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

Youngest pancreas transplantation alone in the UK for type 1 diabetes and severe subcutaneous insulin resistance

A child diagnosed with type 1 diabetes mellitus during her middle childhood developed severe subcutaneous insulin resistance as her illness progressed. This resulted in recurrent episodes of diabetic ketoacidosis and hypoglycaemia, eventually leading to intravenous insulin dependence. Despite intensive investigations, an organic cause was not found.The patient was in her late adolescence when she eventually received her pancreas transplant alone, the youngest patient in the UK. This case highlights severe peripheral insulin resistance as an important indication for whole organ pancreas transplantation in the paediatric population, as well as early recognition in the failure of conventional medical therapy.

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.

Finding the right route for insulin delivery - an overview of implantable pump therapy

INTRODUCTION

Implantable pump therapy adopting the intraperitoneal route of insulin delivery has been available for the past three decades. The key rationale for implantable pump therapy is the restoration of the portal-peripheral insulin gradient of the normal physiology. Uptake in clinical practice is limited to specialized centers and selected patient populations. Areas covered: Implantable pump therapy is discussed, including technical aspects, rationale for its use, and glycemic and non-glycemic effects. Target populations, summaries of clinical studies and issues related to implantable pump therapy are highlighted. Limitations of implantable pump therapy and its future outlook in clinical practice are presented. Expert opinion: Although intraperitoneal insulin delivery appears closer to the normal physiology, technical, pharmacological, and costs barriers prevent a wider adoption. Evidence from clinical studies remains scarce and inconclusive. As a consequence, the use of implantable pump therapy will be confined to a small population unless considerable technological progress is made and well-conducted studies can demonstrate glycemic and/or non-glycemic benefits justifying wider application.

Intraperitoneal insulin infusion: treatment option for type 1 diabetes resulting in beneficial endocrine effects beyond glycaemia

Continuous intraperitoneal insulin infusion (CIPII) is a treatment option for patients with type 1 diabetes mellitus who fail to reach adequate glycaemic control despite intensive subcutaneous (SC) insulin therapy. CIPII has clear advantages over SC insulin administration in terms of pharmacokinetic and pharmacodynamic properties and has been shown to improve glycaemic regulation. Due to the delivery of insulin predominantly in the portal vein, as opposed to systemically, CIPII offers a unique research model to investigate the effects of insulin on endocrine and metabolic parameters in vivo. The aim of the present article is to provide an overview of the literature with respect to the effects of CIPII on glucose management, quality of life, complications and costs, with additional focus on metabolic and endocrine aspects. Finally, future use and research objectives are discussed.

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.

[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.

Circulating insulin antibodies: influence of continuous subcutaneous or intraperitoneal insulin infusion, and impact on glucose control

The purification of animal insulin preparations and the use of human recombinant insulin have markedly reduced the incidence, but not completely suppressed, the development of anti-insulin antibodies (IAs). Advances in technologies concerning the mode of delivery of insulin, i.e. continuous subcutaneous insulin infusion (CSII), continuous peritoneal insulin infusion (CPII) and more recently inhaled insulin administration, appear to significantly increase circulating levels of immunoglobulin G (IgG) anti-IAs in diabetic patients. However, the increase is usually moderate and mostly transient as compared to previous observations with poorly purified animal insulin preparations. The clinical impact of these circulating anti-IAs remains unclear. Nevertheless, several studies have suggested that antibodies could retard insulin action, leading to a worsening of postprandial hyperglycaemia and/or serve as a carrier, thus leading to unexpected hypoglycaemia. CPII may be associated with more marked and sustained increase in IAs levels, possibly related to the use of an unstable insulin and the formation of immunogenic aggregates of insulin. The possible clinical consequences of these high levels of IAs remain to be evaluated because a low-glucose morning syndrome or severe insulin resistance with ketone bodies production have been reported in some cases. In conclusion, even if CSII and CPII may promote the development of circulating IAs, this increase does not lead to immunological insulin resistance, compared to that previously described with animal non-purified insulin preparations, and seems to have only marginal influence on blood glucose control or complications in most diabetic patients.

