transaminase levels, confirmed by genetic testing were retrospectively analyzed. The clinical manifestations, genetic features, diagnosis, and treatment methods of SDS were analyzed complemented with the relevant literatures. Results: This patient was a male child, aged 27 months. His initial clinical presentations were neutropenia and elevated transaminase levels. The patient had previously experienced diarrhea when the patient was 3 months old, which improved after treated with oral pancreatic enzyme dispersion. Over the past six months, the patient had recurrent respiratory infections. Upon admission, the examination results showed there was dental enamel hypoplasia, and the imaging results showed the abnormal bone density in the long bones of the limbs. The genetic sequencing results showed a homozygous mutation in the Shwachman-Bodian-Diamond syndrome (SBDS) gene (c. 258+2T>C). During hospitalization, the patient received the hepatoprotective care and granulocyte augmentation supportive treatment, leading to an improvement in his condition, and the patient was discharged. During a one-year follow-up, the patient's condition was stable. Conclusion: The typical presentation of the SDS patient includes diarrhea, liver function abnormalities, hematologic abnormalities, and skeletal anomalies, particularly neutropenia; there may also be developmental delays and involvement of the heart, liver, central nervous system, skeleton, and immune system. The genetic testing of suspected children is crucial, and it can aid in the early diagnosis and treatment of SDS patients. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we drew up the growth charts of Italian patients with Shwachman–Diamond syndrome (SDS) at ages 0 to 18 years. We found that the 50th and 3rd percentiles of weight and height of the pediatric general population correspond to the 97th and 50th percentiles of patients with SDS, respectively. The median age at menarche in females with SDS was comparable with that of the general population. The percentage increment in weight of subjects aged 14–18 years was higher in patients with SDS than in the general population. This study provides insight into the potential usefulness of SDS-specific growth chart data as a resource for clinicians working with patients with SDS. Shwachman–Diamond syndrome (SDS) is one of the most common inherited bone marrow failure syndromes. SDS is characterized by hypocellular bone marrow, with a severe impairment of the myeloid lineage, resulting in neutropenia, thrombocytopenia, and, more rarely, anemia. Almost 15% of patients with SDS develop myelodysplastic syndrome or acute myeloid leukemia as early as childhood or young adulthood. Exocrine pancreatic insufficiency is another common feature of SDS. Almost all patients with SDS show failure to thrive, which is associated with skeletal abnormalities due to defective ossification. Considering these observations, it remains unfeasible to use the common growth charts already available for the general population. To address this issue, we report how we drew up growth charts of patients with SDS aged 0 to 18 years. We analyzed height, weight, and body max index (BMI) in 121 Italian patients with SDS. Results indicated that the 50th and 3rd percentiles of weight and height of the pediatric general population correspond to the 97th and 50th percentiles of patients with SDS aged 0–18 years, respectively. In addition, the percentage increment in weight of subjects aged 14–18 years was higher in patients with SDS than in the general population. SDS-specific growth charts, such as those described here, afford a new tool, which is potentially useful for both clinical and research purposes in SDS. [ABSTRACT FROM AUTHOR]

Introduction: The inherited bone marrow failure syndromes (IBMFSs) are a group of rare disorders characterized by bone marrow failure (BMF), physical abnormalities, and an increased risk of neoplasia. The National Institute of Pediatrics (INP) is a major medical institution in Mexico, where patients with BMF receive a complete approach that includes paraclinical tests. Readily recognizable features, such as the hematological and distinctive physical phenotypes, identified by clinical dysmorphologists, remain crucial for the diagnosis and management of these patients, particularly in circumstances where next-generation sequencing (NGS) is not easily available. Here, we describe a group of Mexican patients with a high clinical suspicion of an IBMFS. Methods: We performed a systematic retrospective analysis of the medical records of patients who had a high IBMFS suspicion at our institution from January 2018 to July 2021. An initial assessment included first ruling out acquired causes of BMF by the Hematology Department and referral of the patient to the Department of Human Genetics for physical examination to search for specific phenotypes suggesting an IBMFS. Patients with high suspicion of having an IBMFS were classified into two main groups: 1) specific IBMFS, including dyskeratosis congenita (DC), Diamond-Blackfan anemia (DBA), Shwachman-Diamond syndrome (SDS), thrombocytopenia with absent radii (TAR), and severe congenital neutropenia (SCN); 2) undefined IBMFS (UI). Results: We established a high suspicion of having an IBMFS in 48 patients. At initial evaluation, the most common hematologic features were bicytopenia (20%) and aplastic anemia (16%); three patients received hematopoietic stem cell transplantation. Among patients with a suspicion of an IBMFS, the most common physical abnormality was minor craniofacial features in 83% of patients and neurodevelopmental disorders in 52%. The specific suspicions that we built were DBA (31%), SDS (18%), DC (14%), TAR (4%), and SCN (4%), whereas 27% of cases remained as undefined IBMFS. SDS, TAR, and SCN were more commonly suspected at an earlier age (<1 year), followed by DBA (2 years) and DC (5 years). Conclusions: Thorough examination of reported clinical data allowed us to highly suspect a specific IBMFS in approximately 70% of patients; however, an important number of patients remained with suspicion of an undefined IBMFS. Implementation of NGS and telomere length measurement are forthcoming measures to improve IBMFS diagnosis in Mexico. [ABSTRACT FROM AUTHOR]

