Blue baby syndrome, also known as infant methemoglobinemia, is a condition where a baby’s skin turns blue. This occurs due to a decreased amount of hemoglobin in the baby’s blood.
Hemoglobin is a blood protein that is responsible for carrying oxygen around the body and delivering it to the different cells and tissues.
When the blood is unable to carry oxygen around the body, the baby turns blue (cyanotic).
Blue baby syndrome is rare in industrialized countries, but it does occasionally occur in rural areas. Babies born in developing countries with poor water supply continue to be at risk for the condition.
The most common cause of blue baby syndrome is water contaminated with nitrates.
After a baby drinks formula made with nitrate-rich water, the body converts the nitrates into nitrites. These nitrites bind to the hemoglobin in the body, forming methemoglobin, which is unable to carry oxygen.
Nitrates are most common in drinking water in farming communities that use well water. This contamination is due to the use of fertilizers and manure.
Infants younger than 3 months are at highest risk for blue baby syndrome, but it can also occur in other populations.
People at risk for methemoglobinemia include adults with:
- a genetic predisposition
- ulcers or gastritis
- kidney failure requiring dialysis
Other conditions that can cause a baby to appear blue include:
- Tetralogy of Fallot (TOF): TOF is a serious congenital heart condition causing four structural abnormalities in the heart that lead to a lack of oxygen in the blood. This condition can cause a baby to look blue, though it usually occurs at birth.
- Other congenital heart abnormalities: Any congenital heart abnormality that affects the amount of oxygen in a baby’s blood can cause their skin to turn blue.
- Methemoglobinemia: This is due to exposure to inhaled nitric oxide, or certain anesthetics and antibiotics.
The most common symptom of blue baby syndrome is a blue discoloration of the skin around the mouth, hands, and feet. This is also known as cyanosis and is a sign that the child or person is not getting enough oxygen.
Other potential symptoms of blue baby syndrome include:
- difficulty breathing
- vomiting
- diarrhea
- lethargy
- increased salivation
- loss of consciousness
- seizures
In severe cases, blue baby syndrome can even cause death.
A doctor may suspect that an infant has blue baby syndrome during a regular checkup. Parents or caregivers who notice a bluish discoloration should schedule an appointment with a doctor.
The doctor will begin the diagnosis by taking a thorough medical history by asking about any symptoms, feeding patterns, and the conditions at home. They will then perform a physical exam, looking at the discolored areas discoloration and listening to the heart and lungs.
Additional diagnostic tests may include:
- blood tests
- chest X-rays to look at the lungs and heart
- echocardiogram to look at the heart and how well it functions
- oxygen saturation to determine how much oxygen is in the blood
- cardiac catheterization to directly look at the blood vessels and structures inside the heart
In addition to testing the baby, it is possible to get the tap water tested to measure the nitrate levels.
In general, water with nitrate levels below 10miligrams per liter (mg/L) is considered safe. If a water sample has nitrate levels above 10mg/L, do not give it to an infant.
Treatment will vary depending on what is causing the baby to turn blue. If congenital heart disease is causing the discoloration, surgery may be required to correct the abnormalities.
A surgeon will usually operate before the baby turns 1 year old, ideally at around 6 months of age, or even a little earlier. Successful surgery means that the baby will start to get more oxygen and will no longer look blue.
If high nitrate levels in the water are causing blue baby syndrome, the doctor will likely need to consult with the local poison control center or toxicologist to help figure out the best way to treat the condition.
Avoiding the source of nitrate contamination, such as well water or tap water, is essential for all children with this condition.
Doctors may monitor children with a mild form of blue baby syndrome to make sure that they do not develop any further health problems as a result of the condition.
Children with a more severe form of the condition may need a medication called methylene blue, which a doctor will give as an injection.
Blue baby syndrome is a rare condition that occurs when infants drink formula that has been made with water contaminated by high levels of nitrates.
For this reason, it is essential to avoid giving infants water from a well until they turn at least 1 year of age. Medication and monitoring the baby can usually prevent any complications. Left untreated, however, blue baby syndrome can be life-threatening.
Most children with blue baby syndrome go on to live a normal and healthy life without lasting health complications.