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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ischemia plays an important role in the development of neuropathies associated with various disorders, such as peripheral vascular occlusive diseases, necrotizing vasculitides, diabetes mellitus and nerve compression or trauma. Although a multiple mononeuropathy or an asymmetrical polyneuropathy is the usual clinical presentation of ischemic neuropathy, some patients present with a neuropathy that is mainly distal and symmetrical. Pathologically, nerve ischemia results in focal or multifocal central fascicular or sector fiber degeneration. These ischemic lesions tend to begin at mid-upper arm or midthigh level, which is the watershed zone of poor perfusion, and become more diffuse distally. Nerve ischemia at the level of distal small fascicles often induces sub-perineurial crescent lesion rather than central fascicular fiber degeneration. Physiologically, reduced nerve blood flow with endoneurial hypoxia has been demonstrated in experimental diabetic and galactose neuropathies. Endoneurial ischemia/hypoxia in galactose neuropathy appears to be due to increased intercapillary distances and constriction of trans-perineurial vessels resulting from endoneurial edema. Although acute ischemic neuropathy has been well investigated, little is known about functional or structural responses of peripheral nerve to chronic ischemia.
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PMID:[Ischemic neuropathy]. 209 82

29 cases of femoral mononeuropathy are reported. While the clinical features of the femoral neuropathy are easily identified, the etiology is often hard to establish. The cases reported tend to fall into three general categories: 1) cases without major diagnostic difficulties (e.g. diabetic neuropathy); 2) those in which the definite diagnosis results from combined evidence of laboratory and instrumental data (degenerative changes in the lumbar spine, compressions, entrapments, etc.); 3) those in which the negative result of the investigations prevents a positive diagnosis and hence a presumptive etiology (spondylosis, inflammatory process, ischemia of the nerve) may be formulated. Attention is drawn to the favorable course of the condition in the patients of this group.
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PMID:Problems of etiology in femoral neuropathies. 298 53

We report a case of common peroneal mononeuropathy caused by an intraneural ganglion in a 9-year-old boy. The mass and the contiguous nerve fascicles were excised under the operating microscope. Histologically, the cyst wall was composed of layers of elongated cells merging with fascicles that exhibited changes suggestive of a pressure-ischemia effect. Electron microscopy showed that the cells forming cyst wall were myofibroblasts, similar to the cells found in ganglia arising from joints elsewhere in the body. A review of the English literature on intraneural ganglia discloses 44 additional cases, of which 86% involved the common peroneal nerve. The most common clinical feature was motor dysfunction (followed by pain, sensory loss, and the presence of a palpable mass), and a significant male predominance is noted. The pathogenesis of this nerve lesion is discussed in light of our findings.
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PMID:Intraneural ganglion: a case report with electron microscopic observations. 724 5

We present a patient with a clinical picture of multiple mononeuropathy in which muscle and sural nerve biopsy revealed the existence of vasculitis compatible with panarteritis nodosa. Along with classical axonal lesion signs, we observed multifocal conduction blocks (CB) in all the nerves explored electrophysiologically. Topographic evolution was atypical in that distal BC disappeared earlier, whereas proximal BC appeared later and in all cases persisted longer. Ischemia may play a pathogenic role in BC along with other more well-known factors such as compression and immunological processes. BC detection would probably be less exceptional if, when ischemic neuropathy is suspected, patients were subjected to early and follow-up electrophysiological exploration that included proximal nerve segments.
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PMID:[Ischemic neuropathy with conduction blocks]. 757 30

Lower extremity symptoms are caused by lesions at any level of the neuraxis, from cortex to muscle. HIV affects virtually every level of the nervous system, either directly or indirectly. The presence of pathology at multiple levels and by multiple processes further complicates the bedside diagnosis of a patient with AIDS and neurologic symptoms. Many neuropathies and other conditions that affect the lower extremities can be identified with careful history and physical examination, confirmed with limited testing, and can be treated successfully. Distal symmetric polyneuropathy is the most common lower extremity disorder, but it must be distinguished from similar-appearing neuropathies caused by medications, B12 deficiency, or vasculitis. Diffuse infiltrative lymphocytosis syndrome also causes a painful peripheral neuropathy that must be distinguished from distal symmetric polyneuropathy. Inflammatory demyelinating polyneuropathies are characterized by muscle weakness. They occur in early, asymptomatic HIV infection and respond to plasmapheresis or steroids. Mononeuropathies in patients with CD4 counts more than 200 often resolve on their own. Multiple mononeuropathies, which occur in patients with CD4 counts less than 50, are often associated with cytomegalovirus infection and may follow a rapidly progressive course unless treated promptly and aggressively. Progressive polyradiculopathy occurs late in the course of AIDS, is often caused by cytomegalovirus, is rapidly progressive, and generally is fatal unless recognized and treated promptly. Muscle weakness, myalgia, and fatigue are common in HIV and have multiple causes. Lower extremity spasticity may be caused by treatable etiologies such as spinal cord abscess, tumor, disc compression, B12 deficiency, or ischemia. Gait disturbances are common but nonspecific and may be caused by treatable neurologic disorders at any level of the neuraxis.
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PMID:Neurologic problems of the lower extremity associated with HIV and AIDS. 957 54