Summary: Shwachman–Diamond syndrome (SDS) is characterized by neutropenia, exocrine pancreatic insufficiency and skeletal abnormalities. SDS bone marrow haematopoietic progenitors show increased apoptosis and impairment in granulocytic differentiation. Loss of Shwachman–Bodian–Diamond syndrome (SBDS) expression results in reduced eukaryotic 80S ribosome maturation. Biallelic mutations in the SBDS gene are found in ~90% of SDS patients, ~55% of whom carry the c.183‐184TA>CT nonsense mutation. Several translational readthrough‐inducing drugs aimed at suppressing nonsense mutations have been developed. One of these, ataluren, has received approval in Europe for the treatment of Duchenne muscular dystrophy. We previously showed that ataluren can restore full‐length SBDS protein synthesis in SDS‐derived bone marrow cells. Here, we extend our preclinical study to assess the functional restoration of SBDS capabilities in vitro and ex vivo. Ataluren improved 80S ribosome assembly and total protein synthesis in SDS‐derived cells, restored myelopoiesis in myeloid progenitors, improved neutrophil chemotaxis in vitro and reduced neutrophil dysplastic markers ex vivo. Ataluren also restored full‐length SBDS synthesis in primary osteoblasts, suggesting that its beneficial role may go beyond the myeloid compartment. Altogether, our results strengthened the rationale for a Phase I/II clinical trial of ataluren in SDS patients who harbour the nonsense mutation. [ABSTRACT FROM AUTHOR]

Background: Shwachman-Diamond syndrome (SDS) is an autosomal recessive disease which results in inherited bone marrow failure (IBMF) and is characterized by exocrine pancreatic dysfunction and diverse clinical phenotypes. In the present study, we reviewed the internationally published reports on SDS patients, in order to summarize the clinical features, epidemiology, and treatment of SDS. Methods: We searched the WangFang and China National Knowledge Infrastructure databases with the keywords "Shwachman-Diamond syndrome," "SDS," "SBDS gene" and "inherited bone marrow failure" for relevant articles published from January 2002 to October 2022. In addition, studies published from January 2002 to October 2022 were searched from the Web of Science, PubMed, and MEDLINE databases, using "Shwachman-diamond syndrome" as the keyword. Finally, one child with SDS treated in Tongji Hospital was also included. Results: The clinical features of 156 patients with SDS were summarized. The three major clinical features of SDS were found to be peripheral blood cytopenia (96.8%), exocrine pancreatic dysfunction (83.3%), and failure to thrive (83.3%). The detection rate of SDS mutations was 94.6% (125/132). Mutations in SBDS, DNAJC21, SRP54, ELF6, and ELF1 have been reported. The male-to-female ratio was approximately 1.3/1. The median age of onset was 0.16 years, but the diagnostic age lagged by a median age of 1.3 years. Conclusions: Pancreatic exocrine insufficiency and growth failure were common initial symptoms. SDS onset occurred early in childhood, and individual differences were obvious. Comprehensive collection and analysis of case-related data can help clinicians understand the clinical characteristics of SDS, which may improve early diagnosis and promote effective clinical intervention. [ABSTRACT FROM AUTHOR]

Abstract Background Shwachman-Diamond syndrome (SDS) is an autosomal recessive disease which results in inherited bone marrow failure (IBMF) and is characterized by exocrine pancreatic dysfunction and diverse clinical phenotypes. In the present study, we reviewed the internationally published reports on SDS patients, in order to summarize the clinical features, epidemiology, and treatment of SDS. Methods We searched the WangFang and China National Knowledge Infrastructure databases with the keywords “Shwachman-Diamond syndrome,” “SDS,” “SBDS gene” and “inherited bone marrow failure” for relevant articles published from January 2002 to October 2022. In addition, studies published from January 2002 to October 2022 were searched from the Web of Science, PubMed, and MEDLINE databases, using “Shwachman-diamond syndrome” as the keyword. Finally, one child with SDS treated in Tongji Hospital was also included. Results The clinical features of 156 patients with SDS were summarized. The three major clinical features of SDS were found to be peripheral blood cytopenia (96.8%), exocrine pancreatic dysfunction (83.3%), and failure to thrive (83.3%). The detection rate of SDS mutations was 94.6% (125/132). Mutations in SBDS, DNAJC21, SRP54, ELF6, and ELF1 have been reported. The male-to-female ratio was approximately 1.3/1. The median age of onset was 0.16 years, but the diagnostic age lagged by a median age of 1.3 years. Conclusions Pancreatic exocrine insufficiency and growth failure were common initial symptoms. SDS onset occurred early in childhood, and individual differences were obvious. Comprehensive collection and analysis of case-related data can help clinicians understand the clinical characteristics of SDS, which may improve early diagnosis and promote effective clinical intervention.

