Hypoglycaemia in the adult

Detection of intact insulin analogues in post-mortem vitreous humour-Application to forensic toxicology casework

The application of proteomic techniques to forensic science widens the range of analytical capabilities available to forensic laboratories when answering complex toxicology problems. Currently, these techniques are underutilised in post-mortem toxicology because of the historic focus on smaller (<1,000 amu) drug molecules. Definitive confirmation of an insulin overdose by analysis of post-mortem biological matrices is rare and challenging, however can assist coronial investigations pertaining to accidental or intentional overdoses in both diabetic and nondiabetic populations. A semiautomated micro-solid phase extraction paired with mass spectrometry-based insulin methodology was developed and validated for routine use in a Forensic Coronial Toxicology Laboratory. This resulting work reports the first Australian cases where synthetic insulins were confirmed by mass spectrometry in the vitreous humour of Type 1 diabetics who intentionally or accidentally overdosed on their prescription medication glargine and aspart. The detection of glargine M1 in Case 1, aspart in Case 2 and glargine M1 was indicated in Case 3. This paper highlights advancements in forensic coronial toxicology and the promising potential of proteomic analysis in a forensic context.

Is insulin intoxication still the perfect crime? Analysis and interpretation of postmortem insulin: review and perspectives in forensic toxicology

Insulin is an anabolic hormone essential to glucose homeostasis. Insulin therapy, comprising human insulin (HI) or biosynthetic analogs, is critical for the management of type-1 diabetes and many of type-2 diabetes. However, medication error including non-adapted dose and confusion of insulin type, and misuse, such as massive self-administration or with criminal intent, can have lethal consequences. The aim of this paper is to review the state of knowledge of insulin analysis in biological samples and of the interpretation of insulin concentrations in the situation of insulin-related death investigations. Analytic aspects are considered, as quantification can be strongly impacted by methodology. Immunoanalysis, the historical technique, has a prominent role due to its sensitivity and ease of implementation. Recently, liquid chromatography coupled to mass spectrometry has provided indispensable selectivity in forensic contexts, distinguishing HI, analogs, and degradation products. We review the numerous antemortem (dose, associated pathology, injection-to-death interval, etc.) and postmortem parameters (in corpore degradation, in vitro degradation related to hemolysis, etc.) involved in the interpretation of insulin concentration. The interest and limitations of various alternative matrices providing a valuable complement to blood analysis are discussed. Vitreous humor is one of the most interesting, but the low diffusion of insulin in this matrix entails very low concentrations. Injection site analysis is relevant for identifying which type of insulin was administered. Muscle and renal cortex are matrices of particular interest, although additional studies are required. A table containing most case reports of fatal insulin poisoning published, with analytical data, completes this review. A logic diagram is proposed to highlight analytical issues and the main parameters to be considered for the interpretation of blood concentrations. Finally, it remains a challenge to provide reliable biological data and solid interpretation in the context of death related to insulin overdose. However, the progress of analytical tools is making the "perfect crime" ever more difficult to commit.

Verification of glycemic profiles using continuous glucose monitoring: cases with steroid use, liver cirrhosis, enteral nutrition, or late dumping syndrome

Glycemic control is often difficult to achieve in patients with diabetes, especially in the presence of comorbid diseases or conditions such as steroid-use or liver cirrhosis, or in patients receiving enteral nutrition. Moreover, reactive hypoglycemia due to late dumping syndrome in people having undergone gastrectomy is also a matter of concern. Empirically and theoretically, the typical glycemic profiles associated with these conditions have been determined; however, what actually happens during a 24-h span is still somewhat obscure. In order to verify and provide information about the 24-h glycemic profiles associated with these conditions, 8 patients with the 4 above-mentioned conditions were monitored using a continuous glucose monitoring system (CGMS). For all 8 patients, CGMS provided detailed information regarding the 24-h glycemic profiles. The CGM results showed typical glycemic patterns for each condition, and we were moreover able to observe the effects of various practical treatments. Based on these cases, we conclude that the CGMS is highly useful for determining the glycemic patterns of patients with the aforementioned conditions in a practical setting; and this system may be used to monitor the treatment success of such cases.

