High prevalence of severe circulatory complications with diazoxide in premature infants

Pulmonary Hypertension and Necrotizing Enterocolitis in Neonates Treated with Diazoxide

OBJECTIVE

This study aimed to evaluate the prevalence of adverse outcomes, specifically pulmonary hypertension (PH) and suspected or confirmed necrotizing enterocolitis (NEC), and their associated risk factors, in neonates treated with diazoxide.

STUDY DESIGN

A retrospective study in infants born ≥ 316/7 weeks and admitted between January 2014 and June 2020. Combined adverse outcomes possibly associated to diazoxide were PH (systolic pulmonary pressure of ≥40 mm Hg or an eccentricity index ≥1.3) and suspected or confirmed NEC (suspected: stop feeds and antibiotics and confirmed: modified Bell stage ≥2). Echocardiography data extractors were masked to infants' characteristics.

RESULTS

A total of 63 infants were included; 7 (11%) with suspected and 1 (2%) with confirmed NEC. Of the 36 infants with an available echocardiography after initiation of diazoxide treatment, 12 (33%) had PH. All infants with suspected or confirmed NEC were males (p = 0.01), whereas PH occurred mostly in females (75%, p = 0.02). The combined adverse outcome occurred in 14/26 (54%) infants exposed to >10 mg/kg/day, compared to 6/37 (16%) exposed to ≤10 mg/kg/day (p = 0.006). This association remained significant after adjustment for sex, small for gestational age status, and gestational age at birth (odds ratio: 6.1, 95% confidence interval: 1.7-21.7, p = 0.005). Left ventricular dysfunction was found in 19 infants (30%) but was not discriminative for the combined outcome.

CONCLUSION

PH and suspected or confirmed NEC were identified frequently in neonates treated with diazoxide. A total dose >10 mg/kg/day was associated with an increased occurrence of these complications.

KEY POINTS

· PH and suspected or confirmed NEC were frequently found in neonates treated with diazoxide.. · A total dose >10 mg/kg/day was associated with an increased occurrence of these complications.. · Echocardiography screening should be considered in neonates exposed to diazoxide..

Delayed-Onset Transient Hyperinsulinism in Infants with Very Low and Extremely Low Birth Weights: A Cohort Study

We describe 16 infants born preterm with birth weights <1500 g and transient hyperinsulinism. The onset of hyperinsulinism was delayed and often coincident with clinical stabilization. We hypothesize that postnatal stress caused by prematurity and associated problems may contribute to development of delayed-onset transient hyperinsulinism.

Diazoxide for Neonatal Hyperinsulinemic Hypoglycemia and Pulmonary Hypertension

Hypoglycemia in neonates is associated with long-term neurodevelopmental effects. Hyperinsulinemic hypoglycemia (HH) is the most common cause of persistent hypoglycemia in neonatal intensive care units. Diazoxide is the only medication that is currently recommended for treatment of HH in neonates. However, the use of diazoxide in neonates is associated with pulmonary hypertension as an adverse effect. In this article, we review the literature on the mechanism of action and adverse effects with the use of diazoxide in neonatal hyperinsulinism. We then present a case series of neonates treated with diazoxide in our neonatal intensive care unit over a 5-year period. Among 23 neonates who received diazoxide, 4 developed pulmonary hypertension and 1 died. All infants who developed pulmonary hypertension were born preterm at less than 36 weeks gestation and had pre-existing risk factors for pulmonary hypertension. HH in preterm neonates, with pre-existing pulmonary hypertension or with risk factors for pulmonary hypertension requires thoughtful management.

The danger of diazoxide in the neonatal intensive care unit

Background

The most common cause of persistent hypoglycemia in infancy is hyperinsulinemic hypoglycemia. When conservative measures fail, providers often use medications to treat persistent hypoglycemia. Diazoxide is first-line therapy for neonatal hypoglycemia and works by inhibiting insulin secretion. Diazoxide is associated with fluid retention, and less commonly with respiratory decompensation and pulmonary hypertension. Case reports documenting these severe adverse events exist in the literature, although the overall incidence, risk factors, and timing for these effects in a newborn are not clearly defined.

