Meglitinide analogues in adolescent patients with HNF1A-MODY (MODY 3)

Decoding MODY: exploring genetic roots and clinical pathways

Purpose

Maturity-onset diabetes of the young (MODY) is a transformative factor in today's pattern of diabetes care. The definition of its genetic basis brings insight into the diabetes processes, opening up possibilities for its early detection through public health strategies and improvement in precision medicine. Current knowledge on MODY has been brought together in this review.

Methods

Extensive literature review on PubMed and Google Scholar databases was conducted. Studies encompassing (1) genetic underpinnings and their types, (2) the significance of its biomarkers, and (3) diagnostic techniques and treatment modalities were focused upon.

Results

The disease accounts for 1-2% of all cases of diabetes and is usually misdiagnosed as either Type 1 or Type 2 diabetes. Several genes are involved in the appropriate functioning of pancreatic β-cells and mutations in these genes lead to an impairment in glucose metabolism and insulin secretion. A mild degree of hyperglycaemia, but without ketosis, is typical of MODY, seen mostly in adolescents and young adults. Treatment varies, including sulfonylureas for HNF1A and HNF4A mutations, lifestyle management for GCK mutations, and emerging therapies like GLP1 receptor agonists.

Conclusion

Proper genetic diagnosis is cardinal to the best management of MODY. Genetic and clinical advances have been impressive in monogenic diabetes, but further research in novel therapies is needed to optimise outcomes with precision medicine.

Monogenic Diabetes: A Comprehensive Overview and Therapeutic Management of Subtypes of Mody

BACKGROUND

Monogenic diabetes often occurs as a result of single-gene mutations. The illness is minimally affected by environmental and behavioral factors, and it constitutes around one to five percent of all cases of diabetes.

METHODS

Newborn diabetes mellitus (NDM) and maturity-onset diabetes of the young (MODY) are the predominant causes of monogenic diabetes, accounting for a larger proportion of cases, while syndromic diabetes represents a smaller percentage. MODY, a group of inherited non-autoimmune diabetes mellitus disorders, is quite common. However, it remains frequently misdiagnosed despite increasing public awareness. The condition is characterized by insulin resistance, the development of diabetes at a young age (before 25 years), mild high blood sugar levels, inheritance in an autosomal dominant pattern, and the preservation of natural insulin production.

RESULTS

Currently, there are 14 distinct subtypes of MODY that have been identified. Each subtype possesses distinct characteristics in terms of their frequency, clinical symptoms, severity of diabetes, related complications, and response to medicinal interventions. Due to the clinical similarities, lack of awareness, and high expense of genetic testing, distinguishing between type I (T1D) and type II diabetes mellitus (T2D) can be challenging, resulting in misdiagnosis of this type of diabetes. As a consequence, a significant number of individuals are being deprived of adequate medical attention. Accurate diagnosis enables the utilization of novel therapeutic strategies and enhances the management of therapy in comparison to type II and type I diabetes.

CONCLUSION

This article offers a concise overview of the clinical subtypes and characteristics of monogenic diabetes. Furthermore, this article discusses the various subtypes of MODY, as well as the process of diagnosing, managing, and treating the condition. It also addresses the difficulties encountered in detecting and treating MODY.

Monogenic Defects of Beta Cell Function: From Clinical Suspicion to Genetic Diagnosis and Management of Rare Types of Diabetes

Monogenic defects of beta cell function refer to a group of rare disorders that are characterized by early-onset diabetes mellitus due to a single gene mutation affecting insulin secretion. It accounts for up to 5% of all pediatric diabetes cases and includes transient or permanent neonatal diabetes, maturity-onset diabetes of the young (MODY), and various syndromes associated with diabetes. Causative mutations have been identified in genes regulating the development or function of the pancreatic beta cells responsible for normal insulin production and/or release. To date, more than 40 monogenic diabetes subtypes have been described, with those caused by mutations in HNF1A and GCK genes being the most prevalent. Despite being caused by a single gene mutation, each type of monogenic diabetes, especially MODY, can appear with various clinical phenotypes, even among members of the same family. This clinical heterogeneity, its rarity, and the fact that it shares some features with more common types of diabetes, can make the clinical diagnosis of monogenic diabetes rather challenging. Indeed, several cases of MODY or syndromic diabetes are accurately diagnosed in adulthood, after having been mislabeled as type 1 or type 2 diabetes. The recent widespread use of more reliable sequencing techniques has improved monogenic diabetes diagnosis, which is important to guide appropriate treatment and genetic counselling. The current review aims to summarize the latest knowledge on the clinical presentation, genetic confirmation, and therapeutic approach of the various forms of monogenic defects of beta cell function, using three imaginary clinical scenarios and highlighting clinical and laboratory features that can guide the clinician in reaching the correct diagnosis.

