This blood test measures essential electrolytes such as sodium, potassium or calcium. Indications, normal values, interpretation of results… here is what you need to know to understand this key examination.
This examination makes it possible to check the water and electrolyte balance, a mechanism permanently regulated by the kidneys, but also by the skin, breathing and the digestive system. It is often requested in cases of unusual fatigue, dehydration, kidney or digestive problems, or to monitor certain treatments.
Definition: what is a blood ionogram?
A blood cell count is a common blood test prescribed to assess the balance of electrolytes in the body. It measures the concentration of several essential ions present in plasma, including sodium (Na), potassium (K), calcium (Ca), chlorine (Cl) and bicarbonates (HCO₃⁻). These elements play a key role in the proper functioning of cells, muscles and the nervous system. “The blood ionogram is an essential test to know the general functioning of our body. It can reveal many pathologies which could go unnoticed, in particular any kidney dysfunction. It must be part of any general screening assessment”explains Dr Marc Druet, general practitioner.
What are the normal values of a blood ionogram?
The results of a blood ionogram, generally performed on an empty stomach, must fall within reference ranges which may vary slightly depending on the laboratory. For information only:
- Sodium: between 135 and 145 mEq/L
- Potassium: between 3.5 and 5 mmol/L
- Calcium: between 90 and 100 mg/L
- Chlorine: between 95 and 105 mmol/L
- Magnesium: between 0.75 and 1 mEq/L
- Bicarbonates: between 22 and 30 mmol/L
These values make it possible to identify an imbalance, but are not sufficient to make a diagnosis. Their interpretation must always be made by a doctor, taking into account the symptoms and the clinical context, in order to decide whether additional examinations or treatment are necessary.
What does a high blood cell count mean?
► Hypernatremia: the increase in sodium levels (hypernatremia) can be the consequence of a reduction in the quantity of water (dehydration): digestive losses, reduced water intake, significant water loss, sweating or a sodium overload.
► Hyperkalemia : An increase in potassium levels (hyperkalemia) may be encountered in people taking potassium supplements, or taking medications such as antihypertensives, anti-inflammatories, in cases of kidney failure, etc.
► Hypercalcemia: Too high a level of calcium in the blood can be due to hyperparathyroidism, menopause, vitamin D intoxication, prolonged immobilization as well as certain cancers.
► Hyperchloremia: The chlorine level may increase (hyperchloremia) during excessive dehydration through sweating, digestive losses, sodium overload, hypoparathyroidism. or medullary thyroid cancer.
► The bicarbonate level may increase in people with the following pathologies, such as chronic respiratory failure or metabolic alkalosis due to repeated vomiting or diarrhea.
What does a low blood cell count mean?
► Hyponatremia. The sodium level may experience a decrease, which is called Hyponatremia, “A distinction must be made between depletion hyponatremia: during the consequences of a deficit in sodium intake or excessive loss (renal loss through diuretics or digestive loss through diarrhea); And dilution hyponatremia: consequence of an increase in the quantity of water (pathological hyperhydration such as potomania) or during cardiac, renal, or hepatic failure, creating edema”, specifies the general practitioner.
► Hypokalemia. A decrease in potassium levels (hypokalemia) may be seen in people suffering from vomiting or diarrhea or taking diuretic medications.
► Hypocalcemia. Low calcium levels (hypocalcemia) in the blood may be due to impaired absorption from the intestine, vitamin D deficiency, chronic kidney failure, hypoparathyroidism, or medullary thyroid cancer.
► Hypochloremia. The chlorine level may experience a decrease (hypochloremia) in the following cases due to the consequences of a deficit in sodium intake: digestive (diarrhea) and renal losses, an increase in the quantity of water or excessive sweating.
► The level of bicarbonates may decrease when metabolic acidoses, ketoacidoses occurring in diabetics, states of shock (lactic acidosis),renal failure, severe hepatic failure or chronic hyperventilation.
What are the treatments for abnormal blood ionograms?
“The treatments are numerous and varied, they will depend on the cause”, explains Dr. Marc Druet. For example, in cases of hypercalcemia, the patient will be administered medications that increase urinary calcium excretion.
Thanks to Dr Marc Druet, general practitioner.








