Hypokalemia is a common electrolyte disturbance, especially in hospitalized patients. It can have various causes, including endocrine ones. Sometimes, hypokalemia requires urgent medical attention. The aim of this review is to present updated information regarding: (1) the definition and prevalence of hypokalemia, (2) the physiology of potassium homeostasis, (3) the various causes leading to hypokalemia, (4) the diagnostic steps for the assessment of hypokalemia and (5) the appropriate treatment of hypokalemia depending on the cause. Practical algorithms for the optimal diagnostic, treatment and follow-up strategy are presented, while an individualized approach is emphasized.
Efstratios Kardalas, Stavroula A Paschou, Panagiotis Anagnostis, Giovanna Muscogiuri, Gerasimos Siasos and Andromachi Vryonidou
Stavroula A Paschou, Nektaria Papadopoulou-Marketou, George P Chrousos and Christina Kanaka-Gantenbein
Type 1 diabetes mellitus (T1DM) results from the autoimmune destruction of β cells of the endocrine pancreas. Pathogenesis of T1DM is different from that of type 2 diabetes mellitus, where both insulin resistance and reduced secretion of insulin by the β cells play a synergistic role. We will present genetic, environmental and immunologic factors that destroy β cells of the endocrine pancreas and lead to insulin deficiency. The process of autoimmune destruction takes place in genetically susceptible individuals under the triggering effect of one or more environmental factors and usually progresses over a period of many months to years, during which period patients are asymptomatic and euglycemic, but positive for relevant autoantibodies. Symptomatic hyperglycemia and frank diabetes occur after a long latency period, which reflects the large percentage of β cells that need to be destroyed before overt diabetes become evident.
Stavroula A Paschou, Eleni Palioura, Dimitrios Ioannidis, Panagiotis Anagnostis, Argyro Panagiotakou, Vasiliki Loi, Georgios Karageorgos, Dimitrios G Goulis and Andromachi Vryonidou
The aim of this study was to investigate the impact of adrenal hyperandrogenism on insulin resistance and lipid profile in women with polycystic ovary syndrome (PCOS).
Patients and methods
We studied 372 women with PCOS according to the NIH criteria. 232 age- and BMI-matched women served as controls in order to define adrenal hyperandrogenism (DHEA-S >95th percentile). Then, patients with PCOS were classified into two groups: with adrenal hyperandrogenism (PCOS-AH, n = 108) and without adrenal hyperandrogenism (PCOS-NAH, n = 264). Anthropometric measurements were recorded. Fasting plasma glucose, insulin, lipid profile, sex hormone-binding globulin (SHBG) and androgen (TT, Δ4A, DHEA-S) concentrations were assessed. Free androgen index (FAI) and homeostatic model assessment-insulin resistance (HOMA-IR) index were calculated.
Women with PCOS-AH were younger than PCOS-NAH (P < 0.001), but did not differ in the degree and type of obesity. No differences were found in HOMA-IR, total cholesterol, HDL-c, LDL-c and triglyceride concentrations (in all comparisons, P > 0.05). These metabolic parameters did not differ between the two groups even after correction for age. Women with PCOS-AH had lower SHBG (29.2 ± 13.8 vs 32.4 ± 11.8 nmol/L, P = 0.025) and higher TT (1.0 ± 0.2 vs 0.8 ± 0.4 ng/mL, P = 0.05) and Δ4A (3.9 ± 1.2 vs 3.4 ± 1.0 ng/mL, P = 0.007) concentrations, as well as FAI (14.1 ± 8.0 vs 10.2 ± 5.0, P < 0.001). These results were confirmed by a multiple regression analysis model in which adrenal hyperandrogenism was negatively associated with age (P < 0.001) and SHBG concentrations (P = 0.02), but not with any metabolic parameter.
Women with PCOS and adrenal hyperandrogenism do not exhibit any deterioration in insulin resistance and lipid profile despite the higher degree of total androgens.