Treatment of diabetes mellitus using an external insulin pump: the state of the art

The aim of diabetes treatment is to achieve tight glucose control to avoid the development of chronic diabetic complications while reducing the frequency of hypoglycaemic episodes. Continuous subcutaneous insulin infusion (CSII) using an external pump is an intensive diabetes therapy recognized to improve metabolic control and glycaemic instability, and to reduce the frequency of severe hypoglycaemia. For years, the theoretical advantages of the insulin pump (constancy of basal delivery, adjustable basal rates, and low insulin depots allowing the reduction of glycaemic variability) have contributed to its reported superiority compared with multiple daily injections (MDI). However, insulin pump therapy is now challenged by new MDI regimens based on long-acting insulin analogues that could replace the use of CSII. As a consequence, health professionals now have to determine which patients are likely to benefit the most from CSII. Recently, several studies reported that children and adolescents, and patients whose blood glucose imbalance was initially the most pronounced with basal-bolus regimens, would particularly benefit from CSII. Other indications were also proposed in marginal clinical situations with highly selected patients in whom a significant improvement of blood glucose was demonstrated. Finally, the use of CSII in type 2 diabetic patients now appears to be a good alternative to the ineffective MDI regimens observed in some of these patients. However, past experience with CSII indicates that candidates for insulin pump therapy must be carefully selected and strongly motivated to improve their glucose control. Use of CSII also requires strict medical supervision by physicians and a regular programme of patient education by paramedical teams, to ensure optimal responsible use of this technique by healthcare professionals.

Implantable insulin pumps. A position statement about their clinical use

AIM

To review clinical use of implantable insulin pumps and to suggest indications for this therapy.

METHODS

The EVADIAC group performed a review of published reports on implantable insulin pumps for the last 15 years and analyzed its own centralized database. From this update, a position statement on indications of this therapy is drawn.

RESULTS

Published papers mostly report safety and effectiveness data from observational cumulated experiences of 15-350 patient-years. While HbA(1c) reduction does not reach statistical significance in all reported studies, improvement of blood glucose stability and reduction of severe hypoglycaemia appear as constant characteristics of this therapy. When compared to subcutaneous insulin therapy in randomized controlled studies, implantable pumps allow significantly reduced blood glucose fluctuations and improved quality of life in both type 1 and type 2 diabetic patients, and a significant weight decrease in type 2 diabetic patients. While the EVADIAC registry shows the reduced occurrence of pump-pocket complications thanks to preventive measures and a lower incidence of catheter obstructions following improvements of catheter design, underdelivery due to insulin aggregation in pumps remains a recurrent although reversible issue. Determinants of increased anti-insulin antibody production in some patients remain elusive but impact on blood glucose control is limited in most cases.

CONCLUSION

From analyzed data, the EVADIAC group states that implantable pumps can be safely indicated and provide metabolic improvements in type 1 diabetic patients who remain far from targeted HbA(1c) below 7% and/or experience large fluctuations of blood glucose including recurrent severe hypoglycaemia, in spite of intensive follow-up and education when treated by subcutaneous insulin.

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.

Biophysical delivery of peptides: applicability for cancer therapy

There is a current trend towards evaluation of molecular agents for treatment of a variety of ailments, including cancer. One class of such biomolecules is proteins, and their shortened versions, peptides. Use of peptidic entities has been hindered by poor bioavailability in vivo and the high cost involved in mass-producing these macromolecular drugs. The need for localized delivery is being met with the development of various biophysical means, which include devices and aids, mainly transdermal and invasive implants. In addition, various cell-based delivery modalities, which include the use of spore-forming bacteria and stem cells, are being explored. This review discusses these methods in turn, and examines ways by which these can be enhanced for peptide delivery to tumors.