Abstract Background Shwachman-Diamond syndrome (SDS) is a rare congenital disorder caused by mutations in the SBDS gene and characterized by exocrine pancreatic deficiency, hematologic dysfunction, and skeletal growth failure. Although the hematologic features and characteristics of the somatic disorders commonly associated with SDS are well known, emerging data from case reports and patient registries suggest that SDS may also be associated with an increased risk of diabetes mellitus. However, currently available data on SDS-associated diabetes are limited and do not allow conclusions regarding prevalence and incidence rates, clinical course, and outcomes. Case presentation Here we report the case of a 5-year-old girl with SDS who underwent bone marrow transplantation at the age of 3 months and developed autoantibody-positive type 1 diabetes mellitus at the age of 1.8 years. The manifestation and course of diabetes development were mild, complicated by concurrent spontaneous episodes of hypoglycemia even before the onset of antidiabetic treatment. Currently, adequate metabolic control can be achieved by dietary intervention. Conclusions Considering that the SBDS protein regulates mitosis and ribosomal biosynthesis and that its suppression may cause immunologic instability and chronic inflammation, this case provides insight into the phenotype of rare Shwachman-Diamond syndrome-associated diabetes mellitus, which may be characterized by significant age-dependent differences in clinical course.

Introduction: The inherited bone marrow failure syndromes (IBMFSs) are a group of rare disorders characterized by bone marrow failure (BMF), physical abnormalities, and an increased risk of neoplasia. The National Institute of Pediatrics (INP) is a major medical institution in Mexico, where patients with BMF receive a complete approach that includes paraclinical tests. Readily recognizable features, such as the hematological and distinctive physical phenotypes, identified by clinical dysmorphologists, remain crucial for the diagnosis and management of these patients, particularly in circumstances where next-generation sequencing (NGS) is not easily available. Here, we describe a group of Mexican patients with a high clinical suspicion of an IBMFS.Methods: We performed a systematic retrospective analysis of the medical records of patients who had a high IBMFS suspicion at our institution from January 2018 to July 2021. An initial assessment included first ruling out acquired causes of BMF by the Hematology Department and referral of the patient to the Department of Human Genetics for physical examination to search for specific phenotypes suggesting an IBMFS. Patients with high suspicion of having an IBMFS were classified into two main groups: 1) specific IBMFS, including dyskeratosis congenita (DC), Diamond–Blackfan anemia (DBA), Shwachman–Diamond syndrome (SDS), thrombocytopenia with absent radii (TAR), and severe congenital neutropenia (SCN); 2) undefined IBMFS (UI).Results: We established a high suspicion of having an IBMFS in 48 patients. At initial evaluation, the most common hematologic features were bicytopenia (20%) and aplastic anemia (16%); three patients received hematopoietic stem cell transplantation. Among patients with a suspicion of an IBMFS, the most common physical abnormality was minor craniofacial features in 83% of patients and neurodevelopmental disorders in 52%. The specific suspicions that we built were DBA (31%), SDS (18%), DC (14%), TAR (4%), and SCN (4%), whereas 27% of cases remained as undefined IBMFS. SDS, TAR, and SCN were more commonly suspected at an earlier age (

Background: Shwachman-Diamond syndrome (SDS) is a rare congenital disorder caused by mutations in the SBDS gene and characterized by exocrine pancreatic deficiency, hematologic dysfunction, and skeletal growth failure. Although the hematologic features and characteristics of the somatic disorders commonly associated with SDS are well known, emerging data from case reports and patient registries suggest that SDS may also be associated with an increased risk of diabetes mellitus. However, currently available data on SDS-associated diabetes are limited and do not allow conclusions regarding prevalence and incidence rates, clinical course, and outcomes. Case presentation: Here we report the case of a 5-year-old girl with SDS who underwent bone marrow transplantation at the age of 3 months and developed autoantibody-positive type 1 diabetes mellitus at the age of 1.8 years. The manifestation and course of diabetes development were mild, complicated by concurrent spontaneous episodes of hypoglycemia even before the onset of antidiabetic treatment. Currently, adequate metabolic control can be achieved by dietary intervention. Conclusions: Considering that the SBDS protein regulates mitosis and ribosomal biosynthesis and that its suppression may cause immunologic instability and chronic inflammation, this case provides insight into the phenotype of rare Shwachman-Diamond syndrome-associated diabetes mellitus, which may be characterized by significant age-dependent differences in clinical course. [ABSTRACT FROM AUTHOR]