Methods

We performed a retrospective chart review of all infants admitted to the neonatal intensive care unit (NICU) at Regional One Health from 1 January 2013 until 15 August 2019, who received diazoxide as a treatment for persistent hypoglycemia secondary to hyperinsulinism. Patients were stratified as either having no adverse event or having an adverse outcome to the medication. A severe adverse outcome was defined as any known major side effect of the medication, which a patient developed within 2 weeks of medication initiation that led to medication discontinuation.

Results

From our pharmacy database, we identified a total of 15 babies who received diazoxide for persistent hypoglycemia. Of these patients, eight (53%) were classified as having a complication requiring discontinuation of the medication. Six out of eight patients required intubation with mechanical ventilation and five out of eight patients developed pulmonary hypertension. All patients returned to their baseline respiratory support after drug discontinuation.

Conclusions

A total of 53% of our study population had an adverse outcome to diazoxide. Previous studies suggest 5% of patients may have respiratory decompensation and require ventilatory support while on diazoxide; however, 40% of our patients deteriorated and then required mechanical ventilation. Based on our data, respiratory deterioration may be more likely to occur when diazoxide is used in preterm infants, those with lower birth weight and intrauterine growth restriction.

Plain language summary

The dangers in diazoxide Newborns could experience a transient period of low blood glucose levels soon after birth. However, some may progress to persistent low blood glucose levels that cannot be controlled with adequate glucose infusion and may require other ways of treatment. Diazoxide is the first-line drug approved by the US Food and Drug Administration (FDA) for this condition. However, certain cases have reported the development of respiratory deterioration, including increased blood pressure in lung circulation after its use. This prompted a black box warning in 2015 by the FDA. The incidence of neonatal low blood glucose levels seems to have increased and so has the use of this drug. Our study identifies 15 newborns who received diazoxide at Regional One Health neonatal intensive care unit in the past 6 years and reports a significantly higher rate of adverse events in our population leading to drug discontinuation in almost 53% of our cases.

Higher C-peptide levels and glucose requirements may identify neonates with transient hyperinsulinism hypoglycemia who will benefit from diazoxide treatment

The aim of the study was to characterize factors that may serve as clinical tools to identify neonates with transient neonatal hyperinsulinism hypoglycemia (HH) who may benefit from diazoxide treatment. This retrospective study included 141 neonates with transient HH (93 males) of whom 34 (24%) were treated with diazoxide. Diazoxide treatment was started at median age of 13 days (range 5-35) and discontinued at median age of 42 days (range 14-224). The maximal dose was 7.1 ± 2.3 mg/kg/day. Diazoxide-treated neonates required a higher glucose infusion rate (GIR) compared with non-treated neonates (16.6 ± 3.4 vs. 10.4 ± 4.0 mg/kg/min, respectively, P < .01), had a longer duration of intravenous fluids (15.9 ± 9.3 vs. 7.8 ± 6.5 days, P < .01), a longer hospitalization (32.8 ± 22.7 vs. 20.4 ± 13.4 days, P < .01), a longer duration of carbohydrate supplementation (38.9 ± 40.4 vs. 17.8 ± 21.4 days, P < .01), and higher mean C-peptide levels on "critical sample" (1.4 ± 0.9 vs. 0.8 ± 0.5 ng/ml, P < .01). Their insulin levels also tended to be higher (3.5 ± 2.9 vs. 2.2 ± 3.8 μU/ml, P = .07). A stepwise logistic regression model revealed that significant predictors of prolonged HH were maximal GIRs (odds ratio (OR) 1.56, 95%; confidence interval (CI) 1.3-1.88, P < .001) and C-peptide levels (OR 3.57, 95%; CI 1.3-12.1, P = .005).Conclusion: Higher C-peptide levels and higher GIR requirements may serve as clinical tools to identify neonates with transient HH who may benefit from diazoxide treatment.What is Known:• Neonates with transient hyperinsulinism usually do not require treatment beyond glucose supplementation due to its self-limited clinical course, but some may benefit from diazoxide treatment.What is New:• Higher C-peptide levels and higher GIR requirements may serve as clinical tools to identify neonates with transient HH who may benefit from diazoxide treatment.• The incidence of prolonged neonatal HH is higher than the currently accepted figures.

