Extreme subcutaneous insulin resistance: a misunderstood syndrome

Pancreas transplantation as rescue therapy in a patient with type 1 diabetes and concurrent subcutaneous insulin resistance

Patients with type 1 diabetes and concurrent subcutaneous insulin resistance present unique diagnostic and therapeutic challenges for clinicians. The standard therapeutic approach is the administration of intravenous insulin. Pancreatic transplantation should be considered at an appropriate time, particularly in the event of life-threatening ketoacidosis, hyperglycemia, hypoglycemia, catheter-associated thrombosis, and infections. We present the case of a 24-year-old woman with type 1 diabetes since early childhood and increasingly uncontrollable subcutaneous and intramuscular insulin resistance. Furthermore, we present the diagnostic pathway and therapeutic interventions performed, culminating in pancreatic transplantation as a curative approach. Immediate graft function resulted in optimal glycemic control.

Insulin amyloidosis: A case report

Insulin amyloidosis is a rare form of localized amyloidosis due to insulin aggregation into subcutaneous amyloid fibrils. We describe the case of a 55 years old male with insulin-requiring type 1 diabetes presenting with two non-inflammatory intra-dermal nodules associated with local lymph node enlargement. Diagnosis was confirmed by Congo red coloration of the amyloid deposit and insulin protein identification on mass spectrometry. Insulin amyloidosis is a potential complication of repeated subcutaneous insulin injections. The main risk factor is the intrinsic characteristic of the insulin used. Insulin amyloidosis leads to systemic metabolic consequences such as chronic hyperglycemia or unpredictable hypoglycemia, as well as unesthetic cutaneous lumps or abscesses. Standard-of-care is yet to be defined but mainly rely on therapeutical education of insulin injections, while surgical excision is reported to improve glycemic control in some patients.

A Possible Novel Effect for Dapagliflozin in the Management of Subcutaneous Insulin Resistance Syndrome: A Report of Two Cases

INTRODUCTION

Subcutaneous insulin resistance syndrome (SIRS) is a rare condition in which patients poorly respond to subcutaneous (SC) insulin but maintain a normal response to intravenous (IV) insulin. The underlying pathophysiology remains elusive. Several treatment regimens have been tested for the management of SIRS, none of which included a sodium-glucose cotransporter-2 inhibitor (SGLT-2).

CASE PRESENTATION

Two cases of type 1 diabetes initially achieved adequate glycemic control with subcutaneous insulin. Both cases later progressed into recurrent diabetic ketoacidosis that would resolve following IV insulin administration. Further investigation revealed unresponsiveness to SC, but not IV, insulin and the clinical diagnosis of SIRS was established accordingly. HbA1c values for cases 1 and 2 were 11% on 400 units/day of SC insulin, and 12% on 350 - 400 units/day of SC insulin, respectively. The patients required very high doses of intramuscular (IM) insulin. Subsequently, dapagliflozin as adjunct therapy significantly reduced the patients' IM insulin requirements beyond the anticipated dose reduction. Ultimately, case 1 achieved an HbA1c of 7 - 8% on 90 units/day of IM insulin and 10 mg/day of dapagliflozin, and case 2 achieved an HbA1c of 7 - 8% on 120 units/day of IM insulin and 10 mg/day of dapagliflozin.

CONCLUSIONS

These are the first reported cases of SIRS in which dapagliflozin, an SGLT-2 inhibitor, was used. The substantial reduction in the IM insulin dose following the addition of dapagliflozin in our reported cases of SIRS suggests a possible novel mechanism for dapagliflozin beyond its glucosuric effects. In this report, we present a hypothetical basis for this possible novel mechanism.

Case of type 2 diabetes mellitus with edema resulting in subcutaneous insulin resistance syndrome

Subcutaneous insulin resistance syndrome caused by obesity, induration at the injection site, skin temperature and other factors is common clinically, whereas resistance events caused by edema are relatively rare. This article introduced a case of a woman with type 2 diabetes mellitus with heart failure edema. Her blood glucose control was significantly associated with the level of edema. Excluding other factors, it can be concluded that edema might lead to subcutaneous insulin resistance syndrome, even if the edema at the injection site is not obvious.