Precision treatment of beta-cell monogenic diabetes: a systematic review

BACKGROUND

Beta-cell monogenic forms of diabetes have strong support for precision medicine. We systematically analyzed evidence for precision treatments for GCK-related hyperglycemia, HNF1A-, HNF4A- and HNF1B-diabetes, and mitochondrial diabetes (MD) due to m.3243 A > G variant, 6q24-transient neonatal diabetes mellitus (TND) and SLC19A2-diabetes.

METHODS

The search of PubMed, MEDLINE, and Embase for individual and group level data for glycemic outcomes using inclusion (English, original articles written after 1992) and exclusion (VUS, multiple diabetes types, absent/aggregated treatment effect measures) criteria. The risk of bias was assessed using NHLBI study-quality assessment tools. Data extracted from Covidence were summarized and presented as descriptive statistics in tables and text.

RESULTS

There are 146 studies included, with only six being experimental studies. For GCK-related hyperglycemia, the six studies (35 individuals) assessing therapy discontinuation show no HbA1c deterioration. A randomized trial (18 individuals per group) shows that sulfonylureas (SU) were more effective in HNF1A-diabetes than in type 2 diabetes. Cohort and case studies support SU's effectiveness in lowering HbA1c. Two cross-over trials (each with 15-16 individuals) suggest glinides and GLP-1 receptor agonists might be used in place of SU. Evidence for HNF4A-diabetes is limited. Most reported patients with HNF1B-diabetes (N = 293) and MD (N = 233) are on insulin without treatment studies. Limited data support oral agents after relapse in 6q24-TND and for thiamine improving glycemic control and reducing/eliminating insulin requirement in SLC19A2-diabetes.

CONCLUSION

There is limited evidence, and with moderate or serious risk of bias, to guide monogenic diabetes treatment. Further evidence is needed to examine the optimum treatment in monogenic subtypes.

A Woman With HNF1A-Associated Monogenic Diabetes Treated Successfully With Repaglinide Monotherapy

Background/Objective

Monogenic diabetes is a rare type of diabetes that is commonly misdiagnosed as type 1 or 2 diabetes mellitus, which adversely impacts patient care. Such cases are particularly challenging given the heterogeneity in presentation and overlap with other types of diabetes. As the sole use of meglitinides, especially repaglinide, to treat HNF1A-associated monogenic diabetes has been rarely reported in a few other observational studies, we describe a patient who was treated successfully with repaglinide.

Case Report

A 38-year-old woman with type 1 diabetes mellitus, congenital deafness, chronic kidney disease, and retinopathy presented with difficulty controlling her blood glucose levels. Although initially treated with insulin, she had periods of noncompliance with insulin without experiencing diabetic ketoacidosis. Although on insulin therapy, she experienced multiple episodes of hypoglycemia. The laboratory tests showed a hemoglobin A1c level of 10.8%, c-peptide level of 2.7 ng/mL (1.1-4.4 ng/mL), glucose level of 192 mg/dL, creatinine level of 1.23 ng/dL, and severely increased microalbumin-to-creatinine ratio of 638 mg/g (normal range, 0-29 mg/g). Pancreatic autoantibodies were negative. Genetic testing revealed a diagnosis of HNF1A-associated monogenic diabetes (c. 1340C>T (p.P447L)). She was ultimately treated with repaglinide after trials of sulfonylureas and dipeptidyl peptidase 4 inhibitors led to frequent hypoglycemia and a significant increase in the hemoglobin A1c level, respectively.

Discussion

This case highlights the importance of correctly diagnosing monogenic diabetes and reports the successful use of repaglinide to treat HNF1A-associated monogenic diabetes.

