Crit Rev Microbiol. 2003;29(3):215-21. Related Articles, Links Cell wall-deficient (CWD) bacterial pathogens: could amylotrophic lateral sclerosis (ALS) be due to one? Koch AL. Biology Department, Indiana University, Bloomington, IN 47405-6801, USA. koch@Indiana.edu Recently, a number of diseases that had been thought previously to be caused by something other than an infectious agent are now known to be caused by bacteria. It now appears that it is not uncommon that bacteria, viruses, or fungi can cause diseases even when these organisms have not been detected or cultured. The most recent, well-publicized case is that of stomach ulcers; these are largely due to Helicobacter pylori infections. Here, the possibility is explored that amylotrophic lateral sclerosis (ALS) is caused by a cell wall-deficient microorganism. Wien Med Wochenschr. 1995;145(7-8):186-8. Related Articles, Links [ALS-like sequelae in chronic neuroborreliosis] [Article in German] Hansel Y, Ackerl M, Stanek G. Neurologischen Abteilung des Kaiser-Franz-Josef-Spitals, Wien. CSF investigation in a 61-year old female patient with clinical picture of motoneuron disease gave evidence for chronic infection with Borrelia burgdorferi. Improvement of clinical and CSF findings could be observed after antibiotic therapy. The diagnosis of amyotrophic lateral sclerosis which was initially suspected had to be revised and the disorder was interpreted as chronic neuroborreliosis. Rev Neurol (Paris). 1990;146(1):41-4. Related Articles, Links [Amyotrophic lateral sclerosis syndrome of syphilitic origin. 5 cases] [Article in French] el Alaoui-Faris M, Medejel A, al Zemmouri K, Yahyaoui M, Chkili T. Service de Neurologie, Hopital des specialites Rabat, Maroc. We studied 5 cases of syphilitic lateral amyotrophic sclerosis. The diagnosis was based on the presence of a lymphocytic reaction in the CSF and positive VDRL and TPHA reactions in both blood and CSF. Clinically, the disease affected the arms in 3 cases and produced paraplegia in 2 cases. The gradual extension of amyotrophy over several months, the diffusion of electromyographic abnormalities and the finding of spinal cord atrophy at myelography and CT suggested a subacute ischemic mechanism with meningo-myelic arteritis involving the anterior horns. After treatment with penicillin G in high doses, the outcome was constantly favourable, with improvement of motor deficit in 4 cases and stabilisation in 1 case in a 5 to 13 years' follow-up. Clin Exp Pathol. 1999;47(5):207-13. Related Articles, Links [The hypothesis of infectious etiology for idiopathic nervous system diseases: from the postulates of Koch to the criteria of Hill] [Article in French] Belec L. Laboratoire de Virologie, Hopital Broussais, Paris, France. The evaluation of the hypothesis of an infectious etiology to some neurological diseases comprises four different situations. First, numerous neurological diseases have an obvious infectious etiology (encephilitis, meningoencephilitis). Second, some neurological disorders were primarily suspected to be have an infectious etiology, but the causative microorganism was discovered either longtime after the princeps description of the disease (neurologic Whipple disease, due to Tropheryma whippelii), or at the same time (tropical spastic para- paresis secondary to HTLV-I infection). Third, for other neurological diseases, an infectious etiology that was not suspected at time of their anatomoclinic descriptions, was further demonstrated in the context of a generally complex physiopathology (Guillain-Barre syndrome and infection by Campylobacter jejuni). Finally, some idiopathic neurological diseases could be related to well known or yet unknown microorganisms, in association with some environmental factors, and with a particular genetic or acquired susceptibility of the host. The evaluation of an infectious etiology to these idiopathic neurological disorders must be envisioned according to 3 possibilities: 1) generally, the neurological disease is well defined, but its etiology remains unknown and an infectious hypothesis could be relevant (multiple sclerosis, post-polio syndrome, amyotrophic lateral sclerosis); 2) sometimes, a microorganism that is not associated with a known disease, and then qualified as "orphelin", could be associated with neurological disorders (spumaretrovirus); 3) finally, a new neurological disease could be associated with a known or yet unknown microorganism, directly or indirectly. In conclusion, some idiopathic neurological diseases could have an infectious etiology, with physiopathologic, diagnostic, prophylactic (vaccination) and therapeutic (use of anti-infectious drugs) consequences.