[Donohue syndrome and use of continuous subcutaneous IGF1 pump therapy].

Donohue syndrome (DS), also called Leprechaunism, is the most severe form of insulin resistance associated with biallelic mutations in INSR gene (OMIM: 147670). The approximate incidence of this syndrome is 1 per 1000000 births. Patients are present with typical clinical features such as intrauterine growth retardation, facial dysmorphism, severe metabolic disturbances, hepatomegaly and hypertrophic cardiomyopathy. Most DS patients die within the first two years of life due to respiratory infections, severe hypoglycemia or progressive cardiomyopathy. Treatment options are limited and no specific therapy exist for DS. Given the similarities between insulin and insulin-like growth factor 1 (IGF-1) receptors, recombinant human IGF-1 (rhIGF-1) has been used to treat severe insulin resistance including DS.We report the case of a male patient with genetically confirmed Donohue syndrome, successfully treated with continuous subcutaneous IGF1 infusion via insulin pump. We observed improvement of glycemic control, liver function and cardiac hypertrophy regression following 15-month IGF1 therapy.

Long-Term Effects of Metreleptin in Rabson-Mendenhall Syndrome on Glycemia, Growth, and Kidney Function.

CONTEXT: Rabson-Mendenhall syndrome (RMS) is caused by biallelic pathogenic variants in the insulin receptor gene (INSR) leading to insulin-resistant diabetes, microvascular complications, and growth hormone resistance with short stature. Small, uncontrolled studies suggest that 1-year treatment with recombinant leptin (metreleptin) improves glycemia in RMS. OBJECTIVE: This study aimed to determine effects of long-term metreleptin in RMS on glycemia, anthropometrics, the growth hormone axis, and kidney function. METHODS: We compared RMS patients during nonrandomized open-label treatment with metreleptin (≥ 0.15 mg/kg/day) vs no metreleptin over 90 months (5 subjects in both groups at different times, 4 only in metreleptin group, 2 only in control group). Main outcome measures were A1c; glucose; insulin; 24-hour urine glucose; standard deviation scores (SDS) for height, weight, body mass index (BMI), and insulin-like growth factor 1 (IGF-1); growth hormone; and estimated glomerular filtration rate. RESULTS: Over time, metreleptin-treated subjects maintained 1.8 percentage point lower A1c vs controls (P = 0.007), which remained significant after accounting for changes in insulin doses. Metreleptin-treated subjects had a reduction in BMI SDS, which predicted decreased A1c. Growth hormone increased after metreleptin treatment vs control, with no difference in SDS between groups for IGF-1 or height. Reduced BMI predicted higher growth hormone, while reduced A1c predicted higher IGF-1. CONCLUSION: Metreleptin alters the natural history of rising A1c in RMS, leading to lower A1c throughout long-term follow-up. Improved glycemia with metreleptin is likely attributable to appetite suppression and lower BMI SDS. Lower BMI after metreleptin may also worsen growth hormone resistance in RMS, resulting in a null effect on IGF-1 and growth despite improved glycemia.

Mecasermin in Insulin Receptor-Related Severe Insulin Resistance Syndromes: Case Report and Review of the Literature.

Mutations in the insulin receptor (INSR) gene underlie rare severe INSR-related insulin resistance syndromes (SIR), including insulin resistance type A, Rabson⁻Mendenhall syndrome and Donohue syndrome (DS), with DS representing the most severe form of insulin resistance. Treatment of these cases is challenging, with the majority of DS patients dying within the first two years of life. rhIGF-I (mecasermin) has been reported to improve metabolic control and increase lifespan in DS patients. A case report and literature review were completed. We present a case involving a male patient with DS, harbouring a homozygous mutation in the INSR gene (c.591delC). Initial rhIGF-I application via BID (twice daily) injection was unsatisfactory, but continuous subcutaneous rhIGF-I infusion via an insulin pump improved weight development and diabetes control (HbA1c decreased from 10 to 7.6%). However, our patient died at 22 months of age during the course of a respiratory infection in in Libya. Currently available data in the literature comprising more than 30 treated patients worldwide seem to support a trial of rhIGF-I in SIR. rhIGF-I represents a treatment option for challenging SIR cases, but careful consideration of the therapeutic benefits and the burden of the disease is warranted. Continuous application via pump might be advantageous compared to single injections.