Transcutaneous blood gas monitoring among neonatal intensive care units in Japan

BACKGROUND

This study aimed to investigate the utility of transcutaneous (tc) measurements of partial pressure of oxygen (tcPO₂ ) and carbon dioxide (tcPCO₂ ) monitoring in neonatal intensive care units (NICUs) in Japan.

METHODS

At the end of 2016,we sent a survey questionnaire on tc monitoring to all 106 NICUs registered with the Japanese Neonatologist Association. The questions included usage, subjects, methods, management, and the practical usefulness of tc monitoring.

RESULTS

The questionnaire was returned by 69 NICUs (65.1% of response rate). Seventeen institutions (24.6%) measured both tcPCO₂ and tcPO₂ , and 42 (60.9%) measured tcPCO₂ alone. Transcutaneous PCO₂ or tcPO₂ monitoring was applied for "pre-viable" infants born at 22-23 weeks' gestational age (18.6% vs 23.5%), and infants of <500 g birthweight (30.5% vs 17.6%). The tcPCO₂ and tcPO₂ monitoring was started at birth in 49.2% and 70.6% of the newborn infants, respectively. The temperature of the sensor was set at <38°C for tcPCO₂ in 54.3% and >42°C for tcPO₂ in 58.9% of NICUs. The accuracy for tcPO₂ was rated as good in 35.3% or moderate in 64.7%, of institutions but or for tcPCO₂ as 1.7% or 93.2%of institutions , respectively.

CONCLUSION

Transcutaneous monitoring was widely, but limitedly, used for preterm infants. The lower temperature of the tcPCO₂ sensor compared to that reported in other developed countries might compromise the accuracy but increase the feasibility of tc monitoring in Japan.

Diazoxide-induced pulmonary hypertension in hyperinsulinaemic hypoglycaemia: Recommendations from a multicentre study in the United Kingdom

OBJECTIVE

Diazoxide is first-line treatment for hyperinsulinaemic hypoglycaemia (HH) but diazoxide-induced pulmonary hypertension (PH) can occur. We aim to characterize the incidence and risk factors of diazoxide-induced PH in a large HH cohort to provide recommendations for anticipating and preventing PH in diazoxide-treated patients with HH.

DESIGN AND PATIENTS

Retrospective cohort study involving four UK regional HH centres; review of case notes of HH patients on diazoxide.

MEASUREMENTS

The diagnosis of PH was based on clinical and echocardiography evidence. Patient and treatment-related risk factors were analysed for association.

RESULTS

Thirteen (6 men) of 177 HH diazoxide-treated patients developed PH, an incidence of 7%. In the PH group, HH was diagnosed at median (range) of 9 (1,180) days, with diazoxide commenced 4 (0,76) days from diagnosis and reaching a maximum dose of 7 (2.5,20) mg/kg/d. The majority (8 of 13 patients) developed PH within 2 weeks of diazoxide. Complete diazoxide withdrawal, but not dose reduction, led to PH resolution at 41 (3,959) days. In three patients, PH continued beyond 12 months. Risk factors for the development of PH included the presence of congenital heart disease (CHD) (P = .008), and total fluid volume exceeding 130 mL/kg/d in the immediate 24 hours preceding diazoxide (P = .019).

