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Lysosomal storage diseases

Niemann-Pick disease type C (NPC)

An inherited lysosomal storage disease in which fats such as cholesterol build up in the cells. It can begin at any age. Over time, it leads to nervous system problems that get worse.

Not part of the panel of Türkiye's National Newborn Screening Programme (heel-prick test). Source

Prepare an emergency card

This page is translated from the Turkish original.

This disease is followed through the “Lysosomal storage diseases” group.

Understanding the disease

This section has not yet been reviewed by a physician. It summarises patient information from sources such as MedlinePlus, Orphanet and the NHS in plain language. The disease can differ from person to person; talk to your doctor about diagnosis and treatment.

What happens in this disease?

Inside the cells, cholesterol and other fats cannot be transported normally. These fats build up in the cells. Over time, the cells lose their function and die. It is a disease that progresses over time.

Which symptoms can occur?

Symptoms often begin in childhood but can begin at any age. Symptoms of the nervous system increase over time.

  • Jaundice, large spleen or liver in the newborn (in some babies)
  • Problems with balance and coordination of movement (ataxia)
  • Difficulty moving the eyes up and down
  • Difficulty speaking and swallowing; this increases over time
  • Decline in learning and thinking skills
  • Seizures (in about one in three people)
  • Sudden loss of muscle tone triggered by strong emotions (cataplexy)
  • Mental health problems in the later-onset types (common)

How is it diagnosed?

For the diagnosis, some special markers can be measured in the blood. A special staining test can be done on cells. The diagnosis is confirmed with a genetic test.

Treatment and care

Care is mostly aimed at the symptoms and is supportive. A group of medicines that reduces the production of the fats that build up is approved. Other treatments are being researched. The doctor who follows the disease decides which treatment is suitable.

For the family: inheritance and genetic counselling

The disease is passed on through recessive inheritance. The mother and father are often healthy carriers. For a couple who are both carriers, the chance of having an affected child is 1 in 4 in each pregnancy. Genetic counselling is recommended for brothers and sisters and for future pregnancies.

Source: MedlinePlus Genetics — Niemann-Pick disease · Orphanet — Niemann-Pick disease type C

Key facts

How common is it?
Prevalence: 1-9 per 100 000 (Europe)
How is it inherited?
Autosomal recessive
When does it usually start?
Any age
Gene(s) involved
NPC1, NPC2

These facts are taken from Orphanet and MedlinePlus records (last checked: October 7, 2026). Frequency values are approximate ranges.

You are not alone: patient associations in Türkiye

Non-profit patient and family organizations in Türkiye working on this disease or disease group. Links are for information; Doktorclub is not affiliated with these organizations and does not endorse them.

For all rare diseases: Nadir Hastalıklar Federasyonu

Links checked on October 8, 2026.

Support and help

Doktorclub does not diagnose, recommend treatments or refer you to hospitals or doctors. These pages are meant to help you talk with your doctor.

News about NPC

Clinical trials (ClinicalTrials.gov)

A clinical trial is a regulated study that tests whether a new treatment is safe and whether it works, in patients who volunteer. Most trials look for a certain age, genetic change and health condition. Taking part is voluntary.

This list is not a treatment recommendation. Treatments tested in phase 1–3 trials are investigational (experimental): their efficacy and safety have not yet been proven and they are not approved treatments. Taking part depends on each trial’s criteria and a physician’s assessment; the first step is to talk to the doctor who manages your care.

Questions you can ask your doctor

  • Could this trial be suitable for us?
  • If we take part, how would current treatment and check-ups be affected?
  • Where does the trial take place, and how are travel and accommodation handled?
  • What happens if we want to leave the trial?

ClinicalTrials.gov lists 4 active interventional studies for this disease. 4 are recruiting now; 2 have sites in Türkiye. Last checked: October 7, 2026.

Selected records (studies with a site in Türkiye first):

See all studies on ClinicalTrials.gov · Joining clinical trials

Lysosomal storage diseases: other news

Medical codes (for talking with your doctor and finding sources)

These codes identify the disease in international classifications and databases. They can help when you talk with your doctor or look for reliable sources.

Orphanet code: ORPHA:646

No separate ICD-11 code; WHO classifies this disease under: 5C56.0Y (Other specified sphingolipidosis)

Codes checked against WHO ICD-11 and Orphanet on October 6, 2026.

This page provides general information and does not replace diagnosis or treatment. Talk to your doctor about symptoms, diagnosis and treatment.

The information on these pages is for general information only and does not replace medical advice. Talk to your doctor about diagnosis and treatment decisions. In an emergency in Türkiye, call 112.

Every update is based on an open source and labeled with its level of evidence. No advertising and no drug brand names. Our scientific principles

This page was translated from Turkish by the Doktorclub editorial team.