Concurrent Therapy with a Low-carbohydrate Diet and Miglitol Remarkably Improved the Postprandial Blood Glucose and Insulin Levels in a Patient with Reactive Hypoglycemia due to Late Dumping Syndrome

Reactive hypoglycemia induced by late dumping syndrome is often observed after gastrectomy. However, no effective therapy has yet been fully established. We herein describe a case in which concurrent therapy with a low-carbohydrate diet using low-glycemic-index food and an alpha-glucosidase inhibitor, miglitol, very effectively ameliorated the postprandial fluctuations in the blood glucose and plasma insulin levels in a patient with reactive hypoglycemia due to late dumping syndrome following total gastrectomy. The administration of miglitol under a low-carbohydrate diet using low-glycemic-index food may therefore be an ideal treatment for reactive hypoglycemia due to late dumping syndrome.

Quality and reliability of current malaria diagnostic methods

Malaria is a life threatening disease with a major impact on global health. The WHO declared an early diagnosis as one of the most important steps to fight the disease. The quality and the reliability of test results depend on the diagnostic tools used. Not every test meets the needs in every situation. PCR tests have the best sensitivity and specifity but are not as rapid as other tests and also due to the costs not available everywhere. The 'gold standard' method is to check stained blood slides, thick films require experienced persons to obtain correct results. So-called rapid tests are only additional tools no matter whether they are based on the detection of antigens, enzymes or plasmodial DNA by fluorescent staining. Some other blood bound markers may also provide a hint but are no sufficient tool for malaria diagnosis.

Successful treatment of reactive hypoglycemia secondary to late dumping syndrome using miglitol

We herein describe a 59-year-old woman who had undergone a total gastrectomy for gastric carcinoma and suffered from postprandial hypoglycemia characterized by a loss of consciousness and spasms. She was diagnosed with reactive hypoglycemia and treated with nutrition therapy, but the frequency and severity of the hypoglycemic episodes did not decrease. She was subsequently treated successfully with miglitol, an alpha-glucosidase inhibitor (α-GI) taken twice a day; other α-GIs (acarbose and voglibose) were not effective. In conclusion, the administration of miglitol was effective for preventing reactive hypoglycemia secondary to late dumping syndrome.

Idiopathic reactive hypoglycaemia - prevalence and effect of fibre on glucose excursions

BACKGROUND

Idiopathic reactive hypoglycaemia (IRH) is a condition characterized by aggravated postprandial glucose excursions in otherwise healthy individuals. We investigated its prevalence and the impact of fibre diet supplementation.

METHODS

First, IRH prevalence was assessed in 362 subjects without a diagnosis of abnormal glucose metabolism through an oral glucose tolerance test (OGTT). IRH was defined by 1 h- or 2 h-glucose ≤3.9 mmol/L or 1 h- or 2 h-glucose < fasting glucose. Second, in a cross-over trial we evaluated effects of 2 weeks with, and without, 20 g fibre (fructose- oligosaccharides) diet supplementation in subjects with IRH. At the end of each 2-week cycle we analysed fasting biomarker levels and conducted a 4 h-OGTT.

RESULTS

IRH was found in 12.4% and a normal glucose tolerance in 56.4% of the participants. The IRH group was characterized by higher fasting (5.3 vs. 5.2 mmol/L, p < 0.05) but lower 2 h- (4.4 vs. 6.5 mmol/L, p < 0.01) glucose levels, whereas age (68 ± 10 vs. 70 ± 9 years) and BMI (24.7 ± 3.3 vs 25.0 ± 3.5 kg/m(2)) were similar. The 2-week fibre diet-supplementation (n = 12, age 56 ± 8 years, 6 females, BMI 25.0 ± 2.9 kg/m(2)) improved both the reactive glucose pattern during the 4 h-OGTT (significantly increased late-onset glucose nadirs and reduced the frequency of glucose ≤3.9 mmol/L [21 to 11, p = 0.04]) and reduced fasting plasma glucose (5.4 ± 0.6 to 5.1 ± 0.5 [p < 0.05]) and total cholesterol (5.3 ± 1.1 to 4.9 ± 1.1 mmol/L [p < 0.04]).

CONCLUSIONS

A reactive glucose pattern following intake of a high glycaemic load is relatively prevalent and this phenomenon could be modulated by dietary fibre supplementation.