CONCLUSION

Pulmonary hypertension can occur in 7% of diazoxide-treated HH patients. Risk factors include the presence of congenital heart disease and fluid overload. Recommendations include echocardiography and fluid restriction to 130 mL/kg/d prior to diazoxide treatment and immediate discontinuation of diazoxide if PH develops.

Understanding the pathobiology in patent ductus arteriosus in prematurity-beyond prostaglandins and oxygen

The ductus arteriosus (DA) is probably the most intriguing vessel in postnatal hemodynamic transition. DA patency in utero is an active state, in which prostaglandin E₂ (PGE₂) and nitric monoxide (NO), play an important role. Since the DA gets programmed for postnatal closure as gestation advances, in preterm infants the DA frequently remains patent (PDA). PGE₂ exposure programs functional postnatal closure by inducing gene expression of ion channels and phosphodiesterases and anatomical closure by inducing intimal thickening. Postnatally, oxygen inhibits potassium and activates calcium channels, which ultimately leads to a rise in intracellular calcium concentration consequently inducing phosphorylation of the myosin light chain and thereby vasoconstriction of the DA. Since ion channel expression is lower in preterm infants, oxygen induced functional vasoconstriction is attenuated in comparison with full term newborns. Furthermore, the preterm DA is more sensitive to both PGE₂ and NO compared to the term DA pushing the balance toward less constriction. In this review we explain the physiology of DA patency in utero and subsequent postnatal functional closure. We will focus on the pathobiology of PDA in preterm infants and the (un)intended effect of antenatal exposure to medication on both fetal and neonatal DA vascular tone.

Prevalence of Adverse Events in Children With Congenital Hyperinsulinism Treated With Diazoxide

CONTEXT

Diazoxide, the only U.S. Food and Drug Administration-approved drug to treat hyperinsulinemic hypoglycemia, has been associated with several adverse events, which has raised concerns about the safety of this drug. Existing reports are limited to small studies and case reports.

OBJECTIVE

To determine prevalence of and clinical factors associated with adverse events in infants and children treated with diazoxide.

DESIGN

Retrospective cohort study of children with hyperinsulinism (HI) treated with diazoxide between 2003 and 2014.

SETTING

The Congenital Hyperinsulinism Center at the Children's Hospital of Philadelphia.

PATIENTS

Children and infants with laboratory-confirmed diagnosis of HI.

MAIN OUTCOME MEASURES

Prevalence of pulmonary hypertension (PH), edema, neutropenia, thrombocytopenia, and hyperuricemia was determined. Tests of association and logistic regression were used to identify potential risk factors.

RESULTS

A total of 295 patients (129 female) met inclusion criteria. The median age at diazoxide initiation was 29 days (interquartile range, 10 to 142 days; n = 226 available start dates); 2.4% of patients were diagnosed with PH after diazoxide initiation. Children with PH (P = 0.003) or edema (P = 0.002) were born at earlier gestational age and more frequently had potential PH risk factors, including respiratory failure and structural heart disease (P < 0.0001 and P = 0.005). Other adverse events included neutropenia (15.6%), thrombocytopenia (4.7%), and hyperuricemia (5.0%).

CONCLUSION

In this large cohort, PH occurred in infants with underlying risk factors, but no identifiable risk profile emerged for other adverse events. The relatively high prevalence of neutropenia, thrombocytopenia, and hyperuricemia suggests the value in proactively screening for these side effects in children treated with diazoxide.

Prevalence and safety of diazoxide in the neonatal intensive care unit

OBJECTIVE

Diazoxide is used to treat infants with persistent hypoglycemia, but the prevalence of its use and adverse effects are not well described. We report demographic and clinical characteristics of infants treated with diazoxide in neonatal intensive care units (NICUs).

