Successful off-label sulfonylurea treatment of neonatal diabetes mellitus due to chromosome 6 abnormalities

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.

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.

Promising therapeutic aspects in human genetic imprinting disorders

Genomic imprinting is an epigenetic phenomenon of monoallelic gene expression pattern depending on parental origin. In humans, congenital imprinting disruptions resulting from genetic or epigenetic mechanisms can cause a group of diseases known as genetic imprinting disorders (IDs). Genetic IDs involve several distinct syndromes sharing homologies in terms of genetic etiologies and phenotypic features. However, the molecular pathogenesis of genetic IDs is complex and remains largely uncharacterized, resulting in a lack of effective therapeutic approaches for patients. In this review, we begin with an overview of the genomic and epigenomic molecular basis of human genetic IDs. Notably, we address ethical aspects as a priority of employing emerging techniques for therapeutic applications in human IDs. With a particular focus, we delineate the current field of emerging therapeutics for genetic IDs. We briefly summarize novel symptomatic drugs and highlight the key milestones of new techniques and therapeutic programs as they stand today which can offer highly promising disease-modifying interventions for genetic IDs accompanied by various challenges.

Growth and development in monogenic forms of neonatal diabetes

PURPOSE OF REVIEW

Neonatal diabetes mellitus (NDM) is a rare disorder in which 80-85% of infants diagnosed under 6 months of age will be found to have an underlying monogenic cause. This review will summarize what is known about growth and neurodevelopmental difficulties among individuals with various forms of NDM.

RECENT FINDINGS

Patients with NDM often have intrauterine growth restriction and/or low birth weight because of insulin deficiency in utero and the severity and likelihood of ongoing growth concerns after birth depends on the specific cause. A growing list of rare recessive causes of NDM are associated with neurodevelopmental and/or growth problems that can either be related to direct gene effects on brain development, or may be related to a variety of co-morbidities. The most common form of NDM results in spectrum of neurological disability due to expression of mutated KATP channels throughout the brain.

SUMMARY

Monogenic causes of neonatal diabetes are characterized by variable degree of restriction of growth in utero because of deficiency of insulin that depends on the specific gene cause. Many forms also include a spectrum of neurodevelopmental disability because of mutation-related effects on brain development. Longer term study is needed to clarify longitudinal effects on growth into adulthood.

Clinical characteristics, growth patterns, and long-term diabetes complications of 24 patients with neonatal diabetes mellitus: A single center experience

OBJECTIVES

Neonatal diabetes mellitus (NDM) is a rare form of monogenic diabetes, diagnosed before age 6 months. We aimed to describe the clinical characteristics, molecular genetics, and long-term follow-up of NDM patients from a single pediatric endocrine center in Israel.

METHODS

Retrospective study (1975-2020) of all patients diagnosed with diabetes before 6 months of age, who tested negative for pancreatic autoantibodies. Medical records were reviewed for demographic, familial and medical history, and clinical and biochemical features; a genetic analysis was performed.

RESULTS

Of 24 patients, nine had transient neonatal diabetes (TNDM) and 15 permanent neonatal diabetes (PNDM), of whom five had rare syndromic causes. Genetic etiology was revealed in 87.5% of the NDM cohort, and the most common causes were ABCC8 mutations in TNDM and KCNJ11 and insulin gene mutations in PNDM. The switch from insulin to off-label sulfonylurea therapy was successful for 5/9 (56%) of the qualifying candidates. Severe hypoglycemia and diabetic ketoacidosis developed in 2 (8%) patients, and chronic diabetes complications in 5 (21%) patients with more than 10 years NDM. At last follow-up, weight and height of all but two syndromic PNDM patients were normal. The median height-SDS of the TNDM subgroup was significantly taller and the mean weight-SDS significantly heavier than those of the PNDM subgroup (-0.52 (-0.67, -0.09) vs. -0.9 (-1.42, -0.3) (p = 0.035) and 0.22 ± 0.69 vs. -0.89 ± 1.21 (p = 0.02), respectively). PNDM patients showed no incremental change in mean weight SDS over the time.

CONCLUSION

The Israeli NDM cohort has clinical and genetic characteristics comparable with other populations. Patients with TNDM were taller and heavier than those diagnosed with PNDM, although both show rapid catch-up growth and reached normal growth parameters. Chronic diabetes complications developed in patients with long-standing NDM.