Treatment of Diabetic Ketoacidosis With Intravenous U-500 Insulin in a Patient With Rabson-Mendenhall Syndrome: A Case Report.

Rabson-Mendenhall syndrome is a rare genetic disorder resulting from mutations in the insulin receptor and is associated with high degrees of insulin resistance. These patients are prone to complications secondary to their hyperglycemia including diabetic ketoacidosis (DKA). We report the case of a 19-year-old male with Rabson-Mendenhall syndrome presenting with DKA who required doses of up to 500 U/h (10.6 U/kg/h) of insulin. The patient's insulin infusion was originally compounded with U-100 regular insulin, although to minimize volume, the product was compounded with U-500 insulin. The DKA eventually resolved requiring infusion rates ranging from 400 to 500 U/h. Although numerous opportunities for medication errors exist with the use of U-500 insulin, this case outlines the safe use of concentrated intravenous insulin when clinically indicated for patients requiring extremely high doses of insulin to control blood glucose.

Donohue syndrome and use of continuous subcutaneous insulin pump therapy.

Donohue syndrome is a rare autosomal recessive condition caused by severe loss-of-function mutations in the insulin receptor (INSR) gene. The diagnosis is made on clinical, biochemical and genetic grounds. Mutations are found on chromosome 19p13.2, and code for mutations in the INSR gene. Treatment is challenging and often unsuccessful, and relies on maintaining normoglycaemia and avoiding fasting; in some patients, recombinant human insulin-like growth factor (rhIGF-1) has been trialled. The prognosis is poor, with most babies dying in infancy. Ethically, it is important to consider the benefit versus burden of treatment, the quality of life of the surviving patient and the parents' wishes, when making decisions regarding withholding or withdrawing care.

Ten-year improvement of insulin resistance and growth with recombinant human insulin-like growth factor 1 in a patient with insulin receptor mutations resulting in leprechaunism.

AIM: Leprechaunism, a rare genetic disease resulting from mutations in two alleles of the insulin receptor gene, is characterized by severe insulin resistance, retarded growth and, usually, premature death. The ability of treatment with recombinant human insulin-like growth factor 1 (rhIGF1) to improve metabolic and clinical parameters in the long-term is still controversial. METHODS: Mutations were looked for in the insulin receptor gene of a four-month-old female baby with leprechaunism. The patient's skin fibroblasts were analyzed for response to insulin and IGF1. At the clinical level, the very long-term effects of treatment with rhIGF1/rhIGFBP3 were evaluated by clinical and metabolic parameters. RESULTS: The patient's diagnosis was based on compound heterozygous mutations in two alleles of the insulin receptor gene, thus confirming leprechaunism. Cultured fibroblasts showed a decreased number of insulin receptors and were insulin-resistant. However, IGF1 was able to stimulate IGF1 receptor signalling, suggesting possible activation of a salvage pathway. Treatment with IGF1/IGFBP3 for 8.7 years, then IGF1 for 2 years, resulted in normalization of circulating levels of IGF1 and IGFBP3. Large daily variations in glycaemia and insulinaemia persisted, but mean glycaemia decreased. Regarding growth, the patient's BMI Z score normalized and length/height score improved. Our patient presented normal neurological development and academic achievement. The treatment was free of adverse effects. CONCLUSION: Our results provide evidence that rhIGF1 with and without rhIGFBP3 can prevent fatal outcomes, and improve growth and metabolic parameters, for more than 10 years in a patient with leprechaunism. Long-term rhIGF1 for severe insulin resistance syndrome should be considered.

Continuous subcutaneous IGF-1 therapy via insulin pump in a patient with Donohue syndrome.

Donohue syndrome (DS) is a severe form of congenital insulin resistance due to mutation(s) in the insulin receptor (INSR) gene. Given the similarities between insulin and insulin-like growth factor 1 (IGF-1) receptors, recombinant human IGF-1 (rhIGF-1) has been used to treat severe insulin resistance due to INSR mutation(s). Traditional subcutaneous therapy may be limited by the shortened IGF-1 half-life in these patients. We report the case of a female with molecularly confirmed DS treated with continuous rhIGF-1 therapy via an insulin pump. With treatment, the patient's hemoglobin A1c decreased from 9.8% to 8.8%, and her weight increased by 0.8 kg. Development of an ovarian tumor complicated her course, but it was unclear whether this was related to rhIGF-1 therapy. Limited treatment options exist for patients with DS. The use of continuous rhIGF-1 via an insulin pump may be a viable option, although further experience is needed to establish safety and efficacy.

