In congenital insensitivity or indifference to pain, a syndrome in which the patient throughout life is unreactive to the pain of injury, there is no loss of the ability to distinguish pinprick and other noxious stimuli from nonnoxious ones. Furthermore, the nervous system of such individuals seems to be normal. There is another variety characterized by universal analgesia (Swanson et al). This latter type is inherited as an autosomal recessive trait and at least one form involves the gene for a nerve growth factor receptor located on chromosome 1q immediately adjacent to the site of the mutation for Charcot-Marie-Tooth disease type 1B (see Table 43-6). During childhood, one of the patients of Swanson and colleagues had high fever when the environmental temperature was raised and the other had orthostatic hypotension. One of the patients died in his twelfth year and was found to have an absence of small neurons in the dorsal root ganglia, an absence of Lissauer tracts, and a decrease in size of the descending spinal tracts of the trigeminal nerves. Sweat glands were present in the skin but were not innervated.
Whereas the usual cutaneous lipomas have no neurologic accompaniments, this clinical curiosity, known as
Launois-Bensaude disease, consists of symmetrical lipomas of the neck and shoulders that are associated with polyneuropathy and sometimes, deafness. A mitochondrial disorder of similar genetic origin as the MERRF syndrome (see Chap. 36) has been identified (see Neumann’s review for clinical details).
This interesting process was mentioned in Chap. 38 in relation to dementia in which it is pointed out that there is a multisystem neurologic disease characterized by the widespread deposition in nervous tissue of corpora amylacea, in this disease termed polyglucosan bodies. The main presentation of this disorder is of slowly progressive motor and pronounced sensory loss in the legs due to an axonal polyneuropathy, neurogenic bladder, and a degree of upper motor neuron signs that may also be evident. It is the early appearance of the urinary difficulties or the upper motor neuron features that mark the illness as unusual in relation to other polyneuropathies. Biopsy of the sural nerve demonstrates profuse deposition of the polyglucosan bodies in the endoneurium. When dementia occurs, either with the neuropathy or in isolation, the corpora amylacea are found throughout the cerebrum. The process is detailed by Robitaille and colleagues and an upper motor neuron presentation that simulates amyotrophic lateral sclerosis, by McDonald and coworkers.
The bodies are made up largely of glucose polymers that are well known to occur in the aging brain and, when present in small numbers, have been assigned an innocuous meaning. In the usual type of polyglucosan disease, which is found in individuals of Ashkenazic Jewish origin, there is a deficiency in glycogen branching enzyme (GBE) that is shared with glycogenosis type IV, and infantile recessive process, Anderson disease. As such, it could be considered with the other neuropathies that have an identifiable metabolic cause, discussed as a group further on. However, a proportion of cases do not have the inherited GBE enzyme abnormality.
Riley-Day Familial Dysautonomia (See Also Chap. 25)