Clinical features and partial proportional molecular genetics in neonatal diabetes mellitus: a retrospective analysis in southwestern China

PURPOSE

To explore the relationship of phenotype and genotype of neonatal diabetes mellitus (NDM) in southwestern China.

METHODS

Sixteen cases of NDM admitted to Children's Hospital of Chongqing Medical University from May 2009 to May 2019 were included in this study. The clinical features of the included infants were retrospectively analyzed. Peripheral blood samples of the patients and their parents were collected for mutation detection.

RESULTS

Among the 16 cases of NDM, 8 cases were permanent neonatal diabetes mellitus (PNDM) (including 3 clinical syndromes), and 3 cases were transient neonatal diabetes mellitus (TNDM). Mutation detection was performed in six cases. The mutation genes and their loci were FOXP3 p.V408M, KCNJ11 p.C166Y, ABCC8 p.S830P, KCNJ11 p.I182T, KCNJ11 p.G334D, and ZFP57 p.R125X,412. ABCC8 p.S830P was the new found pathogenic site of gene mutation. According to the clinical features and follow-up results, one case was diagnosed as IPEX syndrome, two as DEND syndrome, two as simple PNDM, and one as TNDM. All the TNDM could spontaneously alleviate and then insulin was withdrawn. In PNDM, 75% of those with KATP channel gene mutation could be completely or partially converted to oral sulfonylureas treatment, however, the rest cases needed lifelong insulin replacement therapy.

CONCLUSION

The clinical manifestations and treatment regimens of patients with NDM vary according to the type of gene mutation. Even the same mutant genotype has differences in phenotype and response to treatment.

Long-term Metabolic and Socioeducational Outcomes of Transient Neonatal Diabetes: A Longitudinal and Cross-sectional Study

OBJECTIVE

Transient neonatal diabetes mellitus (TNDM) occurs during the 1st year of life and remits during childhood. We investigated glucose metabolism and socioeducational outcomes in adults.

RESEARCH DESIGN AND METHODS

We included 27 participants with a history of TNDM currently with (n = 24) or without (n = 3) relapse of diabetes and 16 non-TNDM relatives known to be carriers of causal genetic defects and currently with (n = 9) or without (n = 7) diabetes. Insulin sensitivity and secretion were assessed by hyperinsulinemic-euglycemic clamp and arginine-stimulation testing in a subset of 8 TNDM participants and 7 relatives carrying genetic abnormalities, with and without diabetes, compared with 17 unrelated control subjects without diabetes.

RESULTS

In TNDM participants, age at relapse correlated positively with age at puberty (P = 0.019). The mean insulin secretion rate and acute insulin response to arginine were significantly lower in TNDM participants and relatives of participants with diabetes than in control subjects (median 4.7 [interquartile range 3.7-5.7] vs. 13.4 [11.8-16.1] pmol/kg/min, P < 0.0001; and 84.4 [33.0-178.8] vs. 399.6 [222.9-514.9] µIU/mL, P = 0.0011), but were not different between participants without diabetes (12.7 [10.4-14.3] pmol/kg/min and 396.3 [303.3-559.3] µIU/mL, respectively) and control subjects. Socioeducational attainment was lower in TNDM participants than in the general population, regardless of diabetes duration.

CONCLUSIONS

Relapse of diabetes occurred earlier in TNDM participants compared with relatives and was associated with puberty. Both groups had decreased educational attainment, and those with diabetes had lower insulin secretion capacity; however, there was no difference in insulin resistance in adulthood. These forms of diabetes should be included in maturity-onset diabetes of the young testing panels, and relatives of TNDM patients should be screened for underlying defects, as they may be treated with drugs other than insulin.

Diagnosis and management of neonatal diabetes mellitus: A survey of physicians' perceptions and practices in ASPED countries

AIM

To ascertain the awareness and practice of neonatal diabetes mellitus (NDM) among paediatricians in Arab countries.

METHODS

An online questionnaire was distributed to physicians associated with the Arab Society for Paediatric Endocrinology and Diabetes (ASPED).

RESULTS

We received 126 replies, from 16 countries. All except one classified the survey's case scenario as NDM and 94% agreed that NDM patients should have detailed assessment to identify extra-pancreatic features. Although 92% felt that genetic testing is necessary, only 72% requesting them routinely and 32% unaware of the availability of free genetic testing. Insulin is considered the initial therapy for 93% and 80% diluted insulin to deliver accurate doses. Basal-bolus regimen was preferred by 36% and similar percentage used insulin pump. The remaining 28% favour long acting insulin alone. Oral sulfonylureas would be tried empirically by 34% and 69% would do so if genetic testing is unavailable. Whilst 70% have no local NDM management guidelines, 41% are unaware of any international guidelines.