Conclusion

Patients with HNF1A-associated monogenic diabetes who do not achieve euglycemia with sulfonylureas and insulin may be successfully treated with repaglinide monotherapy.

Advancements in pharmacotherapy options for treating diabetes ‎in children and adolescents

INTRODUCTION

This study compares diabetes management between pediatric and adult patients and identifies treatment challenges and gaps.

AREAS COVERED

We searched PubMed and Clinicaltrails.gov databases for studies published from 2001 to 2023 on diabetes management in different age groups.

EXPERT OPINION

Research shows children have lower insulin sensitivity, clearance, and β cell function than adults. The US FDA only allows insulin, metformin, and liraglutide as antidiabetic medication options for children. However, some off-label drugs, like meglitinides, sulfonylureas, and alogliptin, have demonstrated positive results in treating certain types of diabetes caused by gene mutations. It's crucial to adopt personalized and precise approaches to managing diabetes in pediatrics, which vary from those used for adult patients. New studies support the classification of type 2 diabetes into several subtypes based on age, BMI, glycemia, homeostasis model estimates, varying insulin resistance, ‎different rates of complications‎, and islet ‎autoantibodies. With this insight, prevention, treatment, and precision medicine of diabetes might be changed. More research is necessary to assess the safety and efficacy of different antidiabetic drugs and improve diabetes treatment for children and adolescents.

Genetic perspectives on childhood monogenic diabetes: Diagnosis, management, and future directions

Monogenic diabetes is caused by one or even more genetic variations, which may be uncommon yet have a significant influence and cause diabetes at an early age. Monogenic diabetes affects 1 to 5% of children, and early detection and gene-tically focused treatment of neonatal diabetes and maturity-onset diabetes of the young can significantly improve long-term health and well-being. The etiology of monogenic diabetes in childhood is primarily attributed to genetic variations affecting the regulatory genes responsible for beta-cell activity. In rare instances, mutations leading to severe insulin resistance can also result in the development of diabetes. Individuals diagnosed with specific types of monogenic diabetes, which are commonly found, can transition from insulin therapy to sulfonylureas, provided they maintain consistent regulation of their blood glucose levels. Scientists have successfully devised materials and methodologies to distinguish individuals with type 1 or 2 diabetes from those more prone to monogenic diabetes. Genetic screening with appropriate findings and interpretations is essential to establish a prognosis and to guide the choice of therapies and management of these interrelated ailments. This review aims to design a comprehensive literature summarizing genetic insights into monogenetic diabetes in children and adolescents as well as summarizing their diagnosis and mana-gement.

Systematic Review of Treatment of Beta-Cell Monogenic Diabetes

Background

Beta-cell monogenic forms of diabetes are the area of diabetes care with the strongest support for precision medicine. We reviewed treatment of hyperglycemia in GCK-related hyperglycemia, HNF1A-HNF4A- and HNF1B-diabetes, Mitochondrial diabetes (MD) due to m.3243A>G variant, 6q24-transient neonatal diabetes (TND) and SLC19A2-diabetes.

Methods

Systematic reviews with data from PubMed, MEDLINE and Embase were performed for the different subtypes. Individual and group level data was extracted for glycemic outcomes in individuals with genetically confirmed monogenic diabetes.

Results

147 studies met inclusion criteria with only six experimental studies and the rest being single case reports or cohort studies. Most studies had moderate or serious risk of bias.For GCK-related hyperglycemia, six studies (N=35) showed no deterioration in HbA1c on discontinuing glucose lowering therapy. A randomized trial (n=18 per group) showed that sulfonylureas (SU) were more effective in HNF1A-diabetes than in type 2 diabetes, and cohort and case studies supported SU effectiveness in lowering HbA1c. Two crossover trials (n=15 and n=16) suggested glinides and GLP-1 receptor agonists might be used in place of SU. Evidence for HNF4A-diabetes was limited. While some patients with HNF1B-diabetes (n=301) and MD (n=250) were treated with oral agents, most were on insulin. There was some support for the use of oral agents after relapse in 6q24-TND, and for thiamine improving glycemic control and reducing insulin requirement in SLC19A2-diabetes (less than half achieved insulin-independency).

Conclusion

There is limited evidence to guide the treatment in monogenic diabetes with most studies being non-randomized and small. The data supports: no treatment in GCK-related hyperglycemia; SU for HNF1A-diabetes. Further evidence is needed to examine the optimum treatment in monogenic subtypes.

