Choreo-athetotic CP is characterized by involuntary movements, whereas dystonic CP is characterized by slow, strong contractions, which may occur locally or encompass the whole body. Mixed
Mixed cerebral palsy has symptoms of dyskinetic, ataxic and spastic CP appearing simultaneously, each to varying degrees, and both with and without symptoms of each. Mixed CP is the most difficult to treat as it is extremely heterogeneous and sometimes unpredictable in its symptoms and development over the lifespan. Gait Classification
In patients with spastic hemiplegia or diplegia, various gait patterns can be observed, the exact form of which can only be described with the help of complex gait analysis systems. In order to facilitate interdisciplinary communication in the interdisciplinary team between those affected, doctors, physiotherapists and orthotists, a simple description of the gait pattern is useful. J. Rodda and H. K. Graham already described in 2001 how gait patterns of CP patients can be more easily recognized and defined gait types which they compared in a classification. They also described that gait patterns can vary with age. Building on this, the Amsterdam Gait Classification was developed at the free university in Amsterdam, the VU medisch centrum. A special feature of this classification is that it makes different gait patterns very easy to recognize and can be used in CP patients in whom only one leg and both legs are affected. According to the Amsterdam Gait Classification, five gait types are described.
Cholesterol is a major component of cell plasma membranes, which define the cell as a whole and its organelles. It is also the basic building block of steroid hormones, including neurosteroids. In Niemann–Pick type C, large amounts of free or unesterified cholesterol accumulate in lysosomes, and leads to relative deficiency of this molecule in multiple membranes and for steroid synthesis. The accumulation of glycosphingolipids in the nervous system has been linked to structural changes, namely ectopic dendritogenesis and meganeurite formation, and has been targeted therapeutically.Several theories have attempted to link the accumulation of cholesterol and glycolipids in the lysosomes with the malfunction of the NPC-1 protein. Neufeld et al. hypothesized that the accumulation of mannose 6-phosphate receptors (MPRs) in the late endosome signals failure of retrograde trafficking of cholesterol via the trans Golgi network. Another theory suggests that the blockage of retrograde cholesterol breakdown in the late endosome is due to decreased membrane elasticity and thus the return vesicles of cholesterol to the trans Golgi Network cannot bud and form. Iouannou, et al. have described similarities between the NPC1 protein and members of the resistance-nodulation-division (RND) family of prokaryotic permeases, suggesting a pumping function for NPC1. Recent 2008 evidence indicates that NPC-1 may play an important role in calcium regulation. Diagnosis
Niemann–Pick type C is diagnosed by assaying cultured fibroblasts for cholesterol esterification and staining for unesterified cholesterol with filipin. The fibroblasts are grown from a small skin biopsy taken from a patient with suspected NPC.