Systemic vasculitis occurs in a heterogeneous group of primary disorders or can be a manifestation of infection, an adverse drug reaction, malignancy or a connective tissue disease. A vasculitic process should be suspected in patients with unexplained ischemia or multiple organ involvement, especially when such features as polymyalgia rheumatica, inflammatory arthritis, palpable purpura, glomerulonephritis or multiple mononeuropathy are also present. The clinical features of systemic vasculitis depend on the organs involved and, in turn, organ involvement is largely influenced by the size of the affected blood vessels. The diagnostic work-up should be tailored to the clinical situation and geared toward a tissue or angiographic diagnosis, bearing in mind that the findings from these studies are not always pathognomonic. Emphasis should also be placed on exclusion of a secondary process. The diagnosis of the specific type of vasculitis may be made on the basis of the clinical features and the histopathologic or angiographic findings. Initial therapy for most types of systemic vasculitis consists of high-dose corticosteroids, with the addition of immunosuppressive therapy in certain patients.
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PMID:An approach to diagnosis and initial management of systemic vasculitis. 1052 86

Ischemic neuropathy from sources other than diabetes is less common, but can be encountered in clinical practice. Diagnosis can be challenging, and many patients may be referred to the electrodiagnostic laboratory. Overlapping mononeuritis multiplex is a common presentation, but distal symmetric polyneuropathy and monomelic neuropathy patterns can be seen. Depending on the disease associated with ischemic neuropathy, a mononeuropathy or a sensory-motor, axonal-demyelinating peripheral neuropathy may be seen as well. The treatment of ischemic neuropathy varies depending on the associated disease. Prognosis can be poor in the case of amyloidosis and the primary vasculitides. The literature is limited to cross-sectional case series and rare longitudinal studies likely related to the incidence of the diseases. Further study is needed to fully define the extent of the neurologic consequences of peripheral ischemia and its significance clinically.
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PMID:Ischemic peripheral neuropathy. 1134 13

Vasculitis typically affects the 50- to 400-micron vessels of the vasa nervorum, leading to randomly distributed ischemia along the course of the nerve. This, in turn, leads to a distinctive picture, multiple mononeuropathy, as a frequent but not invariant clinical consequence of vasculitis. The diagnosis of vasculitic neuropathy is usually made by biopsy histologic confirmation. The response to treatment varies among different vasculitides; vasculitis restricted to the peripheral nervous system is often especially responsive.
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PMID:Vasculitic neuropathies. 1172 62

Peripheral nerve involvement is a frequent complication of type 1 and type 2 diabetes, and can induce major disability. Almost all types of clinical or electrophysiological disturbances may be present: mononeuropathy involving cranial nerves or a limb; multiple mononeuropathy; proximal acute radiculopathy; distal, symmetric, sensory polyneuropathy; autonomic neuropathy. Physiopathology intricates probably several mechanisms but metabolic dysregulation and ischemia are mainly involved. Despite numerous controlled clinical trials no treatment has demonstrated efficacy for peripheral neuropathy, excepting the optimization of diabetes equilibrium. However, symptomatic treatments are available, particularly for the management of neuropathic pain.
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PMID:[Diabetic neuropathies]. 1179 22

Livedoid vasculitis is a chronic dermatological disorder associated with petechiae and recurrent, unusually shaped ulcers that heal to form hyperpigmentated areas and atrophie blanche. This condition is more correctly termed a vasculopathy, rather than a vascultis, and is often associated with an underlying hypercoagulable disorder. We report a patient with livedoid vasculitis and mononeuropathy multiplex. We propose that peripheral nervous system involvement arises from multifocal areas of ischemia due to fibrin and thrombin deposition within both the wall and lumen of vasa nervorum.
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PMID:Mononeuropathy multiplex in association with livedoid vasculitis. 1457 69


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