Treatment strategy for maturity-onset diabetes of the young 3 (MODY3): Experience with two sisters and their mother

Maturity onset diabetes of the young (MODY) is a relatively young-onset diabetes mellitus with an autosomal dominant inheritance. Among these phenotypes, MODY3, caused by mutations in HNF1A, is one of the most frequent. Although MODY3 is known to respond markedly to sulfonylureas (SU), many cases require insulin therapy. However, there are no clear guidelines for factors to consider when introducing antidiabetic drugs and insulin. This report describes a familial case in which an older sister was diagnosed with diabetes and subsequently with MODY3, followed by the onset of diabetes in the younger sister and mother. The elder sister initially denied insulin treatment and exhibited a suboptimal response to SU but finally agreed to insulin use. The mother initially selected insulin therapy because of the challenges associated with adherence to strict dietary therapy. Conversely, the younger sister responded positively to SU and maintained effective glycemic control. The management of MODY3, even though they have the same single-gene mutation and similar residual insulin secretion at diagnosis, should be flexibly individualized for each family member to ensure long-term adherence and appropriate glycemic control.

An Update on the Molecular and Cellular Basis of Pharmacotherapy in Type 2 Diabetes Mellitus

Diabetes mellitus (DM) is a chronic illness with an increasing global prevalence. More than 537 million cases of diabetes were reported worldwide in 2021, and the number is steadily increasing. The worldwide number of people suffering from DM is projected to reach 783 million in 2045. In 2021 alone, more than USD 966 billion was spent on the management of DM. Reduced physical activity due to urbanization is believed to be the major cause of the increase in the incidence of the disease, as it is associated with higher rates of obesity. Diabetes poses a risk for chronic complications such as nephropathy, angiopathy, neuropathy and retinopathy. Hence, the successful management of blood glucose is the cornerstone of DM therapy. The effective management of the hyperglycemia associated with type 2 diabetes includes physical exercise, diet and therapeutic interventions (insulin, biguanides, second generation sulfonylureas, glucagon-like peptide 1 agonists, dipeptidyl-peptidase 4 inhibitors, thiazolidinediones, amylin mimetics, meglitinides, α-glucosidase inhibitors, sodium-glucose cotransporter-2 inhibitors and bile acid sequestrants). The optimal and timely treatment of DM improves the quality of life and reduces the severe burden of the disease for patients. Genetic testing, examining the roles of different genes involved in the pathogenesis of DM, may also help to achieve optimal DM management in the future by reducing the incidence of DM and by enhancing the use of individualized treatment regimens.

Modulatory Effect of Medicinal Plants and Their Active Constituents on ATP-Sensitive Potassium Channels (KATP) in Diabetes

Hyperglycemia, which is a chronic metabolic condition caused by either a defect in insulin secretion or insulin resistance, is a hallmark of diabetes mellitus (DM). Sustained hyperglycemia leads to the onset and development of many health complications. Despite the number of available antidiabetic medications on the market, there is still a need for novel treatment agents with increased efficacy and fewer adverse effects. Many medicinal plants offer a rich supply of bioactive compounds that have remarkable pharmacological effects with less toxicity and side effects. According to published evidence, natural antidiabetic substances influence pancreatic β-cell development and proliferation, inhibit pancreatic β-cell death, and directly increase insulin output. Pancreatic ATP-sensitive potassium channels play an essential role in coupling glucose metabolism to the secretion of insulin. Although much of the literature is available on the antidiabetic effects of medicinal plants, very limited studies discuss their direct action on pancreatic KATP. The aim of this review is to focus on the modulatory effects of antidiabetic medicinal plants and their active constituents on pancreatic KATP. The KATP channel should be regarded as a key therapeutic milestone in the treatment of diabetes. Therefore, continuous research into the interaction of medicinal plants with the KATP channel is crucial.