Inherited bone marrow failure syndromes (IBMFSs) include Fanconi anemia, Diamond–Blackfan anemia, Shwachman–Diamond syndrome, dyskeratosis congenita, severe congenital neutropenia, and other rare entities such as GATA2 deficiency and SAMD9/9L mutations. The IBMFS monogenic disorders were first recognized by their phenotype. Exome sequencing has validated their classification, with clusters of gene mutations affecting DNA damage response (Fanconi anemia), ribosome structure (Diamond–Blackfan anemia), ribosome assembly (Shwachman–Diamond syndrome), or telomere maintenance/stability (dyskeratosis congenita). The pathogenetic mechanisms of IBMFSs remain to be characterized fully, but an overarching hypothesis states that different stresses elicit TP53-dependent growth arrest and apoptosis of hematopoietic stem, progenitor, and precursor cells. Here, we review the IBMFSs and propose a role for pro-inflammatory cytokines, such as TGF-β, IL-1β, and IFN-α, in mediating the cytopenias. We suggest a pathogenic role for cytokines in the transformation to myeloid neoplasia and hypothesize a role for anti-inflammatory therapies. [ABSTRACT FROM AUTHOR]

Pediatric patients with exocrine pancreatic insufficiency (EPI) have symptoms that include abdominal pain, weight loss or poor weight gain, malnutrition, and steatorrhea. This condition can be present at birth or develop during childhood for certain genetic disorders. Cystic fibrosis (CF) is the most prevalent disorder in which patients are screened for EPI; other disorders also are associated with pancreatic dysfunction, such as hereditary pancreatitis, Pearson syndrome, and Shwachman-Diamond syndrome. Understanding the clinical presentation and proposed pathophysiology of the pancreatic dysfunction of these disorders aids in diagnosis and treatment. Testing pancreatic function is challenging. Directly testing aspirates produced from the pancreas after stimulation is considered the gold standard, but the procedures are not standardized or widely available. Instead, indirect tests are often used in diagnosis and monitoring. Although indirect tests are more widely available and easier to perform, they have inherent limitations due to a lack of sensitivity and/or specificity for EPI. [ABSTRACT FROM AUTHOR]

To understand the mechanisms that mediate germline genetic leukemia predisposition, we studied the inherited ribosomopathy Shwachman-Diamond syndrome (SDS), a bone marrow failure disorder with high risk of myeloid malignancies at an early age. To define the mechanistic basis of clonal hematopoiesis in SDS, we investigate somatic mutations acquired by patients with SDS followed longitudinally. Here we report that multiple independent somatic hematopoietic clones arise early in life, most commonly harboring heterozygous mutations in EIF6 or TP53. We show that germline SBDS deficiency establishes a fitness constraint that drives selection of somatic clones via two distinct mechanisms with different clinical consequences. EIF6 inactivation mediates a compensatory pathway with limited leukemic potential by ameliorating the underlying SDS ribosome defect and enhancing clone fitness. TP53 mutations define a maladaptive pathway with enhanced leukemic potential by inactivating tumor suppressor checkpoints without correcting the ribosome defect. Subsequent development of leukemia was associated with acquisition of biallelic TP53 alterations. These results mechanistically link leukemia predisposition to germline genetic constraints on cellular fitness, and provide a rational framework for clinical surveillance strategies.

• Monitoring of human SBDS activity using noncanonical amino acid labeling. • Select domains of SBDS can be site-specifically labeled. • Fluorescence anisotropy captures interactions between labeled SBDS and 60S subunit. The Shwachman-Diamond syndrome (SDS) is a rare inherited ribosomopathy that is predominantly caused by mutations in the Shwachman-Bodian-Diamond Syndrome gene (SBDS). SBDS is a ribosomal maturation factor that is essential for the release of eukaryotic translation initiation factor 6 (eIF6) from 60S ribosomal subunits during the late stages of 60S maturation. Release of eIF6 is critical to permit inter-subunit interactions between the 60S and 40S subunits and to form translationally competent 80S monosomes. SBDS has three key domains that are highly flexible and adopt varied conformations in solution. To better understand the domain dynamics of SBDS upon binding to 60S and to assess the effects of SDS-disease specific mutations, we aimed to site-specifically label individual domains of SBDS. Here we detail the generation of a fluorescently labeled SBDS to monitor the dynamics of select domains upon binding to 60S. We describe the incorporation of 4-azido-l-phenylalanine (4AZP), a noncanonical amino acid in human SBDS. Site-specific labeling of SBDS using fluorophore and assessment of 60S binding activity are also described. Such labeling approaches to capture the interactions of individual domains of SBDS with 60S are also applicable to study the dynamics of other multi-domain proteins that interact with the ribosomal subunits. [ABSTRACT FROM AUTHOR]