STUDY DESIGN

Retrospective cohort study of infants 24-41 weeks' gestation admitted to 392 NICUs from 1997-2016, comparing characteristics between hypoglycemic infants exposed/not exposed to diazoxide. For diazoxide courses > 1 day, we report percentages of infants starting diuretics and/or developing new ventilator/oxygen requirement during therapy.

RESULTS

Among 1,249,466 infants, 185,832 had hypoglycemia; 1066/185,832 (0.57%) received diazoxide. Diazoxide use increased over time (P = 0.001). Infants receiving diazoxide varied from 0-14.9% among centers. New diuretic courses were associated with 91/664 (14%), and new oxygen or ventilator requirement during therapy was associated with 64/556 (12%) and 34/647 (5%), respectively.

CONCLUSIONS

Diazoxide use in NICU settings has increased over time. Infants receiving diazoxide commonly received diuretics.

Diagnosis and management of hyperinsulinaemic hypoglycaemia

Hyperinsulinaemic hypoglycaemia (HH) is a heterogeneous condition with dysregulated insulin secretion which persists in the presence of low blood glucose levels. It is the most common cause of severe and persistent hypoglycaemia in neonates and children. Recent advances in genetics have linked congenital HH to mutations in 14 different genes that play a key role in regulating insulin secretion (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, UCP2, HNF4A, HNF1A, HK1, PGM1, PPM2, CACNA1D, FOXA2). Histologically, congenital HH can be divided into 3 types: diffuse, focal and atypical. Due to the biochemical basis of this condition, it is essential to diagnose and treat HH promptly in order to avoid the irreversible hypoglycaemic brain damage. Recent advances in the field of HH include new rapid molecular genetic testing, novel imaging methods (18F-DOPA PET/CT), novel medical therapy (long-acting octreotide formulations, mTOR inhibitors, GLP-1 receptor antagonists) and surgical approach (laparoscopic surgery). The review article summarizes the current diagnostic methods and management strategies for HH in children.

Intracranial hemorrhage associated with medulla oblongata dysplasia in a premature infant: A case report

RATIONALE

Medulla oblongata dysplasia is an extremely rare form of neurodevelopmental immaturity in premature infants. Intracranial hemorrhage in premature infants may be closely related to neurodevelopmental immaturity.

DIAGNOSES

We report a female premature infant who succumbed to intracranial hemorrhage caused by medulla oblongata dysplasia.

PATIENT CONCERNS

The infant was born at 31 weeks gestation. The onset manifestation was symptomatic epilepsy associated with subependymal hemorrhage.

INTERVENTIONS

Levetiracetam and sodium valproate were administered. During the hospitalization, hydrocephalus developed and the intracranial hemorrhage aggravated.

OUTCOMES

The infant died on day 171 after birth.

LESSONS

Early identification and prompt treatment should be emphasized. Clinicians should be aware of this condition, as it can potentially cause neonatal intracranial hemorrhage.

Dilatation of the ductus arteriosus by diazoxide in fetal and neonatal rats

BACKGROUND

Diazoxide, an ATP-sensitive potassium channel opener, is the main therapeutic agent for treating hyperinsulinemic hypoglycemia. The aim of this study was to determine the in vivo ductus arteriosus (DA)-dilating effects of diazoxide in fetal and neonatal rats.

METHODS

Near-term rat pups delivered via cesarean section were housed at 33°C. After rapid whole-body freezing, the ductus arteriosus (DA) diameter was measured using a microscope and a micrometer. Full-term pregnant rats (gestational day 21) were injected i.p. with diazoxide (10 and 100 mg/kg) 4 h before delivery, and the neonatal DA diameter was measured at 0, 30, or 60 min after birth. The newborn rats were also injected i.p. with diazoxide (10 and 100 mg/kg) at birth or 60 min after birth. DA was measured at 0, 30, or 60 min after injection. In the fetal investigation, the effect of diazoxide was studied via simultaneous application of indomethacin (10 mg/kg) and L-nitroarginine methyl ester (L-NAME) on gestational days 21 and 19.

