Anion Gap (anion + gap)

Distribution by Scientific Domains


Selected Abstracts


Pathophysiology of ketoacidosis in Type 2 diabetes mellitus

DIABETIC MEDICINE, Issue 10 2005
P. Linfoot
Abstract Aims Despite an increasing number of reports of ketoacidosis in populations with Type 2 diabetes mellitus, the pathophysiology of the ketoacidosis in these patients is unclear. We therefore tested the roles of three possible mechanisms: elevated stress hormones, increased free fatty acids (FFA), and suppressed insulin secretion. Methods Forty-six patients who presented to the Emergency Department with decompensated diabetes (serum glucose > 22.2 mmol/l and/or ketoacid concentrations , 5 mmol/l), had blood sampled prior to insulin therapy. Three groups of subjects were studied: ketosis-prone Type 2 diabetes (KPDM2, n = 13) with ketoacidosis, non-ketosis-prone subjects with Type 2 diabetes (DM2, n = 15), and ketotic Type 1 diabetes (n = 18). Results All three groups had similar mean plasma glucose concentrations. The degree of ketoacidosis (plasma ketoacids, bicarbonate and anion gap) in Type 1 and 2 subjects was similar. Mean levels of counterregulatory hormones (glucagon, growth hormone, cortisol, epinephrine, norepinephrine), and FFA were not significantly different in DM2 and KPDM2 patients. In contrast, plasma C-peptide concentrations were approximately three-fold lower in KPDM2 vs. non-ketotic DM2 subjects (P = 0.0001). Type 1 ketotic subjects had significantly higher growth hormone (P = 0.024) and FFA (P < 0.002) and lower glucagon levels (P < 0.02) than DM2. Conclusions At the time of hospital presentation, the predominant mechanism for ketosis in KPDM2 is likely to be greater insulinopenia. [source]


Use of sodium concentration and anion gap to improve correlation between serum chloride and bicarbonate concentrations

JOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2006
Mark Feldman
Abstract Although most acid-base disorders cause opposite and equal changes in serum chloride and bicarbonate concentrations, this inverse relationship can be distorted by changes in the anion gap and/or water balance. Therefore, we examined the relationship between chloride and bicarbonate before and after adjusting for anion gap and serum sodium concentration. Patients with abnormal electrolytes were grouped by chloride and bicarbonate concentrations (low, normal, and high). Then, chloride and anion gap-adjusted bicarbonate were adjusted for water excess (or deficit), manifesting as hyponatremia (or hypernatremia), after which patients were reclassified. Classification by chloride and bicarbonate changed in 82% of the 135 patients after adjustment for anion gap and sodium. Serum chloride and bicarbonate were each low (concordant) in 23 patients, while 18 had discordant chlorides and bicarbonates (9 low/high, 9 high/low). After adjustments, chloride and bicarbonate were discordant in 40 patients (31 low/high, 9 high/low) and concordant in none. The correlation between serum chloride and bicarbonate improved from ,0.459 to ,0.998 after adjustments for sodium and anion gap. A very close inverse relationship between serum chloride and bicarbonate concentrations is commonly distorted by concomitant water disturbances and anion gap acidoses in internal medicine patients admitted with electrolyte disorders. J. Clin. Lab. Anal. 20:154,159, 2006. © 2006 Wiley-Liss, Inc. [source]


Assessment of acid-base status of cats with naturally occurring chronic renal failure

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 2 2003
J. Elliott
Metabolic acidosis is reported to be a common complication of feline chronic renal failure (CRF) but acid-base status of feline patients with this disease is rarely assessed by general practitioners. A cross-sectional study involving 59 cases of naturally occurring feline CRF was conducted to determine the prevalence of acid-base disturbances. Cases were categorised on the basis of their plasma creatinine concentrations as mild, moderate or severe. A group of 27 clinically healthy, age-matched cats was assessed for comparison. A low venous blood pH (<7·270) was found in 10 of the 19 severe cases (52·6 per cent), three of the 20 moderate cases (15 per cent) and none of the 20 mild cases. Acidaemia was associated with an increased anion gap contributed to by both low plasma bicarbonate and low chloride ion concentrations. Biochemical analysis of urine samples showed urine pH to decrease with increasing severity of renal failure. Urinary loss of bicarbonate was not associated with the occurrence of acidaemia and there was a tendency for urinary ammonium ion excretion to decrease as the severity of renal failure increased. Cats with naturally occurring CRF do not show plasma biochemical evidence of acid-base disturbances until the disease is advanced. [source]