Maturity-Onset Diabetes of the Young: Mutations, Physiological Consequences, and Treatment Options

Maturity-Onset Diabetes of the Young (MODY) is a rare form of diabetes which affects between 1% and 5% of diagnosed diabetes cases. Clinical characterizations of MODY include onset of diabetes at an early age (before the age of 30), autosomal dominant inheritance pattern, impaired glucose-induced secretion of insulin, and hyperglycemia. Presently, 14 MODY subtypes have been identified. Within these subtypes are several mutations which contribute to the different MODY phenotypes. Despite the identification of these 14 subtypes, MODY is often misdiagnosed as type 1 or type 2 diabetes mellitus due to an overlap in clinical features, high cost and limited availability of genetic testing, and unfamiliarity with MODY outside of the medical profession. The primary aim of this review is to investigate the genetic characterization of the MODY subtypes. Additionally, this review will elucidate the link between the genetics, function, and clinical manifestations of MODY in each of the 14 subtypes. In providing this knowledge, we hope to assist in the accurate diagnosis of MODY patients and, subsequently, in ensuring they receive appropriate treatment.

Role of Actionable Genes in Pursuing a True Approach of Precision Medicine in Monogenic Diabetes

Monogenic diabetes is a genetic disorder caused by one or more variations in a single gene. It encompasses a broad spectrum of heterogeneous conditions, including neonatal diabetes, maturity onset diabetes of the young (MODY) and syndromic diabetes, affecting 1-5% of patients with diabetes. Some of these variants are harbored by genes whose altered function can be tackled by specific actions ("actionable genes"). In suspected patients, molecular diagnosis allows the implementation of effective approaches of precision medicine so as to allow individual interventions aimed to prevent, mitigate or delay clinical outcomes. This review will almost exclusively concentrate on the clinical strategy that can be specifically pursued in carriers of mutations in "actionable genes", including ABCC8, KCNJ11, GCK, HNF1A, HNF4A, HNF1B, PPARG, GATA4 and GATA6. For each of them we will provide a short background on what is known about gene function and dysfunction. Then, we will discuss how the identification of their mutations in individuals with this form of diabetes, can be used in daily clinical practice to implement specific monitoring and treatments. We hope this article will help clinical diabetologists carefully consider who of their patients deserves timely genetic testing for monogenic diabetes.

In Vitro and In Vivo Antidiabetic Potential of Monoterpenoids: An Update

Diabetes mellitus (DM) is a chronic metabolic condition characterized by persistent hyperglycemia due to insufficient insulin levels or insulin resistance. Despite the availability of several oral and injectable hypoglycemic agents, their use is associated with a wide range of side effects. Monoterpenes are compounds extracted from different plants including herbs, vegetables, and fruits and they contribute to their aroma and flavor. Based on their chemical structure, monoterpenes are classified into acyclic, monocyclic, and bicyclic monoterpenes. They have been found to exhibit numerous biological and medicinal effects such as antipruritic, antioxidant, anti-inflammatory, and analgesic activities. Therefore, monoterpenes emerged as promising molecules that can be used therapeutically to treat a vast range of diseases. Additionally, monoterpenes were found to modulate enzymes and proteins that contribute to insulin resistance and other pathological events caused by DM. In this review, we highlight the different mechanisms by which monoterpenes can be used in the pharmacological intervention of DM via the alteration of certain enzymes, proteins, and pathways involved in the pathophysiology of DM. Based on the fact that monoterpenes have multiple mechanisms of action on different targets in in vitro and in vivo studies, they can be considered as lead compounds for developing effective hypoglycemic agents. Incorporating these compounds in clinical trials is needed to investigate their actions in diabetic patients in order to confirm their ability in controlling hyperglycemia.