RESULTS

The control rats had rapid postnatal DA constriction (diameter, 0.80 and 0.08 mm at 0 and 60 min after birth, respectively). Diazoxide had a dose-dependent inhibitory effect on postnatal DA constriction. Prenatal diazoxide (10 mg/kg) inhibited postnatal DA closure (0.20 mm at 60 min after birth). The diazoxide injection (10 mg) at birth inhibited postnatal DA closure (0.14 mm at 60 min after birth). Diazoxide injection in 60-min-old rats dilated the constricted DA at 60 min (0.10 mm vs. 0.02 mm in the controls). In the fetal investigation, diazoxide inhibited the fetal DA constrictive effect of indomethacin and L-NAME.

CONCLUSION

Diazoxide attenuates postnatal DA constriction and dilates a closing DA in fetal and neonatal rats.

Clinical practice guidelines for congenital hyperinsulinism

Congenital hyperinsulinism is a rare condition, and following recent advances in diagnosis and treatment, it was considered necessary to formulate evidence-based clinical practice guidelines reflecting the most recent progress, to guide the practice of neonatologists, pediatric endocrinologists, general pediatricians, and pediatric surgeons. These guidelines cover a range of aspects, including general features of congenital hyperinsulinism, diagnostic criteria and tools for diagnosis, first- and second-line medical treatment, criteria for and details of surgical treatment, and future perspectives. These guidelines were generated as a collaborative effort between The Japanese Society for Pediatric Endocrinology and The Japanese Society of Pediatric Surgeons, and followed the official procedures of guideline generation to identify important clinical questions, perform a systematic literature review (April 2016), assess the evidence level of each paper, formulate the guidelines, and obtain public comments.

Experience of Octreotide Therapy for Hyperinsulinemic Hypoglycemia in Neonates Born Small for Gestational Age: A Case Series

AIMS

Hyperinsulinemic hypoglycemia (HH) is common in small-for-gestational-age (SGA) neonates. Diazoxide is often used as the first-line medication for HH in SGA neonates. Unfortunately, diazoxide is not authorized in China. We examined the effectiveness of octreotide as an alternative therapy to treat HH in SGA neonates. There is limited data on the use of octreotide in HH of SGA neonates.

METHODS

Seven SGA neonates with HH who were admitted to the Department of Neonatology at the Third Affiliated Hospital of Sun Yat-sen University between January 2013 and December 2014 received octreotide at an initial dose of 5 μg/kg/day through subcutaneous injection at 8-hour intervals. Depending on the glycemic control, the dose of octreotide was increased in increments of 2-5 μg/kg/day every 3-5 days to the maximum dose of 30 μg/kg/day.

RESULTS

The age of neonates with HH diagnosis ranged from 1 to 4 days. The maximum dose of octreotide ranged from 8 to 18 μg/kg/day. The duration of octreotide therapy ranged from 9 to 45 days. All patients had a clear glycemic response to octreotide, and no major adverse events were observed during the treatment.

CONCLUSIONS

Octreotide may be a useful alternative therapy in HH of SGA neonates when diazoxide is unavailable.

Perspective on the Genetics and Diagnosis of Congenital Hyperinsulinism Disorders

CONTEXT

Congenital hyperinsulinism (HI) is the most common cause of hypoglycemia in children. The risk of permanent brain injury in infants with HI continues to be as high as 25-50% due to delays in diagnosis and inadequate treatment. Congenital HI has been described since the birth of the JCEM under various terms, including "idiopathic hypoglycemia of infancy," "leucine-sensitive hypoglycemia," or "nesidioblastosis."

EVIDENCE ACQUISITION

In the past 20 years, it has become apparent that HI is caused by genetic defects in the pathways that regulate pancreatic β-cell insulin secretion.