Severe insulin resistance syndromes

Severe insulin resistance syndromes are a heterogeneous group of rare disorders characterized by profound insulin resistance, substantial metabolic abnormalities, and a variety of clinical manifestations and complications. The etiology of these syndromes may be hereditary or acquired, due to defects in insulin potency and action, cellular responsiveness to insulin, and/or aberrations in adipose tissue function or development. Over the past decades, advances in medical technology, particularly in genomic technologies and genetic analyses, have provided insights into the underlying pathophysiological pathways and facilitated the more precise identification of several of these conditions. However, the exact cellular and molecular mechanisms of insulin resistance have not yet been fully elucidated for all syndromes. Moreover, in clinical practice, many of the syndromes are often misdiagnosed or underdiagnosed. The majority of these disorders associate with an increased risk of severe complications and mortality; thus, early identification and personalized clinical management are of the essence. This Review aims to categorize severe insulin resistance syndromes by disease process, including insulin receptor defects, signaling defects, and lipodystrophies. We also highlight several complex syndromes and emphasize the need to identify patients, investigate underlying disease mechanisms, and develop specific treatment regimens.

Case of subcutaneous insulin resistance syndrome treated with ultra-rapid insulin lispro

Subcutaneous insulin resistance syndrome is a rare condition that causes difficulty in glycemic control due to severe resistance to subcutaneous insulin injections. We herein present a case of a 40‐year‐old woman with type 2 diabetes mellitus who had been diagnosed with subcutaneous insulin resistance syndrome since the age of 29 years, and had been persistently treated with continuous subcutaneous insulin infusion using a mixture of insulin lispro and heparin. The patient was switched from insulin lispro plus heparin to ultra‐rapid insulin lispro; given that it contains treprostinil and citrate, it is expected to have similar effects as heparin, and shows similar glucose‐lowering effects and insulin absorption. Our results suggest that treatment with ultra‐rapid insulin lispro is effective for subcutaneous insulin resistance syndrome.

Clinical features resembling subcutaneous insulin resistance observed in a patient with type 2 diabetes and severe COVID-19-associated pneumonia: a case report

We report the case of a 52-year-old hyperglycemic woman with type 2 diabetes and severe coronavirus disease 2019 (COVID-19)-associated pneumonia, possibly involving the subcutaneous insulin resistance (SIR) syndrome. After admission for pneumonia, her average daily blood glucose (BG) levels remained at 300-400 mg/dL, although the required dosage of subcutaneous insulin markedly increased (~ 150 units/day; ~ 2.63 units/kg/day). Furthermore, the patient had generalized edema along with hypoalbuminemia, developed extensive abdominal purpuras, and had increased plasma D-dimer levels during treatment, suggestive of coagulation abnormalities. Therefore, intravenous infusion of regular insulin was initiated. The BG level subsequently decreased to < 200 mg/dL 2 days after administering 18 units/day of insulin infusion and 118 units/day of subcutaneous insulin, suggesting that subcutaneous insulin alone might have been ineffective in reducing hyperglycemia, which is clinically consistent with the characteristics of an SIR syndrome. Impaired skin microcirculation arising from coagulation abnormalities, subcutaneous edema associated with inflammation-related hypoalbuminemia or vascular hyperpermeability, and/or reduction in subcutaneous blood flow due to COVID-19-induced downregulation of angiotensin-converting enzyme 2 might be associated with the development of pathological conditions that resemble SIR syndrome, leading to impaired subcutaneous insulin absorption.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13340-021-00500-x.

Insulin and heparin challenge tests are useful for choosing an optimal insulin regimen in a case of subcutaneous insulin resistance

A 38-year-old woman with type 1 diabetes, whose fasting plasma glucose levels were >500 mg/dL under 176 U/day of subcutaneous insulin injection, was admitted to Nippon Medical School Hospital, Tokyo, Japan. When insulin was administered intravenously, she was able to maintain favorable glycemic control even under 24 U/day of regular insulin, showing that she was accompanied by subcutaneous insulin resistance. To choose an optimal insulin regimen, we carried out subcutaneous insulin challenge tests without or with heparin mixture, and found a cocktail of insulin lispro and heparin could reduce blood glucose levels markedly. As a consequence, she achieved favorable blood glucose control by continuous subcutaneous insulin infusion of the cocktail. In summary, the insulin and heparin challenge tests are useful for choosing an optimal insulin regimen in cases of subcutaneous insulin resistance.