A case of haemangiopericytoma-associated hypoglycaemia: Beneficial effect of treatment with radiotherapy

A 72-year-old lady presented with recurrent hypoglycaemia and a large pelvic mass. Hypoglycaemia was accompanied by undetectable serum insulin and c-peptide and high insulin-like growth factor II (IGFII) to IGFI ratio. She had undergone successful resection of a large bladder haemangiopericytoma 7 years earlier. A core biopsy was performed, and histology confirmed the recurrence of the haemangiopericytoma. Local palliative radiotherapy resulted in the reduction of IGFII level and IGFII to IGFI ratio and increased insulin, c-peptide and growth hormone (GH) level with long-term amelioration of hypoglycaemic episodes. Clinically and biochemically, radiotherapy was more effective than GH therapy.

The biochemical investigation of cases of hypoglycaemia: an assessment of the clinical effectiveness of analytical services

AIM

To assess the extent to which biochemical analytical services contribute to the diagnosis and management of clinical cases of hypoglycaemia.

METHODS

All cases of confirmed hypoglycaemia, referred during a six month period, were included in the survey. Questionnaires were sent to each referring laboratory requesting information on the clinical progress and current status of the patient.

RESULTS

The level of influence exerted by analytical data was assigned in each case and those with similar outcomes combined. Identifiable case groups were: (1) Results not recorded in the patients' notes (15.7%). (2) Inappropriate requesting of insulin and C peptide measurements in cases of diabetes (11.4%). (3) Patient died soon after investigation (20.0%). (4) Patient recovered spontaneously (17.1%). (5) Patient received effective medical or surgical treatment (12.9%). (6) Patient awaiting or not requiring pathology based treatment (31.4%). (7) Inconclusive outcome prompting further investigation (5.7%).

CONCLUSIONS

Within the timescale of the survey (approximately 12 months), positive progress had been made towards diagnosis and subsequent treatment in only 10% of cases. Another 30% were either awaiting some form of treatment or further diagnostic tests. The remaining 60% did not appear to benefit in any way from the biochemical investigations.

Hypoglycemia

Except in diabetic patients receiving insulin or sulfonylureas, hypoglycemia is a rare disorder. It is identified by modified Whipple's criteria consisting of neuroglycopenic symptoms, a blood glucose level equal to or less than 40 mg/dL, and relief of symptoms by glucose use. The sources of the body glucose are dietary intake, glycogenolysis, and [figure: see text] gluconeogenesis. The metabolism of glucose involves oxidation and storage as glycogen or fat. Causes of hypoglycemia include medications or toxins capable of decreasing blood glucose, disorders associated with fasting hypoglycemia, and postprandial hypoglycemic disorders. The most common type of hypoglycemia is insulin-induced hypoglycemia in diabetics. Insulinoma is rare; however, it is the most common hormone-secreting islet cell tumor. The diagnosis is made by the occurrence of hypoglycemia in the presence of symptoms of neuroglycopenia and inappropriately high levels of insulin and C-peptide. In hospitalized patients, the diagnosis is best made by prolonged fast. Most insulinomas are small and require invasive methods for precise localization. In surreptitious insulin use, hypoglycemia is associated with low plasma C-peptide. Postprandial hypoglycemia occurs in response to feeding and is generally caused by excessive insulin effect. It is seen in patients with postgastric surgery and rarely in early diabetes mellitus. Idiopathic postprandial hypoglycemia is rare and seems to be caused by subtle abnormalities of insulin response to food. Treatment of postprandial hypoglycemia consists of frequent small meals, with deletion of refined carbohydrate and increased protein intake. Primary treatment of insulinoma is surgical resection of the tumor.

Severe mitral stenosis in a parturient with congestive cardiac failure and hypoglycaemia

We report a case of maternal mortality in a 34-year-old multipara who presented at the 35th week of gestation with severe hypoglycaemia. She had no history of diabetes mellitus. This episode was a prelude to catastrophic and refractory congestive cardiac failure due to previously undiagnosed severe mitral stenosis. The rapid cardiovascular deterioration initially appeared to be consistent with amniotic fluid embolism. She also developed deranged liver function with disseminated intravascular coagulation, which mimicked acute fatty liver of pregnancy. The problems of diagnosis and management are discussed. Unfortunately the patient died before mitral valvular commissurotomy could be effected.

Nesidioblastosis in an elderly patient

We report an 84-year-old woman with hypoglycaemia and hyperinsulinaemia caused by diffuse nesidioblastosis. This is the oldest case of nesidioblastosis so far recorded. The case illustrates some of the difficulties in diagnosing inappropriate hyperinsulinaemia and the benefits of surgery, even in old age. Hypoglycaemia should be considered in patients with variable mental function.