Hypochloremia

Template:Short description Template:Infobox medical condition (new) Hypochloremia (or Hypochloraemia) is an electrolyte disturbance in which there is an abnormally low level of the chloride ion in the blood. Normal serum range for chloride is 97 to 107 mmol/L with levels less than 96 mmol/L defining hypochloremia.<ref>Template:Cite journal</ref>

Hypochloremia can contribute to metabolic alkalosis. Patients with mild hypochloremia may be asymptomatic. In significant chloride depletion and the resulting alkalosis, symptoms may include neuromuscular irritability, such as muscle cramps, twitching, and, in severe cases, seizures.<ref name=Sagar2024>Template:Cite journal</ref>

Treatment involves diagnosing the underlying cause. Mild hypochloremia may be corrected by salt intake. For more severe hypochloremia, IV fluids may be given.<ref name=SciDir>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

It rarely occurs in the absence of other abnormalities. It is sometimes associated with hypoventilation.<ref name="pmid3764530">Template:Cite journal</ref> It can be associated with chronic respiratory acidosis.<ref name="pmid13611033">Template:Cite journal</ref> If it occurs together with metabolic alkalosis (decreased blood acidity) it is often due to vomiting.<ref name=Berend2012>Template:Cite journal</ref> It is usually the result of hyponatremia or elevated bicarbonate concentration. It occurs in cystic fibrosis.<ref name=Scurati2014>Template:Cite journal</ref>

Causes

Gastrointestinal causes

• Gastric fluid loss – loss of hydrochloric acid from the stomach due to severe vomiting or nasogastric suction tube.<ref name=Berend2012/>
• Congenital chloride diarrhea – rare autosomal recessive disease characterized by persistent, lifelong, watery diarrhea with high fecal chloride concentration.<ref name="pmid1694648">Template:Cite journal</ref>

Renal causes

• Diuretic therapy – Thiazide diuretics and loop diuretics like furosemide inhibit chloride reabsorption causing hypochloremia and metabolic alkalosis. Thiazides block NCC and furosemide blocks NKCC2.<ref name=Berend2012/>
• Chronic respiratory acidosis – Compensatory reabsorption of bicarbonate in exchange for chloride.<ref name=pmid13611033/><ref name=Berend2012/>
• Bartter syndrome – Chloride wasting due to defective NKCC2 Symptoms similar to loop diuretic therapy like furosemide.<ref name=Berend2012/>
• Gitelman syndrome – Chloride wasting due to defective NCC. Symptoms similar to thiazide diuretic therapy.<ref name=Berend2012/>

Other causes

• Cystic fibrosis – Loss of chloride through excessive sweating due to defective chloride transport.<ref name=Scurati2014/>
• Excessive bicarbonate administration – Can dilute serum chloride and shift acid-base balance.<ref name=Sagar2024/>