Introduction
Transient pseudohypoaldosteronism in infants is a renal tubular resistance to aldosterone characterized by hyponatremia, metabolic acidosis, hyperkalemia, and an inappropriately high serum aldosterone concentration. It is a rare renal tubulopathy secondary to urinary tract infection (UTI) and urinary tract malformation (UTM). It is seen in infants, usually within the first six months of their lives.
It is characterized by an imbalance in the body's electrolyte (salt) levels caused by the kidneys' incapacity to react to the hormone aldosterone. Various symptoms and problems may result from this imbalance. Clinical manifestations include dehydration, vomiting, and poor oral intake. Transient pseudohypoaldosteronism is usually a temporary condition that resolves with proper treatment and follow-up.
What Are the Different Types of Pseudohypoaldosteronism in Infants?
Pseudohypoaldosteronism (PHA) is categorized into types 1 and 2 pseudohypoaldosteronism. The type 1 PHA is divided into primary and secondary (transient) PHA. Mutations in the gene encoding the type 1 epithelial sodium channels or mineralocorticoid receptors cause primary PHA. Urinary tract infections (UTIs), mostly brought on by structural abnormalities of the urinary system, are typically the source of secondary (transient) PHA.
What Are the Causes of Transient Pseudohypoaldosteronism in Infants?
There are several potential underlying reasons for transient pseudohypoaldosteronism in babies.
The following are some typical causes of this condition:
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Reduced Aldosterone Action: The adrenal glands secrete the hormone aldosterone, which acts on the kidneys to control potassium and salt levels. brief pseudohypoaldosteronism is characterized by a brief resistance to aldosterone or an inadequate response to it, which causes the kidneys to retain more potassium and reabsorb less salt.
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Urinary System Abnormalities: Birth defects affecting the urinary system can interfere with the regular flow of urine, which can cause an electrolyte build-up and temporarily induce pseudohypoaldosteronism.
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Kidney Abnormalities: This disorder can be caused by structural or functional abnormalities in the kidneys, such as hydronephrosis (excess fluid in the kidney) or nephrocalcinosis (deposition of calcium salts in kidney tubules), which can affect the proper control of electrolytes.
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Genetic Factors: The capacity of the renal system to efficiently control electrolytes may occasionally be impacted by a genetic mutation or predisposition.
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Medication: Some drugs, particularly diuretics, can cause temporary pseudohypoaldosteronism by interfering with electrolyte homeostasis.
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Infections: The kidneys' capacity to maintain appropriate electrolyte levels can be impacted by infections, especially urinary tract infections.
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Dehydration: Conditions that lead to dehydration or an inadequate intake of fluids might worsen an electrolyte imbalance.
What Are the Symptoms of Transient Pseudohypoaldosteronism in Infants?
Whether primary or secondary (transient), infant pseudohypoaldosteronism can present with a variety of symptoms.
Typical signs and symptoms include:
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Dehydration: Infants with pseudohypoaldosteronism may get dehydrated due to the imbalance in electrolytes, especially low sodium levels.
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Lethargy: Babies impacted by the electrolyte imbalance may experience weariness and lethargy.
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Poor Feeding: Babies may show less interest in eating or have trouble feeding themselves appropriately due to discomfort and dehydration.
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Irritability: Electrolyte imbalances can produce pain, making people more irritable and fussy.
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Vomiting: Vomiting is a common side effect of pseudohypoaldosteronism in newborns and can aggravate electrolyte and fluid imbalances.
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Failure to Thrive: In extreme circumstances, the illness may hinder the baby's development and growth, which makes it impossible for them to flourish.
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Hyponatremia and Hyperkalemia: Two particular electrolyte abnormalities linked to pseudohypoaldosteronism are hyponatremia and hyperkalemia. Both excessive potassium (hyperkalemia) and low sodium (hyponatremia) can have a variety of systemic consequences.
How to Diagnose Transient Pseudohypoaldosteronism in Infants?
The diagnosis of transitory pseudohypoaldosteronism in infants is made up of imaging examinations, laboratory testing, and clinical assessment.
The main actions usually performed in the diagnostic procedure are as follows:
Clinical Evaluation:
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Medical History: The healthcare professional will take a history of the infant's illnesses, taking into account any symptoms, eating habits, and potential causes of electrolyte imbalances.
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Physical Examination: Signs such as dehydration, poor eating, lethargy, or irritability may be found with a complete physical examination.
Laboratory Tests:
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Blood Tests: Electrolyte values, particularly those of sodium and potassium, must be measured to diagnose pseudohypoaldosteronism. Typical results include elevated potassium levels (hyperkalemia) and decreased sodium levels (hyponatremia).
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Renal Function Tests: Blood tests, such as those measuring creatinine and blood urea nitrogen (BUN), assess renal function and kidney health.
Imaging Research:
- Ultrasound: To evaluate the anatomy and functionality of the kidneys, imaging tests like renal ultrasonography may be carried out. This can assist in determining whether renal problems or abnormalities of the urinary system aggravate the illness.
What Are the Treatment Options for Transient Pseudohypoaldosteronism in Infants?
Initial Supportive Measures:
Patients suffering from shock and hypovolemia (decrease in liquid portion in plasma) due to pseudohypoaldosteronism (PHA) should be given fluid resuscitation using an isotonic sodium chloride solution at a rate of 20 milliliters per kilogram for a duration of 30 to 60 minutes. Fluid boluses might be given again until the important organs show indications of better perfusion.
Serum potassium levels in patients with severe hyperkalemia should be lowered with cation exchange resins before receiving intravenous (IV) 10 percent calcium gluconate (0.5 to 1 milliliter/kilogram) to preserve the heart muscle and sodium bicarbonate to transfer potassium intracellularly. Severe hyperkalemia should be treated with IV glucose (0.5 to1 gram/kilogram) and insulin (0.1 units/kilogram) over 30 minutes.
Correction of Acidosis and Hyperkalemia
Agents listed below may be utilized in the treatment of PHA:
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Resins that bind potassium.
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Inhibitors of prostaglandins.
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Alkalizing substances.
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In PHA type II (PHA-II), Hydrochlorothiazide is used.
Patients with PHA-II should not use angiotensin-converting enzyme (ACE) inhibitors since they might worsen hyperkalemia, which can be fatal. Most of the time, no surgical treatment is required. It is appropriate to consult with a nephrologist and an endocrinologist. A trained professional should offer the patient genetic counseling.
Nutrition and Exercise
Supplementing with sodium chloride during infancy can rectify hyponatremia and hyperkalemia in children with renal PHA-I, relieve symptoms, and improve development. A low-potassium (0.6 milliequivalents/kilogram/day) and a high-sodium (10 to 15 milliequivalents/kilogram/day) diet are typically beneficial in avoiding hyperkalemia and volume depletion. When patients grow an appetite for salt and show no symptoms when eating a regular diet beyond infancy, sodium chloride supplementation may be reduced or stopped. When older children and adults reduce their salt intake, their symptoms may return.
Conclusion
Infants with transient pseudohypoaldosteronism have an uncommon and transient disorder that has to be treated right away. The prognosis is usually good with the right diagnosis and treatment, even if the symptoms might be worrisome. It is critical to get medical help as soon as possible if the infant or child may be exhibiting signs of transitory pseudohypoaldosteronism so they may receive a thorough assessment and the right treatment.