Shwachman–Diamond syndrome (SDS) represents one of the most common inherited bone marrow failure syndromes and is mainly caused by SBDS gene mutations. Only supportive treatments are available, with hematopoietic cell transplantation required when marrow failure occurs. Among all causative mutations, the SBDS c.258+2T>C variant at the 5′ splice site (ss) of exon 2 is one of the most frequent. Here, we investigated the molecular mechanisms underlying aberrant SBDS splicing and showed that SBDS exon 2 is dense in splicing regulatory elements and cryptic splice sites, complicating proper 5′ss selection. Studies ex vivo and in vitro demonstrated that the mutation alters splicing, but it is also compatible with tiny amounts of correct transcripts, which would explain the survival of SDS patients. Moreover, for the first time for SDS, we explored a panel of correction approaches at the RNA and DNA levels and provided experimental evidence that the mutation effect can be partially counteracted by engineered U1snRNA, trans-splicing, and base/prime editors, ultimately leading to correctly spliced transcripts (from barely detectable to 2.5–5.5%). Among them, we propose DNA editors that, by stably reverting the mutation and potentially conferring positive selection to bone-marrow cells, could lead to the development of an innovative SDS therapy. [ABSTRACT FROM AUTHOR]

Shwachman-Diamond syndrome is a multisystem autosomal recessive disorder characterized by pancreatic and bone marrow abnormalities with frequent liver involvement.Patients with SDS display aminotransaminase elevation and hepatomegaly in their early childhood. For most of the patients, the syptoms tend to improve as they grow. However, a number of the children with progress into cirrhosis even liver failure, and the prognosis is poor.This paper summarizes advances in the epidemiology, pathogenesis, clinical manifestations, and diagnosis and treatment of hepatopathy in Shwachman-Diamond syndrome.

We present the case of a 53-yr-old woman with an inherited bone marrow failure coexisting with uncommon extrahematological symptoms, such as cirrhosis and skin abnormalities. Whole-exome sequencing revealed a diagnosis of Shwachman-Diamond syndrome (SDS) with an atypical presentation. Unexpected was the age of disease expression, normally around the pediatric age, with a predominantly median survival age of 36 yr. To our knowledge, she was the first adult patient with a molecular diagnosis of Shwachman-Diamond in Uruguay. The patient was referred to our service when she was 43-yr-old with a history of bone marrow failure with anemia and thrombocytopenia. All secondary causes of pancytopenia were excluded. Bone marrow aspirate and biopsy specimens were hypocellular for the patient's age. Numerous dysplastic features were observed in the three lineages. She had a normal karyotype and normal chromosomal fragility. A diagnosis of low-risk hypoplastic MDS was made. Dermatological examination revealed reticulate skin pigmentation with hypopigmented macules involving the face, neck, and extremities; nail dystrophy; premature graying; and thin hair. Extrahematological manifestations were present (e.g., learning difficulties, short stature). Last, she was diagnosed with cryptogenic liver cirrhosis CHILD C. This rules out all other possible causes of chronic liver disease. This clinical presentation initially oriented the diagnosis toward telomeropathy, so we did a telomeropathy NGS panel that came up negative. Finally, we did an exome sequencing that confirmed the diagnosis of SDS. Using whole-exome sequencing, we were able to find two compound heterozygous mutations in the SBDS gene that were responsible for the phenotype of a patient that was undiagnosed for 10 years. An earlier genetic diagnosis could have influenced our patient's outcome. [ABSTRACT FROM AUTHOR]

A case study of 16-day-old male born at 36w4d via repeat C-section to a 38-year-old G9P3 mother is presented. Topics include examines prenatal history was significant for polyhydramnios, maternal UDS positive for marijuana use and concern for cigarette smoking; and considered mother has a history of several spontaneous abortions and two ectopic pregnancies.

