Excess Chloride in the Blood in Dogs

Causes of hyperchloremia in dogs can range from something as minor as dehydration (usually at the hand of persistent diarrhea or vomiting) to more major conditions, such as kidney disease and Cushing’s disease. Treatment specific to hyperchloremia focuses on removing the cause of the excess chloride, as well as administration of sodium bicarbonate. If hyperchloremia is the only problem, or the underlying cause is minor, recovery should be rapid and complete.

Hyperchloremia refers to an excess concentration of chloride in the blood. This is typically caused by changes in free water/electrolyte-rich fluids or acid-base disturbances in the body. Depending on the reason for the condition, symptoms, treatment, and recovery can vary.

Symptoms of hyperchloremia vary depending on the associated causes. Symptoms of artifactual hyperchloremia relate to free water deficit, while symptoms of corrected hyperchloremia are often related to metabolic acidosis (an excess of acid in the body).  

• Gastrointestinal irritation
• Anorexia
• Weight loss
• Lethargy
• Persistent Hyperventilation
• Excessive thirst

Types

Artifactual

• Artifactual hyperchloremia occurs when there are deficits in the body’s free water or lower osmotic pressure in urine. Examples of conditions where artifactual hyperchloremia is present are hypernatremia (an electrolyte problem in which the total body water decreases relative to the electrolyte levels) and diabetes insipidus (a rare form of diabetes caused by deficiency of the pituitary hormone vasopressin).

Acid disturbance

• Acid-base disturbances can result from excessive intake or decreased output of chloride. This can be associated with diarrhea, therapies of chloride administration, salt poisoning, renal failure, renal tubular acidosis, hypoadrenocorticism, diabetes mellitus, and chronic respiratory alkalosis.

• Dehydration
• Diarrhea
• Vomiting
• Fever
• Excessive exposure to heat
• Large doses of diuretics
• Excessive intake of potassium chloride
• Acidity disruptions
• Hyperventilation
• Chronic kidney disease
• Poorly controlled diabetes
• Cushing’s disease
• Excessive intake of potassium bromide (used to control epilepsy)
• Excessive intake of ammonium chloride (used to increase urine acidity)
• Corticosteroids (hormone supplements for the adrenal cortex)
• NSAIDs (nonsteroidal anti-inflammatory drugs)

Hyperchloremia is a condition in which chloride levels in the blood are greater than the normal concentration of 107 to 113 mEq/L. Chloride is an electrolyte that typically mirrors sodium levels in the blood, since it has a 1:1 ratio with sodium. Because of this relationship, sodium and chloride should always be analyzed together. Changes in free water and/or electrolyte-rich fluids will change sodium and chloride concentrations proportionally. Disproportional changes in chloride, alternatively, are the result of an acid-base disturbance. To determine which is the cause, a chloride correction must be completed so that the results are modified to take into account sodium changes. These sodium changes reflect free water levels. Based on this information, your veterinarian will make the diagnosis using the following tools.

• Physical exam
• Blood tests
• Chemistry profile
• Urinalysis

Treatment varies depending on the type of hyperchloremia as well as the cause of the high chloride levels. Some causes of hyperchloremia are easier to treat than others. Depending on other symptoms, an additional diagnosis may be made. Treatment of the underlying cause will likely resolve the high levels of chloride. However, possible hyperchloremia treatments include:

• Therapy to remove the source of the chloride
• Administration of sodium bicarbonate

The length and extent of the treatment will be contingent on the condition of your pet when he arrives at the clinic. If he needs to be stabilised before treatment can begin, the veterinarian will give intravenous therapy, in addition to medications that will make your dog more comfortable as the treatment takes place.

Recovery and management will depend largely on the cause of the elevated chloride levels. If there is no associated cause, recovery should be quick and the dog should be able to return to life as normal. If the cause is more serious, recovery and prognosis will vary.