USE OF INHALED INSULIN IN A PATIENT WITH SUBCUTANEOUS INSULIN RESISTANCE SYNDROME: A RARE CONDITION

Objective

Subcutaneous insulin resistance syndrome (SIRS) is a rare entity, characterized by increased resistance to subcutaneous insulin and normal sensitivity to intravenous insulin, with no increase in circulating insulin antibodies. Little is known about its pathophysiology, but it has been suggested to occur due to rapid subcutaneous degradation of insulin. Multiple treatment modalities have been used in the past to treat this condition.

Methods

We illustrate a case of a 17-year-old girl with type 1 diabetes mellitus (T1DM), presenting with recurrent episodes of diabetic ketoacidosis (DKA) due to resistance to subcutaneously delivered insulin.

Results

We describe the challenges faced while attempting different modalities during her hospital stay, and eventually using inhaled insulin, which was recently approved by the Food and Drug Administration for use in nonpregnant adults with T1DM.

Conclusion

SIRS is a difficult condition that may lead to patient frustration and carries a serious risk of recurrent DKA. We described this case to create awareness about SIRS, provide insight into the challenges of its management, and report the use of inhaled insulin to successfully dose meal-time insulin, along with intramuscular glargine for basal insulin.

A New Optimized Percutaneous Access System for CIPII

In recent years, continuous intraperitoneal insulin infusion (CIPII) has become a favored treatment alternative for patients with subcutaneous insulin resistance, mainly due to its ability of mimicking physiological conditions of insulin absorption. CIPII has been shown to improve glycemic control as well as to reduce hypoglycemic events and to lead to increased patient satisfaction and quality of life (QoL). Among CIPII delivery systems, Diaport stands out due to its low side effects, its demonstrated clinical efficacy and the potential for integration into closed-loop systems.

Insulin amyloid at injection sites of patients with diabetes

The formation of insulin amyloid can dramatically impact glycemic control in patients with diabetes, making it an important therapeutic consideration. In addition, the cost associated with the excess insulin required by patients with amyloid is estimated to be $3K per patient per year, which adds to the growing financial burden of this disease. Insulin amyloid has been observed with every mode of therapeutic insulin administration (infusion, injection and inhalation), and the number of reported cases has increased significantly since 2002. The new cases represent a much broader demographic, and include many patients who have used exclusively human insulin and human insulin analogs. The reason for the increase in case reports is unknown, but this review explores the possibility that changes in patient care, improved differential diagnosis and/or changes in insulin type and insulin delivery systems may be important factors. The goal of this review is to raise key questions that will inspire proactive measures to prevent, identify and treat insulin amyloid. Furthermore, this comprehensive examination of insulin amyloid can provide insight into important considerations for other injectable drugs that are prone to form amyloid deposits.

Intraperitoneal insulin therapy for a patient with type 1 diabetes with insulin injection site inflammation

A 36-year-old man with type 1 diabetes developed skin inflammation at the site of subcutaneous insulin injection after 10 years of basal bolus subcutaneous insulin therapy. This inflammation led to poor insulin absorption, poorly controlled blood glucose and subsequently to ketoacidosis. The problem persisted despite a trial of continuous subcutaneous insulin infusion. The patient went on to be treated with continuous intraperitoneal insulin infusion. Three months after the procedure, he was achieving good glucose control and was able to resume his normal life, with the only complication being an episode of cellulitis surrounding the port site.

Analytical and clinical challenges in a patient with concurrent type 1 diabetes, subcutaneous insulin resistance and insulin autoimmune syndrome

A lean 15-year-old girl was diagnosed with type 1 diabetes based on symptomatic hyperglycaemia and positive anti-islet cell antibodies. Glycaemia was initially stabilised on twice-daily mixed insulin. After 11 months from the time of diagnosis, she complained of hyperglycaemia and ketosis alternating with hypoglycaemia. This progressively worsened until prolonged hospital admission was required for treatment of refractory hypoglycaemia. A high titre of anti-insulin antibodies was detected associated with a very low recovery of immunoreactive (free) insulin from plasma after precipitation with polyethylene glycol, suggesting the presence of insulin in bound complexes. Insulin autoimmune syndrome was diagnosed and metabolic fluctuations were initially managed supportively. However, due to poor glucose control, immunosuppressive therapy was initiated first with steroids and plasmapheresis and later with anti-CD20 antibody therapy (Rituximab). This treatment was associated with a gradual disappearance of anti-insulin antibodies and her underlying type 1 diabetes has subsequently been successfully managed with an insulin pump.