BackgroundShwachman-Diamond syndrome (SDS) is a rare autosomal recessive genetic disease that has complex and various clinical presentations. With the increase in application and clinical sensitivity of genome sequencing, the diagnoses of SDS in children and adults using genome sequencing have increased significantly, but most Chinese SDS patients have not received systematic and standardized treatment after diagnosis.ObjectiveTo analyze the clinical characteristics, diagnosis and treatment of three children with SDS, expecting to improve clinicians' recognition of this disease, reduce the possibilities of missed diagnosis and misdiagnosis, and standardize the treatment of diagnosed children.MethodsData of three children with SDS were collected from Department of Pediatrics, Peking University First Hospital from October 2018 to October 2020, including clinical manifestations, laboratory examination, gene analysis, treatment and follow-up, and were analyzed. In combination with the review of other relevant literature, the diagnosis and treatment of pediatric cases of SDS were summarized.ResultsAmong the three cases encountered and treated by us, two were female and one was male. All of them had recurrent infection, fatty diarrhea, short stature and malnutrition. Case 2 also had syndactyly. Auxiliary tests suggested that all these cases had neutropenia and abnormal liver function. Besides that, case 1 also had severe anemia, and case 2 had thrombocytopenia. Two compound heterozygous mutations of SBDS gene, that is, c.258 + 2T>C and c.184A>T, were found in all three cases. For treatment, all three patients were given pancreatic enzyme replacement therapy, nutritional support, and hepatoprotective treatment. The anemia of case 1, which was dependent on suspended red blood cell transfusion, was obviously improved after low-dose prednisone treatment.ConclusionSDS is a disease with multiple systems involved. Gene detection is helpful to the early diagnosis of SDS. Comprehensive, multidisciplinary treatment is needed. Hematopoietic stem cell transplantation with reduced dose pretreatment can improve some clinical manifestations, but the transplantation indications should be strictly controlled. Low dose and short course of glucocorticoid could be used to reduce the dependence on blood products for those with low erythropoiesis and no hematopoietic stem cell transplantation conditions.

Inherited bone marrow failure syndromes (IBMFSs) include Fanconi anemia, Diamond–Blackfan anemia, Shwachman–Diamond syndrome, dyskeratosis congenita, severe congenital neutropenia, and other rare entities such as GATA2 deficiency and SAMD9/9L mutations. The IBMFS monogenic disorders were first recognized by their phenotype. Exome sequencing has validated their classification, with clusters of gene mutations affecting DNA damage response (Fanconi anemia), ribosome structure (Diamond–Blackfan anemia), ribosome assembly (Shwachman–Diamond syndrome), or telomere maintenance/stability (dyskeratosis congenita). The pathogenetic mechanisms of IBMFSs remain to be characterized fully, but an overarching hypothesis states that different stresses elicit TP53-dependent growth arrest and apoptosis of hematopoietic stem, progenitor, and precursor cells. Here, we review the IBMFSs and propose a role for pro-inflammatory cytokines, such as TGF-β, IL-1β, and IFN-α, in mediating the cytopenias. We suggest a pathogenic role for cytokines in the transformation to myeloid neoplasia and hypothesize a role for anti-inflammatory therapies.

Recent evidence has implicated EFL1 in a phenotype overlapping Shwachman-Diamond syndrome (SDS), with the functional interplay between EFL1 and the previously known causative gene SBDS accounting for the similarity in clinical features. Relatively little is known about the phenotypes associated with pathogenic variants in the EFL1 gene, but the initial indication was that phenotypes may be more severe, when compared with SDS. We report a pediatric patient who presented with a metaphyseal dysplasia and was found to have biallelic variants in EFL1 on reanalysis of trio whole-exome sequencing data. The variant had not been initially reported because of the research laboratorys focus on de novo variants. Subsequent phenotyping revealed variability in her manifestations. Although her metaphyseal abnormalities were more severe than in the original reported cohort with EFL1 variants, the bone marrow abnormalities were generally mild, and there was equivocal evidence for pancreatic insufficiency. Despite the limited number of reported patients, variants in EFL1 appear to cause a broader spectrum of symptoms that overlap with those seen in SDS. Our report adds to the evidence of EFL1 being associated with an SDS-like phenotype and provides information adding to our understanding of the phenotypic variability of this disorder. Our report also highlights the value of exome data reanalysis when a diagnosis is not initially apparent.