CONCLUSIONS

The ASPED surveyed clinicians have good awareness of NDM diagnosis with marked variation in their practice raising the need to establish management guideline for the condition. The survey highlights areas to focus on in developing consensus and educational activities.

Uncommon Presentations of Diabetes: Zebras in the Herd

The majority of patients with diabetes are diagnosed as having either type 1 or type 2 diabetes. However, when encountered in clinical practice, some patients may not match the classic diagnostic criteria or expected clinical presentation for either type of the disease. Latent autoimmune, ketosis-prone, and monogenic diabetes are nonclassical forms of diabetes that are often misdiagnosed as either type 1 or type 2 diabetes. Recognizing the distinguishing clinical characteristics and understanding the diagnostic criteria for each will lead to appropriate treatment, facilitate personalized medicine, and improve patient outcomes.

Neonatal Diabetes Mellitus

Neonatal Diabetes (ND) mellitus is a rare genetic disease (1 in 90,000 live births). It is defined by the presence of severe hyperglycaemia associated with insufficient or no circulating insulin, occurring mainly before 6 months of age and rarely between 6 months and 1 year. Such hyperglycaemia requires either transient treatment with insulin in about half of cases, or permanent insulin treatment. The disease is explained by two major groups of mechanism: malformation of the pancreas with altered insulin-secreting cells development/survival or abnormal function of the existing pancreatic β cell. The most frequent genetic causes of neonatal diabetes mellitus with abnormal β cell function are abnormalities of the 6q24 locus and mutations of the ABCC8 or KCNJ11 genes coding for the potassium channel in the pancreatic β cell. Other genes are associated with pancreas malformation or insufficient β cells development or destruction of β cells. Clinically, compared to patients with an ABCC8 or KCNJ11 mutation, patients with a 6q24 abnormality have lower birth weight and height, are younger at diagnosis and remission, and have a higher malformation frequency. Patients with an ABCC8 or KCNJ11 mutation have neurological and neuropsychological disorders in all those tested carefully. Up to 86% of patients who go into remission have recurrent diabetes when they reach puberty, with no difference due to the genetic origin. All these results reinforce the importance of prolonged follow-up by a multidisciplinary pediatric team, and later doctors specializing in adult medicine. 90% of the patients with an ABCC8 or KCNJ11 mutation as well as those with 6q24 anomalies are amenable to a successful switch from insulin injection to oral sulfonylureas.

Pediatric Monogenic Diabetes: A Unique Challenge and Opportunity

Monogenic diabetes affects approximately 120,000 people in the United States but continues to be misdiagnosed. Within the pediatric population, 1% to 3% of diabetes is monogenic, and early diagnosis and genetically targeted management of congenital diabetes and maturity onset diabetes of the young (MODY) can have a tremendous impact on future health outcomes and quality of life. In some of the more common monogenic diabetes types, patients can switch from insulin therapy to sulfonylureas or even discontinue glucose-lowering therapy with stable glycemic control. Advancements in the field have identified tools and resources to aid in distinguishing patients likely to have monogenic diabetes from the more common forms of type 1 and type 2 diabetes. However, genetic testing with accurate interpretation of results is necessary to confirm a diagnosis and direct treatment selection and disease management. This article discusses challenges and opportunities in monogenic diabetes in the pediatric population. [Pediatr Ann. 2019;48(8):e319-e325.].

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.

Congenital Diabetes: Comprehensive Genetic Testing Allows for Improved Diagnosis and Treatment of Diabetes and Other Associated Features

PURPOSE OF REVIEW

The goal of this review is to provide updates on congenital (neonatal) diabetes from 2011 to present, with an emphasis on publications from 2015 to present.

RECENT FINDINGS

There has been continued worldwide progress in uncovering the genetic causes of diabetes presenting within the first year of life, including the recognition of nine new causes since 2011. Management has continued to be refined based on underlying molecular cause, and longer-term experience has provided better understanding of the effectiveness, safety, and sustainability of treatment. Associated conditions have been further clarified, such as neurodevelopmental delays and pancreatic insufficiency, including a better appreciation for how these "secondary" conditions impact quality of life for patients and their families. While continued research is essential to understand all forms of congenital diabetes, these cases remain a compelling example of personalized genetic medicine.