EVIDENCE SYNTHESIS

There are now 11 genes associated with monogenic forms of HI (ABCC8, KCNJ11, GLUD1, GCK, HADH1, UCP2, MCT1, HNF4A, HNF1A, HK1, PGM1), as well as several syndromic genetic forms of HI (eg, Beckwith-Wiedemann, Kabuki, and Turner syndromes). HI is also the cause of hypoglycemia in transitional neonatal hypoglycemia and in persistent hypoglycemia in various groups of high-risk neonates (such as birth asphyxia, small for gestational age birthweight, infant of diabetic mother). Management of HI is one of the most difficult problems faced by pediatric endocrinologists and frequently requires difficult choices, such as near-total pancreatectomy and/or highly intensive care with continuous tube feedings. For 50 years, diazoxide, a KATP channel agonist, has been the primary drug for infants with HI; however, it is ineffective in most cases with mutations of ABCC8 or KCNJ11, which constitute the majority of infants with monogenic HI.

CONCLUSIONS

Genetic mutation testing has become standard of care for infants with HI and has proven to be useful not only in projecting prognosis and family counseling, but also in diagnosing infants with surgically curable focal HI lesions. (18)F-fluoro-L-dihydroxyphenylalanine ((18)F-DOPA) PET scans have been found to be highly accurate for localizing such focal lesions preoperatively. New drugs under investigation provide hope for improving the outcomes of children with HI.

Congenital hyperinsulinism: global and Japanese perspectives

Over the past 20 years, there has been remarkable progress in the diagnosis and treatment of congenital hyperinsulinism (CHI). These advances have been supported by the understanding of the molecular mechanism and the development of diagnostic modalities to identify the focal form of ATP-sensitive potassium channel CHI. Many patients with diazoxide-unresponsive focal CHI have been cured by partial pancreatectomy without developing postsurgical diabetes mellitus. Important novel findings on the genetic basis of the other forms of CHI have also been obtained, and several novel medical treatments have been explored. However, the management of patients with CHI is still far from ideal. First, state-of-the-art treatment is not widely available worldwide. Second, it appears that the management strategy needs to be adjusted according to the patient's ethnic group. Third, optimal management of patients with the diazoxide-unresponsive, diffuse form of CHI is still insufficient and requires further improvement. In this review, we describe the current landscape of this disorder, discuss the racial disparity of CHI using Japanese patients as an example, and briefly note unanswered questions and unmet needs that should be addressed in the near future.

Congenital hyperinsulinism: current status and future perspectives

The diagnosis and treatment of congenital hyperinsulinism (CHI) have made a remarkable progress over the past 20 years and, currently, it is relatively rare to see patients who are left with severe psychomotor delay. The improvement was made possible by the recent developments in the understanding of the molecular and pathological basis of CHI. Known etiologies include inactivating mutations of the KATP channel genes (ABCC8 and KCNJ11) and HNF4A, HNF1A, HADH, and UCP2 or activating mutations of GLUD1, GCK, and SLC16A1. The understanding of the focal form of KATP channel CHI and its detection by (18)F-fluoro-L-DOPA positron emission tomography have revolutionized the management of CHI, and many patients can be cured without postoperative diabetes mellitus. The incidence of the focal form appears to be higher in Asian countries; therefore, the establishment of treatment systems is even more important in this population. In addition to diazoxide or long-term subcutaneous infusion of octreotide or glucagon, long-acting octreotide or lanreotide have also been used successfully until spontaneous remission. Because of these medications, near-total pancreatectomy is less often performed even for the diazoxide-unresponsive diffuse form of CHI. Other promising medications include pasireotide, small-molecule correctors such as sulfonylurea or carbamazepine, GLP1 receptor antagonists, or mammalian target of rapamycin inhibitors. Unsolved questions in this field include the identification of the remaining genes responsible for CHI, the mechanisms leading to transient CHI, and the mechanisms responsible for the spontaneous remission of CHI. This article reviews recent developments and hypothesis regarding these questions.