Responsive Megaloblastic Anemia Research Articles

Thiamine Responsive Megaloblastic Anemia and Deafness: A rare case of Roger’s syndrome with successful hearing rehabilitation by Cochlear Implantation

Thiamine Responsive Megaloblastic Anemia and Deafness: A rare case of Roger’s syndrome with successful hearing rehabilitation by Cochlear Implantation

Novel Homozygous Variant in the SLC19A2 Gene Causing Thiamine Responsive Megaloblastic Anemia Syndrome: A Disease to Be Considered in Diabetes Clinics

Novel Homozygous Variant in the SLC19A2 Gene Causing Thiamine Responsive Megaloblastic Anemia Syndrome: A Disease to Be Considered in Diabetes Clinics

Тиамин-зависимая мегалобластная анемия (синдром Роджерса) у ребенка трех лет

Thiamine responsive megaloblastic anemia (TRMA), or Rogers syndrome, is a rare autosomal recessive disease characterized by the development of megaloblastic anemia, diabetes mellitus, and progressive sensorineural hearing loss. In some cases, the syndrome causes ophthalmological disorders (retinitis pigmentosa, optic nerve atrophy, maculopathy, nystagmus), heart diseases (paroxysmal atrial fibrillation, supraventricular tachycardia, congenital heart defects, intracardiac conduction disorders) and neurological disorders (epilepsy, cerebrovascular accidents). TRMA develops due to a mutation in the SLC19A2 gene, which encodes ThTr-1 (thiamine transporter protein) expressed in hematopoietic stem cells, pancreatic beta cells, and inner ear cells. The article presents a clinical case of TRMA in a three-year-old child, with the onset in the first year of life, manifesting as anemia and diabetes mellitus. Thiamine therapy ensured a pronounced positive dynamics: the patient's peripheral blood parameters normalized. The clinical description and the literature review herein aim to raise awareness of doctors of all specialties about this syndrome. An atypical clinical picture and lack of knowledge about TRMA often delay the diagnosis and start of therapy.

An Italian case series' description of thiamine responsive megaloblastic anemia syndrome: importance of early diagnosis and treatment

BackgroundIndividuals with thiamine-responsive megaloblastic anemia (TRMA) mainly manifest macrocytic anemia, sensorineural deafness, ocular complications, and nonautoimmune diabetes. Macrocytic anemia and diabetes may be responsive to high-dosage thiamine treatment, in contrast to sensorineural deafness. Little is known about the efficacy of thiamine treatment on ocular manifestations.Cases presentationOur objective is to report data from four Italian TRMA patients: in Cases 1, 2 and 3, the diagnosis of TRMA was made at 9, 14 and 27 months. In 3 out of 4 subjects, thiamine therapy allowed both normalization of hyperglycemia, with consequent insulin suspension, and macrocytic anemia. In all Cases, thiamine therapy did not resolve the clinical manifestation of deafness. In Cases 2 and 3, follow-up showed no blindness, unlike Case 4, in which treatment was started for megaloblastic anemia at age 7 but was increased to high doses only at age 25, when the genetic diagnosis of TRMA was performed.ConclusionsEarly institution of high-dose thiamine supplementation seems to prevent the development of retinal changes and optic atrophy in TRMA patients. The spectrum of clinical manifestations is broad, and it is important to describe known Cases to gain a better understanding of this rare disease.

A long-term follow-up of a case of Rogers syndrome, Thiamine responsive megaloblastic anemia

Thiamine-responsive megaloblastic anemia (TRMA) also known as Rogers syndrome is a rare autosomal recessive disorder characterized by megaloblastic anemia, diabetes mellitus, and progressive sensorineural deafness. The disease can be manifested anytime between infancy and adolescence, and all the cardinal findings may not be present at the time of the diagnosis. The main defect lies in the active thiamine uptake into cells which is disturbed. Not many cases have been reported about the long-term follow-up of children with this disorder and their associated complications. We hereby report a 14 years follow-up of a girl with Rogers syndrome diagnosed at toddler age with nonresponsive anemia and diabetes and further progressed to have sensorineural hearing loss. Her clinical exome study showed a mutation in the SLC19A2 gene. This experience illustrates the relevance of a detailed evaluation and regular follow-up to assess the progression of the syndrome till her pubertal age.

An extremely rare case of Rogers syndrome or thiamine responsive megaloblastic anemia.