Metreleptin improves blood glucose in patients with insulin receptor mutations.

CONTEXT: Rabson-Mendenhall syndrome (RMS) is caused by mutations of the insulin receptor and results in extreme insulin resistance and dysglycemia. Hyperglycemia in RMS is very difficult to treat, and patients are at risk for early morbidity and mortality from complications of diabetes. OBJECTIVE: Our objective was to study 1-year effects of recombinant human methionyl leptin (metreleptin) in 5 patients with RMS and 10-year effects in 2 of these patients. DESIGN AND SETTING: We conducted an open-label nonrandomized study at the National Institutes of Health. PATIENTS: Patients were adolescents with RMS and poorly controlled diabetes. INTERVENTION: Two patients were treated with escalating doses (0.02 up to 0.22 mg/kg/d) of metreleptin for 10 years, including 3 cycles of metreleptin withdrawal and reinitiation. In all 5 patients, 1-year effects of metreleptin (0.22 mg/kg/d) were studied. OUTCOME MEASURES: Hemoglobin A1c (HbA1c) and body mass index (BMI) z-scores were evaluated every 6 months. RESULTS: HbA1c decreased from 11.4% ± 1.1% at baseline to 9.3% ± 1.9% after 6 months and 9.7% ± 1.6% after 12 months of metreleptin (P = .007). In patients treated for 10 years, HbA1c declined with each cycle of metreleptin and rose with each withdrawal. BMI z-scores declined from -1.4 ± 1.8 at baseline, to -2.6 ± 1.6 after 12 months of metreleptin (P = .0006). Changes in BMI z-score correlated with changes in HbA1c (P < .0001). CONCLUSIONS: Metreleptin treatment for 12 months was associated with a 1.7% reduction in HbA1c; part of this improvement was likely mediated via decreased BMI. Metreleptin is a promising treatment option for RMS, but additional therapies are needed to achieve HbA1c targets.

Syndrome of extreme insulin resistance (Rabson-Mendenhall phenotype) with atrial septal defect: clinical presentation and treatment outcomes.

Syndrome of extreme insulin resistance (SEIR) is a rare spectrum disorder with a primary defect in insulin receptor signalling, noted primarily in children, and is often difficult to diagnose due to the clinical heterogeneity.SEIR was diagnosed in an adolescent girl with facial dysmorphism,exuberant scalp and body hair, severe acanthosis, lipoatrophy, dental abnormalities, and short stature (Rabson-Mendenhall phenotype). She had elevated fasting (422.95 pmol/L) and post-glucose insulin levels(>2083 pmol/L). Total body fat was decreased (11%; dual-energy X-ray absorptiometry). Basal growth hormone (GH) was increased (7.9 µg/L)with normal insuline-like growth factor 1 (37.6 nmol/L) suggestive of GH resistance. She had fatty liver and polycystic ovaries. Echocardiography revealed ostium secundum type atrial septal defect (ASD). Blood glucose normalized with pioglitazone (30 mg/day). Delayed development, severe insulin resistance, mild hyperglycemia, absence of ketosis, and remarkable response of hyperinsulinemia and hyperglycemia to pioglitazone which persisted even after 1 year of diagnosis are some of the notable features of this patient. This is perhaps the first report of occurrence of congenital heart disease (ASD) in a patient of SEIR (Rabson-Mendenhall phenotype). This report highlights the clinical features of SEIR and the role of insulin sensitizers like pioglitazone in the management of such patients.

Leprechaunism (Donohue syndrome): a case bearing novel compound heterozygous mutations in the insulin receptor gene.