LEARNING POINTS

Anti-insulin antibodies may result in low levels of free insulin.Polyclonal anti-insulin antibodies can interfere with the pharmacological action of administered insulin, resulting in hypoglycaemia and insulin resistance, due to varying affinities and capacities.In this patient, rituximab administration was associated with a gradual disappearance of anti-insulin antibodies.It is hypothesised that this patient had subcutaneous insulin resistance (SIR) caused by insulin capture at the tissue level, either by antibodies or by sequestration.A prolonged tissue resistance protocol may be more appropriate in patients with immune-mediated SIR syndrome.

[Extreme subcutaneous and intramuscular insulin resistance at type 1 diabetes mellitus]

Insulin resistance signs reduced cellular response to this hormone and dysfunction of glucose transport to intracellular compartment. This phenomenon is associated to genetic factors and principally behavior factors correlating to obesity and its comorbidities, as type 2 diabetes mellitus, hypertension and dyslipidemia. However clinical factors of insulin resistance are still present at not obese type 1 diabetes in a known syndrome called type 1 diabetes mellitus with resistance to insulin administered subcutaneously and intramuscularly (DRIASM). This is a rare condition that consists into insulin resistance at subcutaneously and intramuscularly use and normal or near to normal sensitivity at intravenously way. Treatments until now proposed are ineffective and are related to frequent fails and complications. We report here two cases of DRIASM in 45 and 46 female patients that are different from others yet related because they have late diabetes type 1, sustained hyperglycemia associated to catabolic, microangiopathy and neuropathic complications without any ketoacidosis episode. The treatment vary from alternative ways for insulin infusion to inscription to a possible performance of pancreas transplantation like a experiment of definitive treatment. This report was approved by Research Ethic Committee from São José do Rio Preto medical school.

Clinical approach to the patient with diabetes mellitus and very high insulin requirements

A number of patients with diabetes require very high (> 2 Ukg⁻¹ day⁻¹), or extremely high (> 3 Ukg⁻¹ day⁻¹), insulin doses for the management of their hyperglycemia. Unfortunately, many of the physicians who treat these patients limit themselves to prescribing ever higher doses of insulin, without questioning why. Furthermore, when the insulin requirements get to be extreme, demanding an explanation, clinicians are frequently lost in a sea of literature where there is not a single paper dealing with this problem systematically. A systematic approach to the evaluation of these patients is necessary to facilitate an appropriate diagnosis, select the most reasonable therapy, and hopefully improve the long-term outcome of these patients. This manuscript intends to provide the clinician with a review of the literature pertinent for the differential diagnosis, work-up, and management of these patients. We will review the definitions of insulin sensitivity during normality, the various degrees or categories of insulin resistance, and the expected insulin requirements during each of these states. Subsequently, we propose a simple alphabetic mnemonic approach to help remember the differential diagnosis, and a clinical algorithm to help guide the work-up of these patients. Lastly, we briefly discuss general management considerations in these conditions.

Successful treatment of severe subcutaneous insulin resistance with inhaled insulin therapy

The potential of inhaled insulin therapy for severe resistance to subcutaneous insulin was tested in a 7-yr old boy with type 1 diabetes mellitus. The efficiency of 1 mg inhaled insulin (Exubera) was examined by a 4-h euglycemic clamp study. During the clamp, the glucose infusion rate started to increase 25 min after inhalation and peaked 120 min after inhalation. Subsequently, a trial of inhaled insulin monotherapy was initiated consisting of pre-meal inhalations and one inhalation during the night. Since glycemic control remained fair (HbA1c approximately 8.5%), this therapy was continued. Over the ensuing 18 months, mild keto-acidosis occurred twice during gastro-enteritis. Inhaled insulin was well tolerated and pulmonary function did not deteriorate. We conclude that severe resistance to subcutaneous insulin does not preclude sufficient absorption of insulin delivered by pulmonary.