Rogers syndrome is an extremely rare autosomal recessive syndrome of which only 100 cases are known worldwide. It is characterized by thiamine-responsive megaloblastic anaemia, diabetes mellitus and sensorineural deafness. It results from the deficiency of a thiamine transporter protein. We herein report a 16-year-old Indian male referred to our centre with complaints of refractory anaemia, deafness, diabetes pulmonary arterial hypertension and tricuspid regurgitation. Based on the clinical features and haematologic picture and dramatic response of anaemia to thiamine therapy the possibility of a TRMA was considered. Sequencing analysis for TRMA revealed a homozygous c.242dup (p.Tyr81Ter) mutation of the SLC19A2 gene.

Endoplasmic Reticulum Stress in the Pathogenesis of Hyperglycemia Induced by Thiamine-Responsive Megaloblastic Anemia.

Thiamine responsive megaloblastic anemia (TRMA) is a genetic disease caused by SLC19A2 gene mutation. This study aimed to preliminarily explore the relationship between endoplasmic reticulum stress (ERS)-PERK signaling pathway and the pathogenesis of hyperglycemia induced by TRMA. Islet β (INS.1 and β-TC-6) and HEK293T cell line models with stable overexpression of SLC19A2 and SLC19A2 (c.1409insT) were established. The cells were divided into empty virus group (control), wild-type group (overexpressed SLC19A2), and mutation group (overexpressed SLC19A2 (c.1409insT)). Quantitative reverse transcription-polymerase chain reaction (RT-qPCR) and western blotting were used to detect the expression levels of ERS-PERK signaling pathway-related proteins, including glucose-regulated protein 78 (GRP78), protein kinase R-like ER kinase (PERK), and eukaryotic initiation factor 2 (eIF2α), activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP) in islet β cells. Protein localization was assessed by immunofluorescence staining. Compared with the control group, the mRNA expression levels of SLC19A2 in wild-type and mutant islet β cells (INS.1 and β-TC-6) and HEK293T cells were significantly upregulated (all p < 0.05). Compared with the control group and the wild-type group, the mRNA expression levels of GRP78, PERK, eIF2α, ATF4, and CHOP were increased (all p < 0.05) in the mutant islet β cells; the protein expression levels of PERK, GRP78, and eIF2α were elevated (all p < 0.05). In addition, the results of immunofluorescence staining showed that SLC19A2 (c.1409insT) mutation changed the localization of the proteins in the cells. Thus, they were not located on the cell surface, but in the cytoplasm and nuclei, and protein aggregation occurred in the cytoplasm. 1. Islet β and HEK293Tcell lines, stably overexpressing SLC19A2 and SLC19A2 (c.1409insT) mutations, were successfully constructed. 2. SLC19A2 (c.1409insT) mutation could raise the expression levels of ERS-PERK signaling pathway-related proteins (GRP78, PERK, eIF2α, ATF4, and CHOP), and activate apoptosis pathway. 3. SLC19A2 (c.1409insT) mutation could change the localization of proteins and produce protein aggregation in cells. It could lead to protein misfolding and ERS, which would participate in the pathological mechanism of hyperglycemia induced by TRMA.

ROGERS SYNDROME-THIAMINE RESPONSIVE MEGALOBLASTIC ANEMIA SYNDROME: CASE REPORT

Thiamine responsive megaloblastic anemia (TRMA) encompasses a complex syndrome of anemia, sensorineural hearing loss and Diabetes Mellitus. We report a 06 years old male child with pallor, bilateral sensorineural hearing loss, Diabetes Mellitus, megaloblastic anemia, retinitis pigmentosa and a normal response to water deprivation test. Child responded well to high doses of thiamine treatment. Rogers Syndrome, a spectrum disease, should be kept in mind in differential diagnosis of Diabetes Mellitus and megaloblastic anemia in population with frequent consanguinity. Thorough medical and family history and physical examination are vital for diagnosis. Prompt diagnosis, use of careful clinical monitoring and supportive care can relieve the debilitating symptoms. Key Words: Diabetes Mellitus, Megaloblastic anemia, Sensorineural hearing loss, Rogers syndrome.

Monogenic diabetes: A single center experience from South India

Monogenic forms of diabetes in children are frequently misclassified as either type 1 diabetes or young-onset type 2 diabetes. There is a paucity of literature regarding pediatric monogenic diabetes in the Indian population. A retrospective analysis of case records of 37 children with monogenic diabetes who were diagnosed between 2008 and 2019 in a South Indian tertiary care center was performed. The write-up describes the clinical, biochemical, and genetic characterization of these patients with the diagnoses of neonatal diabetes mellitus (15 patients), MODY (five patients), and various forms of syndromic diabetes (13 with Wolfram syndrome, two with H syndrome, one with mitochondrial diabetes, and one with thiamine responsive megaloblastic anemia).

