Is a Priming Dose of Insulin Necessary in a Low-Dose Insulin Protocol for the Treatment of Diabetic Ketoacidosis?

OBJECTIVE—The purpose of this study was to assess the efficacy of an insulin priming dose with a continuous insulin infusion versus two continuous infusions without a priming dose.RESEARCH DESIGN AND METHODS—This prospective randomized protocol used three insulin therapy methods: 1) load group using a priming dose of 0.07 units of regular insulin per kg body weight followed by a dose of 0.07 unit · kg⁻¹ · h⁻¹ i.v. in 12 patients with diabetic ketoacidosis (DKA); 2) no load group using an infusion of regular insulin of 0.07 unit · kg body weight⁻¹ · h⁻¹ without a loading dose in 12 patients with DKA, and 3) twice no load group using an infusion of regular insulin of 0.14 · kg⁻¹ · h⁻¹ without a loading dose in 13 patients with DKA. Outcome was based on the effects of insulin therapy on biochemical and hormonal changes during treatment and recovery of DKA.RESULTS—The load group reached a peak in free insulin value (460 μU/ml) within 5 min and plateaued at 88 μU/ml in 60 min. The twice no load group reached a peak (200 μU/ml) at 45 min. The no load group reached a peak (60 μU/ml) in 60–120 min. Five patients in the no load group required supplemental insulin doses to decrease initial glucose levels by 10%; patients in the twice no load and load groups did not. Except for these differences, times to reach glucose ≤250 mg/dl, pH ≥7.3, and HCO₃⁻ ≥15 mEq/l did not differ significantly among the three groups.CONCLUSIONS—A priming dose in low-dose insulin therapy in patients with DKA is unnecessary if an adequate dose of regular insulin of 0.14 unit · kg body weight⁻¹ · h⁻¹ (about 10 units/h in a 70-kg patient) is given.Although positive therapeutic responses to low-dose insulin therapy have been established in adult patients with diabetic ketoacidosis (DKA) (1–8), none of these studies and guidelines for the treatment of DKA, including the American Diabetes Association (ADA) Consensus and Position Statements, has ever assessed or addressed the use of a continuous insulin infusion without a loading dose of insulin (9). In the current study, we used a dose of 0.14 unit · kg⁻¹ · h⁻¹ without a loading dose instead of the recommended 0.1 unit · kg⁻¹ · h⁻¹ with a loading dose. This insulin regimen was chosen because one study in a pediatric population used a dosing regimen of 0.1 unit · kg⁻¹ · h⁻¹ without a loading dose that resulted in a total plasma insulin level of 50–60 μU/ml (10). This level proved to be too low for optimal suppression of hepatic glucose output and optimal glucose uptake (11). In addition, bolus doses of insulin may result in hypokalemia as well as other undesirable effects (12), especially when used in a routine hospital setting.The efficacy of low-dose insulin without a priming dose has not been established in a prospective randomized study (13). Thus, the following questions have remained unanswered in the treatment of DKA: 1) Is an insulin bolus needed before a continuous insulin infusion? 2) What is the optimal insulin infusion rate if a bolus dose is not used? and 3) What is the dose response of continuous insulin infusion used alone in regard to decremental changes in glucose, metabolic parameters, cortisol, and free fatty acids (FFAs)? Therefore, we evaluated responses to three low-dose insulin regimens in 37 consecutive patients with DKA in a prospective randomized fashion to address these issues. Changes in plasma free insulin, serum potassium levels, and outcome recovery measures were assessed using a higher infusion dose (0.14 unit · kg⁻¹ · h⁻¹ without a bolus dose) compared with a lower infusion dose (0.07 unit · kg⁻¹ · h⁻¹) with and without a loading dose (0.07 unit/kg) of insulin.     

Hyperglycemia: an independent marker of in-hospital mortality in patients with undiagnosed diabetes

Admission hyperglycemia has been associated with increased hospital mortality in critically ill patients; however, it is not known whether hyperglycemia in patients admitted to general hospital wards is associated with poor outcome. The aim of this study was to determine the prevalence of in-hospital hyperglycemia and determine the survival and functional outcome of patients with hyperglycemia with and without a history of diabetes. We reviewed the medical records of 2030 consecutive adult patients admitted to Georgia Baptist Medical Center, a community teaching hospital in downtown Atlanta, GA, from July 1, 1998, to October 20, 1998. New hyperglycemia was defined as an admission or in-hospital fasting glucose level of 126 mg/dl (7 mmol/liter) or more or a random blood glucose level of 200 mg/dl (11.1 mmol/liter) or more on 2 or more determinations. Hyperglycemia was present in 38% of patients admitted to the hospital, of whom 26% had a known history of diabetes, and 12% had no history of diabetes before the admission. Newly discovered hyperglycemia was associated with higher in-hospital mortality rate (16%) compared with those patients with a prior history of diabetes (3%) and subjects with normoglycemia (1.7%; both P < 0.01). In addition, new hyperglycemic patients had a longer length of hospital stay, a higher admission rate to an intensive care unit, and were less likely to be discharged to home, frequently requiring transfer to a transitional care unit or nursing home facility. Our results indicate that in-hospital hyperglycemia is a common finding and represents an important marker of poor clinical outcome and mortality in patients with and without a history of diabetes. Patients with newly diagnosed hyperglycemia had a significantly higher mortality rate and a lower functional outcome than patients with a known history of diabetes or normoglycemia.     

