Diagnostically, it is important to distinguish it from polyneuropathy because when a single nerve is affected, it is more likely to be due to localized trauma or infection.The most common cause of mononeuropathy is physical compression of the nerve, known as compression neuropathy. Carpal tunnel syndrome and axillary nerve palsy are examples. Direct injury to a nerve, interruption of its blood supply resulting in (ischemia), or inflammation also may cause mononeuropathy. Polyneuropathy
"Polyneuropathy" is a pattern of nerve damage that is quite different from mononeuropathy, often more serious and affecting more areas of the body. The term "peripheral neuropathy" sometimes is used loosely to refer to polyneuropathy. In cases of polyneuropathy, many nerve cells in various parts of the body are affected, without regard to the nerve through which they pass; not all nerve cells are affected in any particular case. In distal axonopathy, one common pattern is that the cell bodies of neurons remain intact, but the axons are affected in proportion to their length; the longest axons are the most affected. Diabetic neuropathy is the most common cause of this pattern. In demyelinating polyneuropathies, the myelin sheath around axons is damaged, which affects the ability of the axons to conduct electrical impulses. The third and least common pattern affects the cell bodies of neurons directly.
MMF was judged a consequence of a switch to intramuscular injection and the deltoid muscle being the preferred site of both vaccine injection and biopsy in France (while other sites were preferred for biopsy in other countries) and the commencement of HBV vaccination in French adults. Similar lesions could be detected in babies and children upon biopsy of the quadriceps as this is the site of vaccine administration in this group. MMF could also be experimentally reproduced in animals, with regression over time. It has been proposed that in a small portion of the population, vaccination results in persistence of aluminium-compound particles in macrophages in association with myalgia, fatigue, and cognitive dysfunction. A MMF disorder has been compared to autoimmune/inflammatory syndrome induced by adjuvants. A case-controlled study in France found those with MMF were more likely to have received aluminium-containing vaccines. MMF was also associated with fatigue “and related functional limitations", with fatigue more common in the beginning of the malady that led to the biopsy. However, neither myalgia, arthralgia, nor any other symptoms or risk factors were identified as specific to those with MMF.Many of those with MMF had previously been treated for malaria with chloroquine or hydroxychloroquine.As of 2009, with few exceptions, MMF had only been reported in France. == References ==