Roger Syndrome Case Report

Roger syndrome (Thiamin Responsive Megaloblastic Anemia Syndrome), is characterized by megaloblastic anemia, deafness and diabetes mellitus. It is an autosomal recessive disorder due to mutation in SLC 19A2 gene that leads to defective thiamine transport protein. So, thiamine is not absorbed and effectively utilized by body from diet.

Frameshift variance in SLC19A2 gene causing thiamine responsive megaloblastic anemia (TRMA): a case report from Pakistan

Thiamine responsive megaloblastic anemia syndrome is a rare genetic disorder usually associated with sensorineural deafness, megaloblastic anemia, and/or diabetes mellitus due to mutations in SLC19A2, encoding a thiamine transporter protein. In this case, we report a 2.5-year-old baby boy born to consanguineous parents. He was noted to be deaf and mute during his first year of life. He was diagnosed with anemia at the age of 15 months and required blood transfusion twice. The cause of anemia was not established and it was attributed secondary to some viral infection. At the age of 2 years, he was diagnosed with DM. The diagnosis of TRMA had been made during his evaluations for uncontrolled blood glucose, sensorineural deafness, and anemia. After few weeks of thiamine replacement, his hemoglobin increased to normal values; his sugars improved but had no changes in his deafness. Analysis of all coding regions and exon/intron boundaries of the SLC19A2 gene by Sanger sequencing. A p,Leu208fs homozygous frame shift variant is identified in the SLC19A2 gene, located on the Exon 2 and DNA description is c.623dup. This variant is predicted to be pathogenic and diagnosis of TRMA syndrome is confirmed. The diagnosis of TRMA should be kept in mind in differential diagnosis of DM with anemia and or sensorineural hearing loss. Particularly in the populations where the consanguinity is frequent as diagnosis has great impact on management.

The Clinical Journey of Patients with Riboflavin Transporter Deficiency Type 2.

To identify symptoms and health care interactions with patients with riboflavin transporter deficiency (RTD) type 2 prior to diagnosis. Parents of children with riboflavin transporter deficiency type 2 (n = 10) were interviewed to collect data on the patient's clinical journey. The average diagnostic delay was 27.6 months. Neurologists were the most commonly visited clinician (90%). Common symptoms during the first year of the patient's clinical journey included abnormal gait and/or ataxia (70%), nystagmus (50%), and upper body muscle weakness (40%). Prior to diagnosis, optic atrophy, sleep apnea, breath-holding spells, and dysphagia were commonly observed. Hearing loss was only reported in 40% of subjects prior to diagnosis. Riboflavin responsive megaloblastic anemia is reported for the first time. Mitochondrial disease was the most common suspected diagnosis (30%). Despite clinical variability, common early symptoms of riboflavin transporter deficiency type 2 exist that can better allow clinicians to more rapidly identify riboflavin transporter deficiency type 2.

Thiamine Responsive Megaloblastic Anemia – A treatable rarity

Thiamine Responsive Megaloblastic Anemia – A treatable rarity

Rare case of diabetes mellitus, sensorineural hearing loss, and refractory megaloblastic anemia: SLC19A2 mutation

Reporting a rare and treatable case of thiamine responsive Megaloblastic Anemia with Sensori-neural Hearing Loss with Diabetes Mellitus in a 6 year old child due to SLC19A2 mutation. Simple thiamine treatment is cost effective and can reverse this disorder except hearing loss.

Recurrent Stroke in a Child with TRMA Syndrome and SLC19A2 Gene Mutation.

Here we report a 5-month-old boy with thiamine Responsive Megaloblastic Anemia syndrome (TRMA syndrome) with several attacks of stroke, admitted to Mofid Children's Hospital, Tehran, Iran, in 2016. In addition to the cardinal clinical manifestations of the syndrome, other manifestations comprise thiamine-responsive megaloblastic anemia, diabetes mellitus, and sensor neural hearing loss. The patient showed the ischemic attack of stroke. Megaloblastic anemia and diabetes were diagnosed at 8 months and was successfully treated with vitamin and insulin prescription. After treatment of thiamine, diabetes was controlled and insulin was discontinued. In spite of the thiamine administration, the second stroke as hemorrhagic stroke occurred in the patient after a few months. TRAMA is inherited in an autosomal recessive manner. TRMA was confirmed by mutation in SLC19A2. A homozygous splice site variant was detected in SLC19A2 gene. Stroke was not reported in this syndrome (only in one report about one attack in an adult patient) but in this patient, several attacks of stroke were reported before and after thiamin administration.

