Serum chloride

Low serum chloride and elevated serum bicarbonate levels indicate metabolic alkalosis. 

Huber C., Krause C., Werner T., Wolfbeis O.S., Serum chloride optical sensors based on dynamic quenching of the fluorescence of photo-immobilized lucigenin, Microchimica Acta 2003 142 245-253. 

Serum electrolytes can be altered secondary to respiratory alkalosis. Serum chloride is usually increased serum potassium, phosphorus, and ionized calcium are usually decreased. 

Children with heart disease often require high-dose diuretic therapy, which can lead to hypochloremic metabolic alkalosis. There are limited data on the safety of acetazolamide in the treatment of hypochloremic metabolic alkalosis in children. In 28 patients, median age 2 (range 0.3-20) months who took acetazolamide 5 mg/kg for 3 days, there were no adverse events (36). There was no significant difference in any electrolyte concentration, except for serum HC03, which fell from 36 to 31 mmol/1, and serum chloride, which rose from 91 to 95 mmol/1. There was no change in urine output. Acetazolamide appears to be safe in very young patients when given for 3 consecutive days. 

Wenk RE, Lustgarten JA, Pappas NJ, Levy RI, Jackson R. Serum chloride analysis, bromide detection, and the diagnosis of bromism. Am J Clin Path 1976 64 49-57. 

The pathogenesis of ketoacidosis is discussed in detail in Chapter 25. Ketoacids such as P-hydroxybutyrate and 2-oxoglutarate accumulate and represent the unmeasured anions. Accumulation of these ketone bodies causes a decrease in HCOJ, a normal or low serum chloride, and a liigh anion gap. Ketoacids also accumulate in states of starvation and alcoholic malnutrition. 

Serum chloride concentration is usually slightly increased. Serum ionized calcium, potassium, and phosphorus concentration may be decreased. 

The concentration of serum electrolytes may also be altered secondary to the development of respiratory alkalosis. The serum chloride concentration is usually slightly increased, and serum potassium concentration may be slightly decreased. Clinically significant hypokalemia can be a consequence of extreme respiratory alkalosis, although the effect is usually very small or negligible. Serum phosphorus concentration may decrease by as much as 1.5 to 2.0 mg/dL because of the shift of inorganic phosphate into cells. Reductions in the blood ionized calcium concentration may be partially responsible for symptoms such as muscle cramps and tetany. Approximately 50% of calcium is bound to albumin, and an increase in pH results in an increase in binding." ... 

The anion gap is calculated by subtracting the sum of the value for serum chloride and for the serum HCOs" content from the serum sodium concentration. If the gap is greater than normal, it suggests that acids such as the ketone bodies acetoacetate and p-hydroxybutyrate are present in the blood in increased amounts. 

A narrow anion gap may occur with an overdose by bromide or nitrate, both of which can increase the serum chloride level measured by some laboratory instmments. Also, high concentrations of lithium, calcium, and magnesium will narrow the anion gap due to lowering of the serum sodium concentration. 

IV. Diagnosis. Consider bromism in any confused or psychotic patient with a high serum chloride level and a low or negative anion gap. The serum chloride level is often falsely elevated owing to interference by bromide in the analytic test the degree of elevation varies with the instrument. 

Zheng and coworkers have employed a similar methodology and have demonstrated that PVC membranes doped with indium tetraphenylporphyrin show high relative sensitivity to nitrite ions.- Manganese and indium porphyrins immobilized in silicone by Paeng et al. have been used for the potentiometric analysis of serum chloride levels." ... 

A non-anion gap acidosis (hyperchloremic acidosis anion gap <16 mEq/L) is characterized by an acidosis where the anion gap is unchanged from the patient s baseline. This occurs as the decrease in serum bicarbonate is equaled by the rise in serum chloride [3]. Bicarbonate is typically lost from the gastrointestinal tract (i.e., diarrhea) or through the kidneys (i.e., renal tubular acidosis) [4]. Although a few metabolic disorders result in a non-anion gap acidosis (i.e., Fanconi-Bickel syndrome, OMIM 227810), a non-anion gap acidosis is typically not the result of an inborn error of metabolism. 

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