Rare Diseases: Paraneoplastic Neurologic Syndromes

Paraneoplastic Neurologic Syndromes (PNS) are a group of rare disorders that tend to develop in some people with certain forms of cancer. It is commonly associated with lymphoma or lung, breast and ovarian cancer. People afflicted with this disorder experience problems with muscle movement and coordination. They also present issues with sensory perception, they might have problems related to memory loss, decreased thinking skills, slurred speech and disrupted sleeping habits. Severe cases can even result on irreversible neurological damage. 

So, how exactly does this happen? PNS tend to occur when agents applied to fight cancer attack nerve or sometimes even muscle cells. These syndromes are a collection of symptoms that result from substances produced by the tumor when being attacked by cancer-fighting agents. When a tumor is present, the normal response by the human body is to produce antibodies to fight it destroying tumor cells. On some very rare occasions the same antibodies cross-react with normal tissues and attack them, this is what it is called a paraneoplastic disorder. What causes this can be caused by the presence of some substances produced by the same tumor, they may produce hormones, enzymes or cytokines, those substances can cause the reaction from the antibodies, making them attack normal tissues. When such action occurs in the brain the effects can lead to more serious and sensible effects on the body.
The range of the reactions to the presence of these substances can be from anything as simple as a simple fever, however they can result in more sensible effects such as memory loss. The ways these syndromes manifest themselves have been completely intriguing to say the least. The complex nature of these disorders and the rarity on which they affect made it very difficult for physicians to detect them. Althoguh there are records that these disorders were first reported on the late 19th century, it wasn’t until 1965 that the first report of the discovery of a paraneoplastic anti-neural antibody. PNS can be diagnosed by laboratory tests such as a blood test or a lumbar puncture, also they can be detected by imaging tests such as Computerized Tomography (CT), Magnetic Resonance Imaging (MRI) and Positron Emission Tomography (PET). 
PNS cases are rare, but in many cases they can be treated with the aid of special medications and physical and speech therapy for rehabilitation. Research for these disorders are constantly providing developments on the treatment of the disorder, there are also programs like www.globalgenes.org that are leading in patient advocacy, providing hope for patients worldwide.

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