Niemann-Pick disease is a progressive genetic metabolic disorder that affects the body’s ability to metabolize fat within cells. It can occur at any age, but it is common in children. Although research is underway for finding suitable treatment, no complete remedy has yet been found.
It has three categories, and treatment focuses on reducing the symptoms in patients.
What is Niemann-Pick disease?
Niemann-Pick disease is a rare metabolic disorder caused by changes in the structures of specific genes. The disease is inherited only when both the parents pass on the defective gene to their child.
It usually affects children. In individuals with Niemann-Pick disease, fats and lipids accumulate in the liver, spleen, lungs, bone marrow and brain. As a result, the individual may die due to improper functioning of various body functions.
There are three classifications of Niemann-Pick disease:
- Type A: It mainly occurs in infants. Symptoms start showing within the first few months of life. Most children die during infancy.
- Type B: It occurs in mid-childhood, and the affected may or may not survive in adulthood.
- Type C: It is a less common version that develops in early adulthood.
What are the major causes of Niemann-Pick disease?
Types A and B
- Types A and B occur due to the mutations in the SMPD1 gene that helps WBCs to produce acid sphingomyelinase (ASM).
- ASM is an enzyme that metabolizes sphingomyelin, a fatty substance in the body
- SMPD1 mutations (changes in the structure of genes) lead to ASM deficiency, and fat starts building up in the cells. As a result, cells die, and organs stop functioning.
- Type A occurs mainly in babies, who show serious, progressive brain disorder. As there is no cure, most of the children do not live beyond their first few years.
Usually, Type B occurs later in childhood and is not linked to the primary brain disease. A majority of those affected with type B survive into adulthood.
- Type C develops due to the mutations in NPC1 and NPC2 genes that affect a protein used to transport cholesterol and other lipids.
- Mutations lead to a shortage of protein, and cholesterol starts building up in the spleen and the liver.
- Excessive amounts of other fats also start accumulating in the brain.
- Ultimately, it results in cell death and organ failure.
What are the symptoms of Niemann-Pick disease ?
Symptoms of Type A include:
The symptoms of type A form of Niemann-Pick disease are present within the first few months of birth and include:
- Swollen abdomen
- Swollen lymph nodes
- A red spot in the eye
- Feeding difficulties and reduced appetite
- Loss of reflexes, motor skills
- Repeated respiratory problems
Symptoms of Type B include:
The signs and symptoms of the type B form of Niemann-Pick disease usually start to appear in late childhood or at the adolescence age. This form of Niemann-Pick disease does not include motor difficulty which is found commonly in type A disease. The symptoms of type B could include:
- Swollen abdomen
- Respiratory infections
- Mental retardation
- Delayed growth
- Eye abnormalities
- Poor coordination
- Low level of blood platelets
- High level of lipids in the blood
- Enlarged liver and spleen
Type B form of Niemann-Pick disease differs significantly from type A form of Niemann-Pick disease which is a more serious, early-onset form of Niemann-Pick disease, in which symptoms appear in early infancy, development do not progress beyond 12 months level, and survival beyond age three is very rare.
Symptoms of Type C include:
- Enlarged liver and spleen
- Dystonia (excessive muscle contractions resulting in abnormal postures of limbs, face)
- Clumsiness and difficulty walking
- Slurring of speech
- Difficulty swallowing
- Seizures and tremors
- Impaired eye movements
- Recurrent respiratory infections
When should you visit a doctor?
Visit a doctor immediately if you observe any symptoms of Niemann-Pick disease developing in your child.
What are the complications associated with Niemann-Pick disease ?
- Visual impairment
- Brain damage
- Hearing loss
How is Niemann-Pick treated?
Unfortunately, there is no existing cure for Type A Niemann-Pick disease.
Research is underway on using bone marrow transplants, gene therapy and enzyme replacement therapy for Type B disease.
Along with physical therapy that helps with mobility, a drug Miglustat is used to treat Type C disease. An international research study of 92 persons suffering from type C Niemann-Pick disease showed improved neurological symptoms after regularly taking miglustat for an average of two years.
Physiotherapy is a vital part of the treatment, which helps in maintaining mobility as long as possible. Individuals with Niemann-Pick disease have to see their doctors regularly, as the disease progresses and the symptoms can get worse.
Niemann-Pick disease is an inherited disease that disrupts the metabolization of fats and lipids in the body. Types A and B are common in children, while Type C commonly develops in adults. Unfortunately, it is an incurable disease, and over time, causes death . Though doctors are using some treatments to improve the symptoms, the disease does not have cure
Frequently Asked Questions (FAQs)
How is Niemann-Pick disease diagnosed?
For Types A and B: Specialists use blood or skin samples to diagnose the quantity of sphingomyelinase in the white blood cells.
For Type C: Experts take a skin sample to assess the movement of cells and how they store cholesterol.
Some other methods of diagnosis include –
How common is Niemann-Pick disease?
It is a rare disorder that affects approximately 1 in 250,000 individuals.
Which specialist should I consult for this condition?
You should consult a pediatrician if you observe your child developing any warning signs of Niemann-Pick disease .