Abstract Background An isochromosome of the long arm of chromosome 7, i(7)(q10), and an interstitial deletion of the long arm of chromosome 20, del(20)(q), are the most frequent anomalies in the bone marrow of patients with Shwachman-Diamond syndrome, which is caused in most cases by mutations of the SBDS gene. These clonal changes imply milder haematological symptoms and lower risk of myelodysplastic syndromes and acute myeloid leukaemia, thanks to already postulated rescue mechanisms. Results Bone marrow from fourteen patients exhibiting either the i(7)(q10) or the del(20)(q) and coming from two large cohorts of patients, were subjected to chromosome analyses, Fluorescent In Situ Hybridization with informative probes and array-Comparative Genomic Hybridization. One patient with the i(7)(q10) showed a subsequent clonal rearrangement of the normal chromosome 7 across years. Four patients carrying the del(20)(q) evolved further different del(20)(q) independent clones, within a single bone marrow sample, or across sequential samples. One patient with the del(20)(q), developed a parallel different clone with a duplication of chromosome 3 long arm. Eight patients bore the del(20)(q) as the sole chromosomal abnormality. An overall overview of patients with the del(20)(q), also including cases already reported, confirmed that all the deletions were interstitial. The loss of material varied from 1.7 to 26.9 Mb and resulted in the loss of the EIF6 gene in all patients. Conclusions Although the i(7)(q) and the del(20)(q) clones are frequent and clinically benign in Shwachman Diamond-syndrome, in the present work we show that they may rearrange, may be lost and then reconstructed de novo, or may evolve with independent clones across years. These findings unravel a striking selective pressure exerted by SBDS deficiency driving to karyotype instability and to specific clonal abnormalities.

Background: Endometrial cancer (EC) is a common gynecological malignancy, and the prognosis of advanced EC is unsatisfactory. The deregulated expression of RNA-binding proteins (RBPs) is closely associated with the occurrence and development of cancer. However, the role of RBPs in EC remains unclear. The aim of this study was to validate the prognostic values of RBPs combined with clinical factors. Methods: We downloaded the RNA sequencing and clinical data for EC from The Cancer Genome Atlas (TCGA) database. R software was used to identify the differentially expressed RBPs. Univariate and multivariate Cox proportional hazards regression analyses were performed to predict the 4 overall survival (OS)-related RBPs. We then constructed a nomogram combining the 4-RBP signature with clinical risk factors to assess the prognostic power. Furthermore, we validated the expression of 4 RBPs in our patient samples using quantitative real-time polymerase chain reaction (qRT-PCR) and explored the effect of cold-inducible RNA-binding protein (CIRBP) on EC tumor growth using cell proliferation experiments. Results: It is found that Shwachman-Bodian-Diamond syndrome (SBDS), CIRBP, MRPL15, and CELF4 were significantly related to the prognosis of EC patients. In addition, the nomogram showed better performance in OS predictions than the International Federation of Gynecology and Obstetrics (FIGO) stage. The qRT-PCR results showed that low CIRBP expression was associated with cell proliferation. Conclusions: In our study, we constructed a 4-RBP signature-based nomogram combined with clinical factors in EC that could effectively predict the prognosis of EC patients. The results provide novel insights into the development of treatment targets and prognostic molecular markers in EC. [ABSTRACT FROM AUTHOR]

Background: Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive ribosomopathy mainly characterized by exocrine pancreatic insufficiency, skeletal alterations, neutropenia, and a relevant risk of hematological transformation. At least 90% of SDS patients have pathogenic variants in SBDS, the first gene associated with the disease with very low allelic heterogeneity; three variants, derived from events of genetic conversion between SBDS and its pseudogene, SBDSP1, provided the alleles observed in about 62% of SDS patients. Methods: We performed a reanalysis of the available WES files of a group of SDS patients with biallelic SBDS pathogenic variants, studying the results by next bioinformatic and protein structural analysis. Parallelly, careful clinical attention was given to the patient focused in this study. Results: We found and confirmed in one SDS patient a germline heterozygous missense variant (c.100T>C; p.Phe34Leu) in the EIF6 gene. This variant, inherited from his mother, has a very low frequency, and it is predicted as pathogenic, according to several in silico prediction tools. The protein structural analysis also envisages the variant could reduce the binding to the nascent 60S ribosomal. Conclusion: This study focused on the hypothesis that the EIF6 germline variant mimics the effect of somatic deletions of chromosome 20, always including the locus of this gene, and similarly may rescue the ribosomal stress and ribosomal dysfunction due to SBDS mutations. It is likely that this rescue may contribute to the stable and not severe hematological status of the proband, but a definite answer on the role of this EIF6 variant can be obtained only by adding a functional layer of evidence. In the future, these results are likely to be useful for selected cases in personalized medicine and therapy. [ABSTRACT FROM AUTHOR]