Leprechaunism (Donohue syndrome) is the most severe type of insulin receptor (INSR) gene anomaly with the majority of patients surviving for only 2 years. We report a surviving 2 -year-old male with leprechaunism, bearing novel compound heterozygous mutations in the INSR. The patient is a Japanese boy with acanthosis nigricans, lack of subcutaneous fat, hirsutism, thick lips, gum hypertrophy and extremely high insulin levels (6702 mU/mL). He was as having identified novel compound heterozygous mutations in INSR (p.T910M and p. E1047K). At 24 day-old, recombinant human insulin-like growth factor 1 (rh-IGF1) treatment was started because of poor weight gain. At 2 years old, the patient's serum glucose level and HbA1C value had worsened, and both a bolus of rh-IGF-1 and a subcutaneous injection of a rapid-acting insulin analog after meals, in addition to α-glycosidase inhibitor, were initiated from 2 years onward. Oxygen administration and biphasic positive airway pressure treatment were also initiated from 2 years old due to upper airway obstruction with adenoidal hypertrophy. In the experiments conducted using COS7 cells homozygously transfected with the INSR mutation, T910M INSR failed to process the proreceptor and decreased insulin-stimulated tyrosine phosphorylation. E1047K INSR resulted in a complete absence of insulin-stimulated tyrosine phosphorylation. These findings suggest the near absence of INSR in this patient. We consider that the rhIGF1 treatment contributed to his long survival, but it was not able to prevent his diabetic condition. Our report provides important insights into the function of INSR, and for the treatment of leprechaunism.

Two novel insulin receptor gene mutations in a patient with Rabson-Mendenhall syndrome: the first Korean case confirmed by biochemical, and molecular evidence.

Rabson-Mendenhall syndrome (RMS) is a rare syndrome manifested by extreme insulin resistance with hyperinsulinemia, acanthosis nigricans, tooth dysplasia and growth retardation. Our patient was first noted at the age of 8 months due to pigmentations on skin-folded areas. Initial laboratory tests showed normal fasting glucose (69 mg/dL). Fasting insulin level was severely elevated, up to 554.6 µIU/mL, and c-peptide level was increased, up to 13.81 ng/mL. However, hemoglobin A1c was within normal range (4.8%). He is now 11 yr old. His growth development followed the 5-10th percentile and oral hypoglycemic agents are being administered. The last laboratory results showed insulin 364.1 µIU/mL, C-peptide 4.30 ng/mL, and hemoglobin A1c 7.6%. The boy was a compound heterozygote for the c.90C > A and c.712G > A mutations of the insulin receptor gene, INSR, which are nonsense and missense mutations. In summary, we report the first Korean case of RMS, which was confirmed by two novel mutations of the INSR.

Two Novel Insulin Receptor Gene Mutations in a Patient with Rabson-Mendenhall Syndrome: The First Korean Case Confirmed by Biochemical, and Molecular Evidence

Rabson-Mendenhall syndrome (RMS) is a rare syndrome manifested by extreme insulin resistance with hyperinsulinemia, acanthosis nigricans, tooth dysplasia and growth retardation. Our patient was first noted at the age of 8 months due to pigmentations on skin-folded areas. Initial laboratory tests showed normal fasting glucose (69 mg/dL). Fasting insulin level was severely elevated, up to 554.6 microIU/mL, and c-peptide level was increased, up to 13.81 ng/mL. However, hemoglobin A1c was within normal range (4.8%). He is now 11 yr old. His growth development followed the 5-10th percentile and oral hypoglycemic agents are being administered. The last laboratory results showed insulin 364.1 microIU/mL, C-peptide 4.30 ng/mL, and hemoglobin A1c 7.6%. The boy was a compound heterozygote for the c.90C > A and c.712G > A mutations of the insulin receptor gene, INSR, which are nonsense and missense mutations. In summary, we report the first Korean case of RMS, which was confirmed by two novel mutations of the INSR.

Sustained regression of florid diabetic retinopathy in a patient with Donohue syndrome (leprechaunism).

PURPOSE: Leprechaunism is a rare congenital syndrome caused by mutations of the insulin receptor gene, transmitted in an autosomal recessive pattern. Insulin growth factor-1 (IGF-1) treatment can be a therapeutic option in this syndrome by its insulin-like effects. Nevertheless, it is of note that IGF-1 has also an angiogenic activity. METHODS: Fundus examination by ophthalmoscopy, fluorangiography, and laser treatment were performed. RESULTS: A 17-year-old girl with leprechaunism, under treatment with high doses of insulin, presented a florid diabetic retinopathy. The large neovascularization of the disk regressed after treatment with argon laser panretinal photocoagulation. Five years after treatment, the patient maintained good vision. CONCLUSIONS: This clinical case is of interest for 2 reasons: 1) the large retinal neovascularization was likely due to the high insulin dosages; 2) this is the first case in which a sustained regression of retinal neovascularization has been observed after laser treatment in leprechaunism.