What is (Apparently Sporadic) Spastic Paraplegia?

Many individuals with all the signs and symptoms of HSP do not appear to have similarly affected family members. Without proof of a hereditary link, some neurologists call the condition Spastic Paraplegia or Apparently Sporadic Spastic Paraplegia. Other clinicians may diagnosis the same condition as Primary Lateral Sclerosis (PLS), which mimics HSP in how it affects the lower body. However, current researcher indicates that PLS eventually affects the arms and speech and swallowing muscles as well as the leg muscles. There are many reasons why someone with HSP may not have a family history. Recessive and x-linked forms skip generations, which means the disorder may pass silently for generations and then suddenly appear. In addition, the age of onset, progression rate and severity vary widely so that the disease could have gone undiagnosed in previous generations or an affected individual may have died before symptom onset. Mistaken parentage or new genetic mutations are also possible. Please see Heredity and Genetics for more information on this and genetic testing.