Diabetic Ketoacidosis

Diabetic ketoacidosis (DKA) is the most common hyperglycemic emergency in patients with diabetes mellitus. DKA most often occurs in patients with type 1 diabetes, but patients with type 2 diabetes are susceptible to DKA under stressful conditions, such as trauma, surgery, or infections. DKA is reported to be responsible for more than 100 000 hospital admissions per year in the US, and accounts for 4-9% of all hospital discharge summaries among patients with diabetes. Treatment of patients with DKA uses significant healthcare resources and accounts for 1 out of every 4 healthcare dollars spent on direct medical care for adult patients with type 1 diabetes in the US. Recent studies using standardized written guidelines for therapy have demonstrated a mortality rate of less than 5%, with higher mortality rates observed in elderly patients and those with concomitant life-threatening illnesses. Worldwide, infection is the most common precipitating cause for DKA, occurring in 30-50% of cases. Urinary tract infection and pneumonia account for the majority of infections. Other precipitating causes are intercurrent illnesses (i.e., surgery, trauma, myocardial ischemia, pancreatitis), psychological stress, and non-compliance with insulin therapy. The triad of uncontrolled hyperglycemia, metabolic acidosis and increased total body ketone concentration characterizes DKA. These metabolic derangements result from the combination of absolute or relative insulin deficiency and increased levels of counter-regulatory hormones (glucagon, catecholamines, cortisol, and growth hormone). Successful treatment of DKA requires frequent monitoring of patients, correction of hypovolemia and hyperglycemia, replacement of electrolyte losses, and careful search for the precipitating cause. Since the majority of DKA cases occur in patients with a known history of diabetes, this acute metabolic complication should be largely preventable through early detection, and by the education of patients, healthcare professionals, and the general public. The frequency of hospitalizations for DKA has been reduced following diabetes education programs, improved follow-up care, and access to medical advice. Novel approaches to patient education incorporating a variety of healthcare beliefs and socioeconomic issues are critical to an effective prevention program.     

Osteoprotegerin: A novel biomarker for inflammatory bowel disease and gastrointestinal carcinoma

Osteoprotegerin (OPG) is a member of the tumor necrosis factor receptor superfamily of proteins. Although initial data illustrated the key role that OPG plays in bone turnover, numerous recent reports indicate that OPG is also an important factor in inflammatory pathways and tumor cell survival. OPG contributes directly to inflammatory processes and has been evaluated as a novel non‐invasive biomarker of gut inflammation. Furthermore, OPG affects cell turn‐over, differentiation, death, and survival via extracellular pathways, correlating with worse prognosis in inflammatory bowel diseases and several gastrointestinal carcinomas. It is now clear that OPG has multiple functions and characteristics. This review gives an overview of OPG, highlights its roles in different extracellular pathways, and outlines how OPG could be used as a novel non‐invasive biological marker in inflammatory bowel diseases and gastrointestinal carcinomas.     

The value of flow cytometric analysis of platelet glycoprotein expression of CD34+ cells measured under conditions that prevent P- selectin-mediated binding of platelets

In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant.     

Frequent ongoing T-cell receptor rearrangements in childhood B- precursor acute lymphoblastic leukemia: implications for monitoring minimal residual disease

Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.     

Does syndrome X exist in hypertensive elderly persons with impaired glycemic control?

BACKGROUND: This report focuses on the glycemic state in relation to insulin and lipid levels of a cohort of elderly hypertensive persons to estimate the prevalence of syndrome X. METHODS: A cross-sectional study was performed at the University of Tennessee, Memphis, and the General Clinical Research Center (GCRC) on 95 participants in the Trial of Nonpharmacologic Interventions in the Elderly (TONE) study who agreed to participate in an ancillary study. A standard oral glucose tolerance test (OGTT) with insulin and C-peptide levels and a fasting lipid profile were obtained. RESULTS: In this sample of healthy elderly participants with hypertension who were taking an antihypertensive medication, 43 (45.3%) had normal glucose tolerance (NGT), 41 (43.2%) had impaired glucose tolerance (IGT), and 11 (11.6%) had undiagnosed non-insulin-dependent diabetes mellitus (NIDDM). Fasting hyperinsulinemia occurred in only one participant, who was in the IGT group. Hypertriglyceridemia and low high density lipoprotein (HDL) occurred in four persons, none of whom had hyperinsulinemia. Persons in the NIDDM and IGT groups had decreased beta cell function compared to persons in the NGT group, but did not have increased peripheral insulin resistance as estimated from the OGTT data. CONCLUSIONS: Our data demonstrated that in this cohort of elderly hypertensive participants with a high prevalence of central obesity, impaired glycemic control was common, but was not associated with fasting hyperinsulinemia or peripheral insulin resistance. Furthermore, we conclude that syndrome X essentially did not occur in these participants and postulate that the primary etiology for their impaired glycemic control is beta cell dysfunction. Further research is needed to elucidate these relationships.