Approach to the Patient with MODY-Monogenic Diabetes

Maturity-onset diabetes of the young, or MODY-monogenic diabetes, is a not-so-rare collection of inherited disorders of non-autoimmune diabetes mellitus that remains insufficiently diagnosed despite increasing awareness. These cases are important to efficiently and accurately diagnose, given the clinical implications of syndromic features, cost-effective treatment regimen, and the potential impact on multiple family members. Proper recognition of the clinical manifestations, family history, and cost-effective lab and genetic testing provide the diagnosis. All patients must undergo a thorough history, physical examination, multigenerational family history, lab evaluation (glycated hemoglobin A1c [HbA1c], glutamic acid decarboxylase antibodies [GADA], islet antigen 2 antibodies [IA-2A], and zinc transporter 8 [ZnT8] antibodies). The presence of clinical features with 3 (or more) negative antibodies may be indicative of MODY-monogenic diabetes, and is followed by genetic testing. Molecular genetic testing should be performed before attempting specific treatments in most cases. Additional testing that is helpful in determining the risk of MODY-monogenic diabetes is the MODY clinical risk calculator (>25% post-test probability in patients not treated with insulin within 6 months of diagnosis should trigger genetic testing) and 2-hour postprandial (after largest meal of day) urinary C-peptide to creatinine ratio (with a ≥0.2 nmol/mmol to distinguish HNF1A- or 4A-MODY from type 1 diabetes). Treatment, as well as monitoring for microvascular and macrovascular complications, is determined by the specific variant that is identified. In addition to the diagnostic approach, this article will highlight recent therapeutic advancements when patients no longer respond to first-line therapy (historically sulfonylurea treatment in many variants).

LEARNING OBJECTIVES

Upon completion of this educational activity, participants should be able to.

TARGET AUDIENCE

This continuing medical education activity should be of substantial interest to endocrinologists and all health care professionals who care for people with diabetes mellitus.

Treatment Options for MODY Patients: A Systematic Review of Literature

Maturity-onset diabetes of the young (MODY) is an unusual form of diabetes with specific features that distinguish it from type 1 and type 2 diabetes. There are 14 known subtypes of MODY, and mutations in three genes (HNF1A, HNF4A, GCK) account for about 95% of all MODY cases. Diagnosis usually occurs before the age of 25 years, although less frequent forms may occur more often-but not necessarily-later in life. The molecular diagnosis may tailor the choice of the most appropriate treatment, with the aim to optimize blood glucose control, reduce the risk of hypoglycemic events and long-term complications, and enable proper genetic counseling. Treatment is usually unnecessary for patients with mutations in the GCK gene, while oral hypoglycemic agents (generally sulphonylureas) are recommended for patients with mutations in the HNF4A and HNF1A genes. More recent data show that other glucose-lowering agents can be effective in the latter patients, and additional and alternative therapies have been proposed. Proper management guidelines during pregnancy have been developed for carriers of GCK gene mutations, but such guidelines are still a subject of debate in other cases, although some recommendations are available. The other subtypes of MODY are even more rare, and very little data are available in the literature. In this review we summarize the most pertinent findings and recommendations on the treatment of patients with the different subtypes of MODY. Our aim is to provide the reader with an easy-to-read update that can be used to drive the clinician's therapeutical approach to these patients after the molecular diagnosis.

Monogenic diabetes: the impact of making the right diagnosis

PURPOSE OF REVIEW

Monogenic forms of diabetes have received increased attention and genetic testing is more widely available; however, many patients are still misdiagnosed as having type 1 (T1D) or type 2 diabetes. This review will address updates to monogenic diabetes prevalence, identification, treatment, and genetic testing.

RECENT FINDINGS

The creation of a T1D genetic risk score and the use of noninvasive urinary C-peptide creatinine ratios have provided new tools to aid in the discrimination of possible monogenic diabetes from likely T1D. Early, high-dose sulfonylurea treatment in infants with a KCNJ11 or ABCC8 mutation continues to be well tolerated and effective. As the field moves towards more comprehensive genetic testing methods, there is an increased opportunity to identify novel genetic causes. Genetic testing results continue to allow for personalized treatment but should provide patient information at an appropriate health literacy level.

SUMMARY

Although there have been clinical and genetic advances in monogenic diabetes, patients are still misdiagnosed. Improved insurance coverage of genetic testing is needed. The majority of data on monogenic diabetes has been collected from Caucasian populations, therefore, research studies should endeavor to include broader ethnic and racial diversity to provide comprehensive information for all populations.

Genetic causes and treatment of neonatal diabetes and early childhood diabetes

Diabetes mellitus and impaired fasting glucose associated with single gene mutations are less rare than previously thought and may account for more than 6% of patients attending a pediatric diabetes clinic. The number of loci involved in monogenic diabetes exceed 25, and appropriate genetic diagnosis is crucial to direct therapy, for genetic counseling and for prognosis of short- and long-term complications. Among patients with neonatal diabetes (i.e. with onset within first 6 months of life) and patients with Maturity Onset Diabetes of the Young (MODY; an autosomal dominant form of diabetes), those carrying mutations in KCNJ11, ABCC8, HNF1A and HNF4A genes usually respond to oral therapy with sulphonylurea, while those bearing GCK mutations do not necessitate any treatment. Sensor-augmented continuous subcutaneous insulin infusion has been successfully employed in neonatal diabetes, and long-lasting effectiveness of sulfonylurea in KCNJ11 mutation carriers with neonatal diabetes well documented.