Extreme subcutaneous, intramuscular and inhaled insulin resistance treated by pancreas transplantation alone

Diabetes mellitus with resistance to insulin administered subcutaneously or intramuscularly (DRIASM) is a rare syndrome and is usually treated with continuous intravenous insulin infusion. We present here two cases of DRIASM in 16 and 18 years female patients that were submitted to pancreas transplantation alone (PTA). Both were diagnosed with type 1 diabetes as young children and had labile glycemic control with recurrent episodes of diabetic ketoacidosis. They had prolonged periods of hospitalization and complications related to their central venous access. Exocrine and endocrine drainages were in the bladder and systemic, respectively. Both presented immediate graft function. In patient 1, enteric conversion was necessary due to reflux pancreatitis. Patient 2 developed mild postoperative hyperglycemia in spite of having normal pancreas allograft biopsy and that was attributed to her immunosuppressive regimen. Patient 1 died 9 months after PTA from septic shock related to pneumonia. In 8 months of follow-up, Patient 2 presented optimal glycemic control without the use of antidiabetic agents. In conclusion, PTA may be an alternative treatment for DRIASM patients.

Management strategies for brittle diabetes

Type 1 diabetes is an intrinsically unstable condition. However, the term "brittle diabetes" is reserved for those cases in which the instability, whatever its cause, results in disruption of life and often recurrent and/or prolonged hospitalization. It affects 3/1000 insulin-dependent diabetic patients, mainly young women. Its prognosis is poor with lower quality of life scores, more microvascular and pregnancy complications and shortened life expectancy. Three forms have been described: recurrent diabetic ketoacidosis, predominant hypoglycemic forms and mixed instability. Main causes of brittleness include malabsorption, certain drugs (alcohol, antipsychotics), defective insulin absorption or degradation, defect of hyperglycemic hormones especially glucocorticoid and glucagon, and above all delayed gastric emptying as a result of autonomic neuropathy. Psychosocial factors are very important and factitious brittleness may lead to a self-perpetuating condition. The assessment of brittle diabetes requires quantification of the variability of blood glucose levels. To quantify instability, measures which have been developed, include Mean Amplitude of the largest Glycemic Excursions (MAGE), Mean Of Daily Differences (MODD), Lability Index (LI), Low Blood Glucose Index (LBGI), Clarke's score, Hyposcore, and continuous blood glucose monitoring. Once psychogenic problems have been excluded, therapeutic strategies require firstly, the treatment of underlying organic causes of the brittleness whenever possible and secondly optimising standard insulin therapy using analogues, multiple injections and consideration of Continuous Subcutaneous Insulin Infusion. Alternative approaches may still be needed for the most severely affected patients. Isolated islet transplantation (IIT), which restores glucose sensing, should be considered in cases of hypoglycaemic unawareness and/or lability especially if the body mass index is < 25, but with current immunosuppressive protocols patients must have normal renal function and preferably no plans for pregnancy. Implantable pumps have advantages for patients who either weigh more than 80 kgs or have abnormalities of kidney or liver function or are highly sensitised.

Subcutaneous insulin resistance successfully circumvented on long term by peritoneal insulin delivery from an implantable pump in four diabetic patients

Extreme subcutaneous insulin resistance is a rare syndrome characterized by a severe resistance to subcutaneous (S/C) insulin together with persistence of normal or near normal intravenous (IV) insulin sensitivity. Its pathophysiology is unknown, although increased insulin degrading activity has been reported in the S/C adipose tissue fraction in some cases. Until now, proposed treatments have been disappointing. We report 4 cases who were successfully treated by intraperitoneal (IP) route.

METHODS

The diagnosis of subcutaneous insulin resistance was based upon following combined conditions: resistance to hypoglycaemic action of subcutaneous insulin but normal or near normal sensitivity to IV or IP insulin.

RESULTS

4 patients among those followed by EVADIAC group met these criteria: 3 with type 1 diabetes (C peptide=0), the last one with unexplained non insulin-deficient diabetes (no anti-GAD antibodies, C peptide=5 ng/ml). All of them had been treated with subcutaneous insulin therapy without success despite huge doses (up to 4000 IU/day in two patients). The 3 type 1 diabetic patients presented with a history of repeated ketoacidosis episodes. A treatment of insulin mixed with aprotinin had been proposed to 2 patients without success. The IV insulin sensitivity was proved to be normal in two patients by euglycaemic clamp data. A skin biopsy was performed in 1 patient. An accumulation of insulin in the derma was revealed with no increase of degradation products of insulin. In these 4 patients, a dramatic improvement of diabetes control was obtained by IP insulin delivery from an implantable pump (HbA1c decrease by at least 3%).

CONCLUSION

Although pathophysiology of the subcutaneous insulin resistance syndrome remains unexplained, our data show that intra-peritoneal insulin therapy from an implantable pump allows diabetes control in patients affected by this uncommon but severely disabling condition.