Introduction. Shwachman-Diamond Syndrome (SDS) is an autosomal-recessive disorder characterized by neutropenia, pancreatic exocrine insufficiency, skeletal dysplasia, and an increased risk for leukemic transformation. Biallelic mutations in the SBDS gene have been found in about 90% of patients. The clinical spectrum of SDS in patients is wide, and variability has been noticed between different patients, siblings, and even within the same patient over time. Herein, we present two SDS siblings (UPN42 and UPN43) carrying the same SBDS mutations and showing relevant differences in their phenotypic presentation. Study aim. We attempted to understand whether other germline variants, in addition to SBDS, could explain some of the clinical variability noticed between the siblings. Methods. Whole-exome sequencing (WES) was performed. Human Phenotype Ontology (HPO) terms were defined for each patient, and the WES data were analyzed using the eVai and DIVAs platforms. Results. In UPN43, we found and confirmed, using Sanger sequencing, a novel de novo variant (c.10663G > A, p.Gly3555Ser) in the KMT2A gene that is associated with autosomal-dominant Wiedemann–Steiner Syndrome. The variant is classified as pathogenic according to different in silico prediction tools. Interestingly, it was found to be related to some of the HPO terms that describe UPN43. Conclusions. We postulate that the KMT2A variant found in UPN43 has a concomitant and co-occurring clinical effect, in addition to SBDS mutation. This dual molecular effect, supported by in silico prediction, could help to understand some of the clinical variations found among the siblings. In the future, these new data are likely to be useful for personalized medicine and therapy for selected cases. [ABSTRACT FROM AUTHOR]

Rationale: Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive genetic disease, the diagnosis is a big challenge for clinician, as the clinical manifestations of the disease are diverse. Here, we report a girl who diagnosed with SDS with the symptoms of recurrent fever, elevated transaminase levels, and granulocytosis. The aspects of diagnosis and treatment were discussed and a literature review was conducted., Patient Concerns: A 15-month-old girl admitted to our hospital because of recurrent fever, granulocytopenia, and elevated transaminase levels., Diagnosis and Interventions: The compound heterozygous variant of Shwachman-Bodian-Diamond syndrome c.258 + 2T > C:p.84Cfs3 and c.96C > G:p.Y32* were detected after sequencing the blood samples from the patient and her parents. Finally, she was diagnosed with SDS and she was treated with compound glycyrrhizin, granulocyte-colony stimulating factor, and antibiotic in the case of co-infection., Outcomes: During the follow-up, her liver function showed the level of transaminases decreased and she rarely had infection after the age of 15 months although neutropenia is still present., Lessons: Patients with SDS lacks typical clinical symptoms, which presents a huge challenge for clinicians. Genetic testing techniques is playing an important role in the diagnosis of diseases. This patient without typical clinical manifestations such as exocrine pancreatic insufficiency and skeletal abnormality, we report this case aimed to strengthen the understanding of the disease., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Shwachman–Diamond syndrome (SDS) is a rare autosomal recessive ribosomopathy mainly characterized by exocrine pancreatic insufficiency, skeletal alterations, neutropenia, and a relevant risk of hematological transformation. At least 90% of SDS patients have pathogenic variants in SBDS, the first gene associated with the disease with very low allelic heterogeneity; three variants, derived from events of genetic conversion between SBDS and its pseudogene, SBDSP1, provided the alleles observed in about 62% of SDS patients.Methods: We performed a reanalysis of the available WES files of a group of SDS patients with biallelic SBDS pathogenic variants, studying the results by next bioinformatic and protein structural analysis. Parallelly, careful clinical attention was given to the patient focused in this study.Results: We found and confirmed in one SDS patient a germline heterozygous missense variant (c.100T>C; p.Phe34Leu) in the EIF6 gene. This variant, inherited from his mother, has a very low frequency, and it is predicted as pathogenic, according to several in silico prediction tools. The protein structural analysis also envisages the variant could reduce the binding to the nascent 60S ribosomal.Conclusion: This study focused on the hypothesis that the EIF6 germline variant mimics the effect of somatic deletions of chromosome 20, always including the locus of this gene, and similarly may rescue the ribosomal stress and ribosomal dysfunction due to SBDS mutations. It is likely that this rescue may contribute to the stable and not severe hematological status of the proband, but a definite answer on the role of this EIF6 variant can be obtained only by adding a functional layer of evidence. In the future, these results are likely to be useful for selected cases in personalized medicine and therapy.

The Shwachman–Diamond Syndrome (SDS) is an autosomal recessive disease whose majority of patients display mutations in a ribosome assembly protein named Shwachman–Bodian–Diamond Syndrome protein (SBDS). A specific therapy for treating this rare disease is missing, due to the lack of knowledge of the molecular mechanisms responsible for its pathogenesis. Starting from the observation that SBDS single-point mutations, localized in different domains of the proteins, are responsible for an SDS phenotype, we carried out the first comparative Molecular Dynamics simulations on three SBDS mutants, namely R19Q, R126T and I212T. The obtained 450-ns long trajectories were compared with those returned by both the open and closed forms of wild type SBDS and strongly indicated that two distinct conformations (open and closed) are both necessary for the proper SBDS function, in full agreement with recent experimental observations. Our study supports the hypothesis that the SBDS function is governed by an allosteric mechanism involving domains I and III and provides new insights into SDS pathogenesis, thus offering a possible starting point for a specific therapeutic option. [ABSTRACT FROM AUTHOR]