Monogenic Diabetes in Children and Adolescents: Recognition and Treatment Options

PURPOSE OF REVIEW

We provide a review of monogenic diabetes in young children and adolescents with a focus on recognition, management, and pharmacological treatment.

RECENT FINDINGS

Monogenic forms of diabetes account for approximately 1-2% of diabetes in children and adolescents, and its incidence has increased in recent years due to greater awareness and wider availability of genetic testing. Monogenic diabetes is due to single gene defects that primarily affect beta cell function with more than 30 different genes reported. Children with antibody-negative, C-peptide-positive diabetes should be evaluated and genetically tested for monogenic diabetes. Accurate genetic diagnosis impacts treatment in the most common types of monogenic diabetes, including the use of sulfonylureas in place of insulin or other glucose-lowering agents or discontinuing pharmacologic treatment altogether. Diagnosis of monogenic diabetes can significantly improve patient care by enabling prediction of the disease course and guiding appropriate management and treatment.

Fifteen-minute consultation: Monogenic forms of diabetes with onset after age 6 months

Monogenic forms of diabetes (historically known as Maturity Onset Diabetes of the Young (MODY)) are caused by single gene mutations inherited in an autosomal dominant fashion that result in reduced pancreatic beta cell function. Children with these forms of diabetes may be misdiagnosed as having type 1 or 2 diabetes, which has important implications for treatment, genetic counselling, screening of family members and prognosis. Useful tools now exist to aid in their diagnosis and management. Here, we attempt to outline the clinical features that will help the physician make the differentiation from other diabetes subtypes.

Use of oral antidiabetic drugs in the treatment of maturity-onset diabetes of the young: A mini review

MODY (maturity-onset diabetes of the young) is a genetically linked group of clinically heterogeneous subtypes of diabetes. Roughly 5% of people with diabetes mellitus diagnosed prior to age 45 have MODY diabetes. Most of them have been erroneously diagnosed as patients with either type 1 or type 2 diabetes and, as a result, have been improperly treated. Genetic identification of MODY diabetes and its subtypes allows proper treatment and enables clinicians to switch many patients to oral antidiabetic agents, mainly sulphonylureas. However, some new classes of oral antidiabetic drugs have also been tested and found to be effective in MODY patients. We have searched for research articles and case reports written in full-text English or with an English abstract, using the following keywords: MODY and oral antidiabetic* in the databases Cochrane Library, PubMed, and Science Direct. Therapeutic options using currently standardized oral antidiabetic drugs (mainly sulphonylureas), as well as more experimental treatment with other classes of oral antidiabetic drugs in different types of MODY, are discussed, with special focus on the therapy of the most common MODY subtypes, including specific conditions such as pregnancy. This review article summarizes the currently available information about oral antidiabetic treatment of patients with MODY diabetes.

Drugs for the treatment of pediatric type 2 diabetes mellitus and related co-morbidities

The continuing global epidemic of obesity in adolescents has raised the prevalence of type 2 diabetes mellitus (T2DM). Despite the wealth of information concerning T2DM in adults, rare data are available targeting treatment of T2DM in pediatric. Areas covered: This article has reviewed clinical practice guidelines, particularly the American Diabetes Association and the Pediatric Endocrine Society consensus, jointly with clinical trial data available in databases with respect to the use of available pharmacological options to treat T2DM and its complications in youth. Expert opinion: The use of other pharmacological treatments of T2DM in addition to metformin and insulin entails several problems. Since rare studies have been conducted on the medications available to manage T2DM in children, treating them may be more difficult than that of adults. It needs longer and larger size clinical trials along with better pharmacological agents to affect various pathophysiological mechanisms of diabetes. Meanwhile, the efficacy and safety of combinations therapies should be completed in preclinical and clinical phases.

