Neonatal Bartter Syndrome - Causes, Symptoms, Complications, and Management

What Is Neonatal Bartter Syndrome?

Neonatal Bartter syndrome is caused by a variation in the level of sodium, potassium, and chloride. This imbalance causes different disorders related to the kidneys. During this disorder, every urine excretion loses calcium and sodium from the body in an abnormal amount. Moreover, this can create an excessive loss of potassium and raise the level of acid in the body, which can cause a myriad of health complications. The syndrome is usually characterized by health-related complications, such as metabolic alkalosis, hypochloremia, hypokalemia, or hyperreninemia. If the syndrome is causing any of the above complications during any stage of pregnancy, there are chances of the premature birth of an infant too.

What Are the Different Forms of Neonatal Bartter Syndrome?

Depending on the onset and severity, there are following two different forms of Bartter syndrome, such as:

• Antenatal Bartter Syndrome: This is an inherited form of Bartter syndrome in which health-related complications are detected around 24 to 30 weeks of pregnancy. It is a rare as well as a severe form of Bartter syndrome. There are complications such as polyhydramnios, and polyuria seen associated with it.

• The Classic Form of Bartter Syndrome: This form begins around an early age in children. This is comparatively less severe than the other type of the syndrome.

What Are the Causes of Neonatal Bartter Syndrome?

Bartter syndrome is the result of a mutation in the genes, which is autosomally recessive in nature. This means that to have this abnormality, the infant must have one or two mutated genes received from each parent.

The type of syndrome depends on which type of gene is mutated. It is known that around five mutated genes are responsible for this abnormality. These genes play an essential role in maintaining normal kidney functions. For instance, genes produce protein, which plays a part in the reabsorption of sodium from the kidneys. If any of the genes are mutated, it disturbs the sodium reabsorption, which causes excessive loss of sodium in the urine. This can further lead to ion disturbance in the body as well as the levels of calcium and potassium.

What Are the Symptoms Associated With Neonatal Bartter Syndrome?

The followings are the signs and symptoms seen associated with Bartter syndrome:

• Constipation.

• Frequent urination.

• Lethargy.

• Fever.

• Diarrhea.

• Vomiting.

• Significant facial features, such as a triangle-shaped face and wide forehead.

• Large ears with pointed ends.

• Deafness.

• Crankiness.

• Constant crying.

• Severe thirst.

• Slower and delayed growth.

• Developmental delays.

How to Diagnose Neonatal Bartter Syndrome?

The following are the diagnostic methods used for Bartter syndrome:

• Molecular Genetic Testing: This test is done to recognize which gene is mutated and causes the disorder. It is to be done before birth to recognize the severity and type of the syndrome. Moreover, this diagnostic option can also reveal the other health-related complications associated with the syndrome as well as malformations. Also, with this test, the level of chloride and aldosterone is measured by testing amniotic fluid.

• Blood Test: This method of investigation can evaluate the level of potassium, chloride, and bicarbonate in the bloodstream.

• Urine Test: This diagnostic method can reveal if the urine has an excessive level of sodium in it.

What Are the Complications Associated With Neonatal Bartter Syndrome?

The following are the complications associated with Bartter syndrome:

• Polyhydramnios: It is a rare condition where the amniotic fluid is excessively accumulated during the second half of the pregnancy. Most cases are mild, but the severity of the condition can lead to the premature birth of the baby.

• Premature Birth: Neonatal Bartter syndrome is associated with polyhydramnios, which is the excessive accumulation of amniotic fluid in the womb. This condition is responsible for complications such as premature rupture of the membrane, premature placental abruption, and umbilical cord prolapse, which leads to the premature birth of the baby.

• Hypokalemia: Hypokalemia is the low level of potassium in the blood. In cases of Bartter syndrome, it is caused by excessive urination and loss of potassium and sodium with it. It can be mild to severe in condition, which can cause weakness, fatigue, or arrhythmia.

• Polyuria: Polyuria is the condition where a person has to urinate excessively. This can cause the imbalance of many important nutrients in the body causing a plethora of health-related complications.

• Osteopenia: Osteopenia is a condition where due to excessive loss of minerals, the bones of the body are weak. This can cause constant pain, fragility, and loss of structure of the bones.

How to Manage Neonatal Bartter Syndrome?

Bartter syndrome has no cure, but it is associated with many health-related complications, and it can be managed by preventing these complications. The following are the treatment options for Bartter syndrome:

• The syndrome is associated with a loss of nutrients from the body, such as electrolytes, sodium, and potassium. These can be managed by providing supplements externally to manage the imbalance. Neonatal Bartter syndrome with severe conditions might require intravenous administration of these supplements. To reduce these excessive losses of nutrients, they are given nonsteroidal anti-inflammatories (NSAID) drugs such as Ibuprofen, Celecoxib, and Indomethacin.

• Potassium-sparing diuretics are used to maintain potassium levels in the body. These are known as Spironolactone or Amiloride. These cause an increase in the loss of sodium in the urine but decrease the potassium level.

• Renin-aldosterone-angiotensin systems (RAAS inhibitors) are used to stop the secretion of Aldosterone and fight the effect of renin. Due to this, the acid loss and potassium secretion from urine are reduced or stopped. However, these drugs can abruptly cause a drop in blood pressure, which can cause fatal conditions in the kidneys and heart. Due to this, the patients should be closely monitored, and if the excessive level of sodium drops the medications should be stopped.

Conclusion

Neonatal Bartter syndrome can be mild to severe in form. Moreover, there is no cure for this syndrome. However, there are many medications available to manage the symptoms and complications associated with it. Parents and caregivers should keep a close eye on the overall condition of newborns as it can cause life-threatening conditions too.