A Thiamine Responsive Megaloblastic Anemia Presented with Hypertriglyceridemia and Auto-immune Diabetes

Background: Thiamine responsive megaloblastic anemia syndrome (TRMA) is an autosomal recessive disorder characterized by non type 1 diabetes mellitus (DM), sensorineural hearing loss and megaloblastic anemia and caused by mutations in SLC19A2 gene, encoding a thiamine transporter protein. Case: A 3-month-old male infant presented with megaloblastic anemia, DM, patent ductus arteriosus and hypertriglyceridemia. His autoimmune markers for DM were positive but with the additional finding of sensorineural deafness he was diagnosed with TRMA and thiamine therapy was started. His anemia was improved and insulin needs decreased and his genetic studies revealed a homozygous frameshift mutation, c.641del within coding region of SLC19A2 gene. Conclusion: Clinical presentation of TRMA could be highly variable and some co-existence could perplex physicians, but this diagnosis should be considered in all patients with DM and anemia and further assessment should be done.

Novel nonsense mutation (p.Ile411Metfs*12) in the SLC19A2 gene causing Thiamine Responsive Megaloblastic Anemia in an Indian patient

Thiamine-responsive megaloblastic anemia (TRMA), an autosomal recessive disorder, is caused by mutations in SLC19A2 gene encodes a high affinity thiamine transporter (THTR-1). The occurrence of TRMA is diagnosed by megaloblastic anemia, diabetes mellitus, and sensorineural deafness. Here, we report a female TRMA patient of Indian descent born to 4th degree consanguineous parents presented with retinitis pigmentosa and vision impairment, who had a novel homozygous mutation (c.1232delT/ter422; p.Ile411Metfs*12) in 5th exon of SLC19A2 gene that causes premature termination of hTHTR-1. PROSITE analysis predicted to abrogate GPCRs family-1 signature motif in the variant by this mutation c.1232delT/ter422, suggesting uncharacteristic rhodopsin function leading to cause RP clinically. Thiamine transport activity by the clinical variant was severely inhibited than wild-type THTR-1. Confocal imaging had shown that the variant p.I411Mfs*12 is targeted to the cell membrane and showed no discrepancy in membrane expression than wild-type. Our findings are the first report, to the best of our knowledge, on this novel nonsense mutation of hTHTR-1 causing TRMA in an Indian patient through functionally impaired thiamine transporter activity.

English

Thiamine responsive megaloblastic anemia (TRMA) is an autosomal recessive disorder, which is caused by loss of function mutations in the SLC19A2 gene. TRMA is characterized by anemia, deafness, and diabetes mellitus. We now report two sisters, the eldest of which presented to a different hospital during childhood with sensorineural deafness, which was treated with a hearing prosthesis, insulin requiring diabetes, megaloblastic anemia. The younger sister is also affected with sensorineural deafness along with diabetes and megaloblastic anemia. Because a diagnosis of TRMA was suspected, therapy with insulin and thiamine was started to which the child is responding. Diabetes associated with deafness and megaloblastic anemia, suggests a diagnosis of TRMA.

Identification of four SLC19A2 mutations in four Chinese thiamine responsive megaloblastic anemia patients without diabetes

Identification of four SLC19A2 mutations in four Chinese thiamine responsive megaloblastic anemia patients without diabetes

Thiamine responsive megaloblastic anemia: The puzzling phenotype

Thiamine responsive megaloblastic anemia (TRMA) is characterized by a triad of megaloblastic anemia, non-type 1 diabetes mellitus and sensorineural deafness. Other clinical findings have been described in few cases. The SLC19A2 gene on chromosome 1q 23.3 is implicated in all cases with TRMA. Our aim is to discuss the clinical manifestations of all Omani children diagnosed with TRMA and determine genotype-phenotype relationship. Clinical and laboratory data of all patients diagnosed in Oman were retrospectively collected. Mutation analysis of affected families was conducted using two Microsatellite markers. Genotyping was performed with fluorescent-labeled PCR primers. To define the deletion breakpoint region, PCR reactions were carried out using different primer pairs located at the introns 3 and 3'-untranslated region with Expand Long Template PCR kit. A total of six children have been diagnosed with this syndrome. They were five females and one male. They all presented with sensorineural deafness at birth while the age of anemia presentation ranged between 6 weeks to 19 months. They all belong to same family with complex interfamilial marriages and presented with the typical triad. Of interest is the very rare presentation of one patient with Uhl cardiac anomaly (total absence of right ventricular myocardium with apposition of endocardium and pericardium) that has never been described before in patients with TRMA. All patients have a novel large deletion of 5,224 bp involving exons 4, 5, and 6 of SLC19A2. TRMA is a disease of expanding phenotypic spectrum with poor genotype-phenotype correlation.