Successful maintenance on sulphonylurea therapy and low diabetes complication rates in a HNF1A-MODY cohort

AIMS

HNF1A gene mutations are the most common cause of maturity-onset diabetes of the young (MODY) in the UK. Persons with HNF1A-MODY display sensitivity to sulphonylurea therapy; however, the long-term efficacy is not established. There is limited literature as to the prevalence of micro- and macrovascular complications in this unique cohort. The aim of this study was to determine the natural progression and clinical management of HNF1A-MODY diabetes in a dedicated MODY clinic.

METHODS

Sixty patients with HNF1A-MODY and a cohort of 60 BMI-, age-, ethnicity- and diabetes duration-matched patients with Type 1 diabetes mellitus participated in the study. All patients were phenotyped in detail. Clinical follow-up of the HNF1A-MODY cohort occurred on a bi-annual basis.

RESULTS

Following a genetic diagnosis of MODY, the majority of the cohort treated with sulphonylurea therapy remained insulin independent at 84-month follow-up (80%). The HbA1c in the HNF1A-MODY group treated with sulphonylurea therapy alone improved significantly over the study period [from 49 (44-63) mmol/mol, 6.6 (6.2-7.9)% to 41 (31-50) mmol/mol, 5.9 (5-6.7)%; P = 0.003]. The rate of retinopathy was significantly lower than that noted in the Type 1 diabetes mellitus group (13.6 vs. 50%; P = 0.0001).There was also a lower rate of microalbuminuria and cardiovascular disease in the HNF1A-MODY group compared with the Type 1 diabetes mellitus group.

CONCLUSIONS

This study demonstrates that the majority of patients with HNF1A-MODY can be maintained successfully on sulphonylurea therapy with good glycaemic control. We note a significantly lower rate of micro- and macrovascular complications than reported previously. The use of appropriate therapy at early stages of the disorder may decrease the incidence of complications.

Treatment of young patients with HNF1A mutations (HNF1A-MODY)

AIM

Children and adolescents with a molecular diagnosis of HNF1A-MODY should be treated with oral sulfonylurea according to current International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines.

METHODS

We surveyed the German-Austrian DPV database of 50 043 people and included 114 patients with a confirmed molecular-genetic diagnosis of HNF1A mutation and diabetes onset at below age 18 years. We analysed hypoglycaemic episodes, metabolic control (HbA1c ) and other clinical variables according to treatment groups.

RESULTS

People with HNF1A-MODY were included and analysed according to treatment with insulin alone (n = 34), sulfonylurea (n = 30), meglitinides (n = 22) or lifestyle (n = 28). In those receiving any drug treatment (n = 86), severe hypoglycaemia did not occur with meglitinide and was highest (at 3.6 events per 100 patient-years) with insulin. HbA1c was highest with insulin treatment (insulin = 58 mmol/mol, 7.5%; sulfonylurea = 55 mmol/mol, 7.2%; meglitinides = 52 mmol/mol, 6.9%; P = 0.008), whereas weight (BMI SD score), serum lipids and blood pressure were not different.

CONCLUSIONS

Of note, 40% of people with HNF1A-MODY and medical treatment were receiving insulin alone and thus were not being treated in line with up-to-date International Society for Pediatric and Adolescent Diabetes/International Diabetes Federation guidelines, despite insulin treatment being associated with worse metabolic control and the risk of hypoglycaemia. The unlicensed use of oral drugs in patients below age 18 years and adherence by both doctors and patients to the initial insulin treatment might contribute to this finding.

A review of the treatment of type 2 diabetes in children

The incidence of type 2 diabetes and obesity in children and adolescents has risen at staggering rates. Studies have shown that treating type 2 diabetes with oral medications in children may be more difficult than treating in adults. Compounding this problem is the fact that most of the medications available for treating type 2 diabetes have not been studied in children. Recently, the American Diabetes Association and the Pediatric Endocrine Society have collaborated to create a guideline for the treatment of type 2 diabetes in children. Similar to the treatment of adults with type 2 diabetes, metformin remains the mainstay of therapy along with diet and exercise. Adjunctive therapy should be based on the limited clinical evidence available as well as on patient preference. In order to avoid detrimental microvascular and macrovascular complications, patients, clinicians, and family members should work together to ensure adequate treatment of type 2 diabetes in children.