Spina Bifida: Causes, Types, Symptoms, Diagnosis & Treatment

Spina Bifida is a condition that some babies are born with. It happens when the protective layer around the spinal cord (called the neural tube) doesn't close all the way during pregnancy. This gap means the spinal cord can be exposed or damaged. 

There are different kinds of Spina Bifida: some are mild and hidden (Occulta), while the most severe (Myelomeningocele) creates a visible sac on the baby's back containing nerves, which can cause serious walking and health problems. Learn about Spina Bifida for NEET PG here.

Spina Bifida

Spina Bifida is a condition present at birth where the spine and spinal cord do not form correctly. This happens early in pregnancy, affecting the neural tube. The neural tube develops into the baby's brain, spinal cord, and surrounding tissues. When it fails to close completely, it leads to varying health issues. Knowing about Spina Bifida helps in effective management and care.

Types Of Spina Bifida

Spina Bifida has several forms, each with different levels of severity:

• Spina Bifida Occulta
  Occulta means hidden. This is the most common and mildest type. One or more vertebrae in the spine have a small gap. Often, people with Spina Bifida Occulta do not know they have it unless imaging tests show it for another reason.

• Myelomeningocele
  This is the most severe type. The spinal canal remains open in many vertebrae in the lower or middle back. The baby's membranes and spinal nerves push through this opening, forming a sac on the back. This can expose tissues and nerves, leading to infection risk, paralysis, and bladder or bowel problems.

• Meningocele
  This is a rare type. A sac of spinal fluid bulges through a spinal opening. This form does not include the spinal cord or nerves. Meningocele in babies might cause minor functional issues, often affecting the bladder and bowels.

Cause Of Spina Bifida

The exact cause of Spina Bifida is unknown. It is believed to result from a mix of genetic and environmental factors.

Symptoms Of Spina Bifida

Spina Bifida signs and symptoms vary greatly by type and severity.

• Spina Bifida Occulta
  Often, there are no symptoms because spinal nerves are not affected. Sometimes, a tuft of hair, a small dimple, or a birthmark appears on the skin above the spinal issue.

• Meningocele
  This type can lead to problems with bowel and bladder control.

• Myelomeningocele
  This severe form shows an open spinal canal. The spinal cord or nerves, along with membranes, protrude, forming a sac at birth. Tissues and nerves are often visible.

Risk Factors Of Spina Bifida

Some factors increase the chance of having a baby with Spina Bifida.

• Deficiency in Folate
  Folate, a B-9 vitamin, is vital for healthy baby development. A lack of folate increases the risk of neural tube defects like Spina Bifida. Folic acid is the synthetic form used in supplements.

• Neural Tube Defects Run in the Family
  The risk slightly increases if a couple has had a child with a neural tube defect. The risk is higher if two siblings have the condition.

• Certain Drugs
  Some anti-seizure drugs, like valproic acid, can cause neural tube defects. They might stop the body from using folic acid properly.

• Diabetes
  Pregnant women with uncontrolled blood sugar have a higher risk of having a baby with Spina Bifida.

• Obesity
  Being obese before pregnancy raises the chance of a neural tube birth defect.

• Elevated Body Temperature
  High body temperature, from fever or using saunas/hot tubs in early pregnancy, might increase Spina Bifida risk.

Diagnosis Of Spina Bifida

Doctors offer prenatal screening to check for Spina Bifida and other birth issues.

• Blood Test: The Maternal Serum Alpha-Fetoprotein (MSAFP) test checks the mother's blood for Alpha-fetoprotein (AFP). High AFP levels can signal a neural tube defect.

• Confirm Elevated AFP Levels: If AFP levels are high, a follow-up blood test and an ultrasound are needed to confirm. Other factors can also cause high AFP.

• Ultrasound: Foetal ultrasonography is the most reliable way to identify Spina Bifida before birth. A second-trimester ultrasound (18 to 22 weeks) can effectively find the condition. It also helps determine the severity.

• Amniocentesis: If ultrasound confirms Spina Bifida, amniocentesis may be suggested. This test takes a fluid sample from the amniotic sac. It can rule out genetic illnesses.

Treatment Of Spina Bifida

More severe forms of Spina Bifida involve nerve damage which cannot be healed.

• Management: Treatment involves surgery, physiotherapy, and medication.

• Mobility Support: Some individuals need catheters for urine movement. Many will need wheelchairs, crutches, or braces throughout their lives.

• Learning Difficulties: Patients with Spina Bifida, especially those with hydrocephalus, sometimes have learning difficulties. These include problems with attention, communication, organisation, and sequencing.

Complications Of Spina Bifida

The severity of complications depends on the neural tube defect's size, location, and nerve involvement. Many complications are treatable.

• Mobility Issues: Nerves controlling leg muscles do not work properly below the defect site. This causes leg muscle weakness or paralysis.

• Orthopaedic Problems: Weak leg and back muscles in Myelomeningocele patients can lead to issues like curved spine (scoliosis), hip dislocation, and joint disorders.

• Bowel and Bladder Issues: Nerves supplying the bladder and bowels often malfunction in children with Myelomeningocele.

• Fluid Buildup in the Brain (Hydrocephalus): Babies with Myelomeningocele often develop hydrocephalus.

• Shunt Error: Shunts used for hydrocephalus can stop working or get infected. Warning signs include headaches, vomiting, and irritability.

• Chiari Malformation Type II: This brain problem is common in Myelomeningocele. The brainstem is lower than normal, causing breathing and swallowing problems.

• Meningitis: This is an infection of the membranes covering the brain. It can be fatal.

• Tethered Spinal Cord: Spinal nerves attach to the surgical scar. This limits spinal cord expansion as a child grows. It can cause muscle function loss in legs, colon, or bladder.

• Breathlessness While Sleeping: Spina Bifida, especially Myelomeningocele, can cause sleep apnea.

• Skin Conditions: Children with Spina Bifida may get injuries, blisters, or sores on their feet, legs, or buttocks due to lack of feeling.

• Latex Sensitivity: A latex allergy is more common in children with Spina Bifida.

• Other Issues: As children grow, other problems can arise, like urinary tract infections, GI issues, and depression.

Prevention

Taking folic acid supplements significantly reduces the risk of Spina Bifida and other neural tube defects.

• Folic Acid Supplementation
  Experts advise all women of reproductive age to take 400 micrograms (mcg) of folic acid daily. This should start at least one month before conception and continue through the first trimester of pregnancy.

• Folic Acid Enriched Foods
  Many foods are fortified with 400 mcg of folic acid. These include enriched bread, rice, pasta, and some breakfast cereals. Folate is the natural form of folic acid found in foods.