Electrolyte Economy and Its Hormonal Regulation in Congenital Chloride Diarrhea

Abstract

Summary SUBJECTSThe economy of CI-, K+, and Mg++, extracellular volume (ECV) and plasma volume, and the role of hyperreninemia and hyperaldosteronism were explored in 22 patients with congenital chloride diarrhea. Stool volume was in significant correlation with its CI-, Na+ and K+ content, the correlation being significantly better with CI-content than with the Na+ content. Low fecal CI-concentrations were seen in chronic hypochloremic contraction, but acute episodes did not cause reduction of fecal CI-concentration from the basal level of 140-150 mmoll liter. The adequate condition (defied as normal serum electrolyte concentrations and blood pH, and presence of CI-in urine) was associated with high total exchangeable C1-and ECV. This excess CI-and ECV roughly equalled the high daily fecal amount of CI-and volume. Reduced ECV was accompanied bv high renin activities and hyperaldosteronism, but in theadequate condition these were normal. Hvperaldosteronism caused a decrease in urinary Na+-K+ ratio-and, after the age of 2-6 months, in the fecal Na+-K+ ratio. Total exchangeable K+ was normal in the adequate condition. No Mg++ depletion was present, although the patients lack Mg++ substitution. The adequate condition could be maintained with an oral supplement of NaCI, KC1 and water.Twenty-two patients, aged 0.5-14.5 years (18), were studied. Their early long term substitution was with a 0.15-0.3 M water solution of KC1 only, the dose (45-204 mmol/m2/24 hr) being adjusted to maintain normal serum electrolyte concentrations. Several episodes of acute dehydration had occurred lasting up to a week during the first years of life, but the subsequent clinical condition of the patients had been good. They passed a constantly Cl--free urine and tended to be slightly alkalotic.Five years ago the therapy was changed to a 0.15-0.3 M NaCl + KC1 solution with the molar ratio of the salts individually varying from 3: 1 to 1: 1. The dose was 60-216 mmol/m2 daily and was adjusted to maintain chloriduria in addition to normal serum electrolyte concentrations and blood pH. Such a state will be referred to as the adequate condition. The recordings of low serum electrolyte concentrations and alkalosis in this study were obtained from observations during acute exacerbations of the diarrhea, due to respiratory and gastrointestinal infections, and from observations in our early patients. METHODS SpeculationSerum electrolyte concentrations and blood pH were measured according to standard methods. Urinary and fecal electroHyperreninemi% h~~eraldosteronism, and h~~o k a l e m i c a k a -lyte excretion was always measured from 24-hr collections. losis in congenital chloride diarrhea (CCD) are secondary to F~~ measurement of total exchangeable (-1-(TECI-), 0.3 hypochloremic ECV contraction and can be completely cor-p~i / k g of 36C1, NaCl solution ( > 3 mCilg ~1 -) was injected rected with adequate substitution. Mg++ depletion does not intravenously with 5 % glucose. Urines and stools were collected play a Part in CCD. The to h~~eraldosteron-...

Congenital Chloride Diarrhea: Is it a Common Disorder in Saudi Arabia?

“…If the fluid and electrolyte deficits are not replaced, extracellular volume contraction develops, resulting in secondary hyperaldosteronism and hyperreninemia. 11 The hyponatremia is corrected by renal absorption of Na + in exchange for K + ; the net outcome is hypokalemic hypochloremic metabolic alkalosis and high fecal losses of fluid, Cl -, Na + and K + . The finding of high fecal chloride (Cl ->90 mmol/L) is diagnostic of CCD.…”

“…The finding of high fecal chloride (Cl ->90 mmol/L) is diagnostic of CCD. 11 Fecal CI -greater than the sum of fecal Na + and K + is considered pathognomonic of CCD. The exceptions are neonates and patients with severe hypovolemia.…”

A case of congenital chloride diarrhea: information obtained through long-term follow-up with reduced electrolyte substitution

“…Generally, the hypokalemia in CCD has been ascribed to excessive potassium wastage due to hyperaldosteronism in addition to diarrhea [10]. In our patient, however, hypokalemia persisted even when aldosterone excretion was suppressed to normal levels.…”

Congenital chloride diarrhea misdiagnosed as Bartter syndrome

“…After performing urine Clm easurement, the study of fecal electrolytes is needed to confirm the diagnosis of CLD. It is also worth remembering that fecal Cl¯may be low, even 40 mmol/L, in untreated CLD associated with severe dehydration (11). The history of "no diarrhea" in our case was thus based on severe dehydration.…”

“…As both CLD and Bartter syndrome are associated with hypokalemic metabolic alkalosis, each of these two diseases should be kept in mind in the differential diagnostics of the other. The si-tes of the basic defect, intestinal Cl¯/HCO 3¯e xchange defect in CLD and renal Na + -K + -2Cl¯trans-porter defect in Bartter syndrome (11), are different. Therefore, Cl¯is lost into stools in CLD and into the urine in Bartter syndrome, making differential diagnostics possible independent of similar hypokalemic metabolic alkalosis.…”