Comparative Impact of Isolated Ultrafiltration and Hemodialysis on Fluid Distribution: A Bioimpedance Study

<b><i>Introduction:</i></b> Isolated ultrafiltration (IUF) is an alternative treatment for diuretic-resistant patients with fluid retention. Although hemodialysis (HD) predominantly decreases extracellular water (ECW), the impact of IUF on fluid distribution compared with HD remains unclear. <b><i>Methods:</i></b> We compared the effect of HD (<i>n</i> = 22) and IUF (<i>n</i> = 10) sessions on the body fluid status using a bioimpedance analysis device (InBody S10). <b><i>Results:</i></b> The total ultrafiltration volume was similar between HD and IUF (HD 2.5 ± 0.3 vs. ICF 2.1 ± 0.3 L/session, <i>p</i> = 0.196). The reduction rate of ECW was significantly higher than that of intracellular water (ICW) after HD (ECW −7.9% ± 0.8% vs. ICW −3.0% ± 0.9%, <i>p</i> &#x3c; 0.001) and IUF (ECW −5.8% ± 0.9% vs. ICW -3.6% ± 0.8%, <i>p</i> = 0.048). However, the change in the ratio of ECW to total body water in HD was significantly larger than that in IUF (HD −3.2% ± 0.3% vs. ICF −1.1% ± 0.4%, <i>p</i> &#x3c; 0.001). The reduction rates in serum tonicity (effective osmolality) were higher after HD than after IUF (HD −1.8% ± 0.5% vs. IUF −0.6% ± 0.2%, <i>p</i> = 0.052). Among the components of effective osmolality, the reduction rates of serum K⁺ and glucose levels after HD were significantly higher than those after IUF (serum K⁺: HD −30.5% ± 1.6% vs. IUF −0.5% ± 3.8%, <i>p</i> &#x3c; 0.001; serum glucose: HD −15.4% ± 5.0% vs. IUF 0.7% ± 4.8%, <i>p</i> = 0.026), while the serum Na⁺ level was slightly and similarly reduced (HD −0.8% ± 0.4% vs. IUF −0.8% ± 0.4%, <i>p</i> = 0.500). The reduction in the osmolal gap value (measured osmolality–calculated osmolarity) was significantly greater after HD sessions than after IUF sessions (HD −12.4 ± 1.4 vs. IUF 2.0 ± 1.0 mOsm/kg, <i>p</i> = 0.001). <b><i>Conclusion:</i></b> The extracellular fluid reduction effect of HD is stronger than that of IUF. The different changes in effective osmolality and osmolal gap after HD and IUF sessions may be related to the different effects of HD and IUF on fluid distribution.

Intoxication by Hand-Sanitizers and other Toxic Alcohols in a Low-Resource Setting: Two Case Reports

Toxic alcohol poisoning can be lethal if not identified early and treated appropriately. Toxic alcohol assays are often unavailable in low-resource setting, so clinicians have to infer a diagnosis based on suspicion, repeated evaluation and biochemical course. We report a case of toxic alcohol poisoning concealed by auto-intoxication with in-hospital hand sanitizer. The eventual appearance of a concurrent high anion gap prompted dialysis. In another case, a comatose patient presented with a high osmolal gap and a high anion gap. Incorrect a priori opinions caused us to defer dialysis and the patient died shortly afterwards. Clinicians should be aware that toxic alcohol poisoning can produce a confusing diagnostic picture with an insidious course, and that doctor delay can prove fatal.

Pseudohyponatremia and falsely increased serum osmolal gap caused by paraprotein in a patient with severe metabolic acidosis – a case study

Introduction: The aim of the study is to present a case study of a 63-year-old male with pseudohyponatremia, falsely increased serum osmolal gap and severe metabolic acidosis. Material and Methods: Venous whole blood (direct sodium selective electrode measurement) and serum (indirect sodium selective electrode measurement) were used to measure sodium concentration. Serum cholesterol, triacylglycerides and total protein were measured to confirm pseudohyponatremia. Base excess in extracellular fluid and serum bicarbonate concentrations were employed as markers of metabolic acidosis. Serum protein electrophoresis and free light chain analysis were used for the detection of paraproteins. Results: Venous whole blood acid base analysis showed a pH of 7.171, negative base excess in extracellular fluid of – 18.6 mmol/L and sodium concentration of 140 mmol/L. Serum test measurement revealed serum sodium concentration of 130 mmol/L, osmolal gap of 24 mmol/kg, creatinine concentration of 702 µmol/L, HCO3- concentration of 6.1 mmol/L and total protein concentration of 134.9 g/L. Serum paraprotein IgG kappa with a concentration of 86 g/L and a serum free light chains kappa/lambda ratio of 223.5, along with the final diagnosis of multiple myeloma were detected. Toxic alcohol ingestion was considered, both methanol and ethylene glycol tests were negative. Conclusions: High paraprotein concentrations in serum may lead to pseudohyponatremia when measured by indirect ion selective electrodes. Multiple myeloma frequently leads to renal failure with metabolic acidosis.

SUN-668 Elevated Osmolal Gap in Long-Term Complication of Type 2 Diabetes

Osmolal gap (OG) is the difference between the measured osmolality and calculated osmolality estimated by using the mathematical equation. Elevated OG indicates the presence of osmotically active particles undetected in the plasma of healthy individuals. Elevated OG has been observed in multiorgan trauma as a useful prognostic factor of patient survival [1, 2]. We hypothesized that elevated OG may occur in patients with type 2 diabetes (T2D) and may become a useful indicator of unmeasured endotoxins. One of the major mechanisms of this phenomenon may be non-enzymatic glycation of proteins in hyperglycemia, in which the osmotic active carbonyl compounds such as glyoxal, methylglyoxal, and 3-deoxyglucosone, are formed. Testing was performed for participants with T2D, aged 18 to 85. The osmolality measurement was performed with venous blood using the osmometer. The concentration of individual osmols (sodium, potassium, glucose, urea) was determined and on this basis, osmolality was calculated using the Dorwart-Chalmers formula: osmolality (mOsm/kg H2O) = 1.86 x [Na+] + glucose + urea + 9 (Dorwart, 1975). The clinical profile of patients was established based on history and physical examination (age, sex, age, duration of T2D, complications of T2D, HbA1c, LDL-cholesterol, triglyceride, BMI, coexisting diseases, medication). Data were analyzed using descriptive statistics. This study is currently ongoing, but preliminary data from the pilot study suggest an increased mean measured osmolality as well as elevated OG in patients with T2D compared to the reference values for healthy adults. These values differed depending on the type of long-term complications and the duration of the disease. In the pilot study, the highest OG was reported in diabetic retinopathy. A follow-up study with a larger sample may have a better ability to detect the statistical significance of the association of OG and complications of T2D. The association of the osmolal gap and complication of type 2 diabetes is poorly understood, and further investigation is warranted. References: [1] Inaba, H., Hirasawa, H., Mizuguchi, T. (1987), Serum Osmolality Gap In Postoperative Patients In Intensive Care. Lancet, 329 (8546): 1331-1335. [2] Hirasawa, H., Odaka, M., Sugai, T., Ohtake, Y., Inaba, H., Tabata, Y., Kobayashi, H. and Isono, K. (1988), Prognostic Value of Serum Osmolality Gap in Patients with Multiple Organ Failure Treated with Hemopurification. Artificial Organs, 12: 382-387.