Think NPC. Talk NPC

Think NPC. Talk NPC is a subsidiary campaign to Think Again. Think NPC, which focuses on how a patient with undiagnosed Niemann-Pick type C disease (NPC) or their carer/family members might describe their symptoms to a healthcare professional, to increase clinical recognition.

As with other rare diseases, the signs and symptoms of NPC are highly variable and not specific to the disease, which means that NPC often goes undetected or is misdiagnosed. By assisting physicians to recognise the symptoms of NPC as they are described in everyday language and link them to the disease, earlier diagnosis and earlier access to care becomes a more achievable goal.

If a friend, family member, or patient presents with symptoms, which one may consider to be related to Niemann-Pick disease type C (NPC), then you should immediately refer this person to a specialist centre for diagnostic testing, the quicker the process is initiated the better. Confirmation of diagnosis will not only help to facilitate access to treatment but will also enable patients and their families to seek help and support from charities and other associated organisations.



Early diagnosis means patients can access support, which can improve their quality of life and the lives of those around them. Early diagnosis is also important as NPC is a treatable disease. Treatment can help to manage the symptoms and can slow down the progression of the disease.

Earlier recognition of key symptoms of NPC is critical in order to achieve an earlier diagnosis for patients. The symptoms of NPC can be categorised as systemic (visceral), neurological or psychiatric. The most common symptoms are shown via the link below.

One of the strongest indicators of NPC is when a patient presents with symptoms in more than one of these categories. Therefore, linking these symptoms together can facilitate a fast and differential diagnosis of NPC.

KEY SYMPTOMS OF NP-C – Download Here

Symptoms present at different ages and in different combinations. The age of onset of visceral symptoms is independent of the onset of neurological disease, which occurs along a continuous spectrum with considerable overlap between the age categories as shown in the diagram (Vanier 2010).


Vertical supranuclear gaze palsy (VSGP) is a very strong indicator of NPC. VSGP often goes undetected, despite it being simple to detect by testing for voluntary saccades. The initial sign is usually impaired voluntary saccadic eye movements (SEM) in the late-infantile period. Vertical SEM impairment is affected first, followed by horizontal SEM impairment.

A rigorous neurological examination of VSGP should include testing of smooth pursuits, saccades, and vergence (movement of the two eyes in opposite directions). In all patients, saccadic, pursuit, and vergence movements should be examined in both vertical and horizontal planes.


NPC can be difficult to recognise because the symptoms can occur at different times and with varying severity in each person. For some patients, symptoms are quickly linked to NPC if their doctor knows about NPC. However, for others, it may take many different doctors a number of years to finally link them together and suspect NPC as there is a lack of clinical awareness about the disease. Once NPC is suspected patients are referred on to a specialist centre for diagnostic testing.

If you suspect a patient has NPC then you can find details of specialist centres in your country.

  • Orpha is a database of information on rare diseases and orphan drugs that aims to help improve the diagnosis, care and treatment of patients with rare disease.
  • INPDA is the International Niemann-Pick Disease Alliance (INPDA) website that provides information about the non-profit organisations that are in place across the globe to support patients and families diagnosed with NPC. You can find more information on the member organisations that make up the INPDA here.
  • INPDR is the International Niemann-Pick Disease Registry (INPDR) website, which provides information about all types of Niemann-Pick diseases and the importance of the registry in collecting data.


"...earlier diagnosis means patients can access vital treatment and support, quicker..."

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