Pathology of the motor-sensory axonal Guillain-Barr� syndrome (original) (raw)
Related papers
Axonal Guillain-Barré syndrome: a critical review
Acta Neurologica Scandinavica, 2001
Axonal Guillain±Barre  Syndrome (GBS) was ®rst described by Feasby et al. in 1986, challenging the existent notion of GBS being a primarily demyelinating disease. The severe course and slow recovery commonly seen in these patients was ascribed to axonal degeneration. Other authors challenged this claim on several grounds. Amidst these controversies, epidemics of a similar illness were reported from China, which were given the acronym AMAN, having exclusive motor involvement in contrast to the cases already described in which both motor and sensory involvement were present (AMSAN). Pathologically, Wallerian degeneration, minimal lymphocytic response, absent demyelination or in¯ammation and periaxonal macrophages are prominent features. Ultrastructural studies have revealed node of Ranvier to be the prime target of immune attack. A frequent occurrence of antecedent Campylobacter jejuni infection and a strong association between elevated titres of IgG GM1 and axonal GBS on a background of preceding C. jejunii infection has been observed and molecular mimicry between lipopolysaccharides of C. jejuni and neural epitopes has been proposed as a mechanism of injury. Clinically axonal variant is similar to AIDP, but a more severe course, with frequent respiratory involvement, ventilator dependence and signi®cant residue may be seen. Diagnosis is essentially electrophysiological. Treatment is similar to AIDP, preferential bene®t of either IVIG or plasmapheresis needs to be further evaluated. A critical review of existing literature in axonal GBS is presented.
Early nodal changes in the acute motor axonal neuropathy pattern of the Guillain-Barré syndrome
Journal of Neurocytology, 1996
The axonal patterns of Guillain-Barr6 syndrome, associated in many cases with antecedent Campylobacter jejuni infection, are now recognized as frequent causes of acute flaccid paralysis in some regions of the world. This study examined ultrastructurally the PNS of seven cases of the acute motor axonal neuropathy form of Guillain-Barr6 syndrome. In this disorder previous studies of advanced cases have found Wallerian-like degeneration of motor fibres in the spinal roots and peripheral nerves, with little lymphocytic inflammation or demyelination. The present study was focused on identifying early changes and establishing the sequence of changes. By electron microscopy the earliest and mildest changes consisted of lengthening of the node of Ranvier with distortion of the paranodal myelin, and in some instances with breakdown of the outermost myelin terminal loops. At this stage many nodes had overlying macrophages which extended their processes through the Schwann cell basal lamina covering the node and apposed the axolemma. Macrophage processes then extended beneath the myelin terminal loops, and the whole macrophage entered the periaxonal space at the paranode. Macrophage processes dissected the axon from the adaxonal Schwann cell plasmalemma and the macrophages advanced into the internodal periaxonal space, where they typically surrounded a condensed-appearing axon. At this stage the adaxonal Schwann cell cytoplasm regularly degenerated and disappeared, so that the periaxonal space was bounded by the innermost myelin lamella, and the axolemma of many fibres could not be seen. The internodal myelin sheath and the abaxonal Schwann cell cytoplasm remained normal. This arrangement appeared to be stable for some time, but in many fibres the axon subsequently underwent Wallerian-like degeneration. By interfering with impulse conduction, these nodal and periaxonal changes may explain paralysis in some pathologically mild cases. In addition, at early stages, these changes may be reversible, thus explaining the rapid recovery of some patients who become paralysed with acute motor axonal neuropathy. These observations, taken together with previous studies, suggest that acute motor axonal neuropathy is an antibody-and complement-mediated disorder in which the relevant epitopes are present on the nodal and internodal axolemma. neuropathy (AMAN) (Goldstein et al.
Axonal Guillain-Barré syndrome: concepts and controversies
The Lancet Neurology, 2013
Acute motor axonal neuropathy (AMAN) is a pure motor axonal subtype of Guillain-Barré syndrome (GBS) that was identifi ed in the late 1990s. In Asia and Central and South America, it is the major subtype of GBS, seen in 30-65% of patients. AMAN progresses more rapidly and has an earlier peak than demyelinating GBS; tendon refl exes are relatively preserved or even exaggerated, and autonomic dysfunction is rare. One of the main causes is molecular mimicry of human gangliosides by Campylobacter jejuni lipo-oligosaccharides. In addition to axonal degeneration, electrophysiology shows rapidly reversible nerve conduction blockade or slowing, presumably due to pathological changes at the nodes or paranodes. Autoantibodies that bind to GM1 or GD1a gangliosides at the nodes of Ranvier activate complement and disrupt sodium-channel clusters and axoglial junctions, which leads to nerve conduction failure and muscle weakness. Improved understanding of the disease mechanism and pathophysiology might lead to new treatment options and improve the outlook for patients with AMAN.
Annals of Neurology, 2000
To clarify the relations of the axonal form of Guillain-Barré syndrome (GBS) to anti-ganglioside antibodies and Campylobacter jejuni infection, 86 consecutive Japanese GBS patients were studied. Electrodiagnostic criteria showed acute inflammatory demyelinating polyneuropathy in 36% of the patients and acute motor axonal neuropathy (AMAN) in 38%. Frequent anti-ganglioside antibodies were of the IgG class and against GM1 (40%), GD1a (30%), GalNAc-GD1a (17%), and GD1b (21%). Identified infections were C. jejuni (23%), cytomegalovirus (10%), Mycoplasma pneumoniae (6%), and Epstein-Barr virus (3%). There was a strong association between AMAN and IgG antibodies against GM1, GD1a, GalNAc-GD1a, or GD1b. Almost all the patients with at least one of these antibodies had the AMAN pattern or rapid resolution of conduction slowing/block possibly because of early-reversible changes on the axolemma. C. jejuni infection was frequently associated with AMAN or anti-ganglioside antibodies, but more than half of the patients with AMAN or anti-ganglioside antibodies were C. jejuni-negative. These findings suggest that the three phenomena "axonal dysfunctions (AMAN or early-reversible conduction failure)," "IgG antibodies against GM1, GD1a, GalNAc-GD1a, or GD1b," and "C. jejuni infection" are closely associated but that microorganisms other than C. jejuni frequently trigger an anti-ganglioside response and elicit axonal GBS.
Axonal Guillain–Barré syndrome associated with axonal Charcot–Marie–Tooth disease
Journal of the Neurological Sciences, 2003
We report the first case of axonal Guillain -Barré syndrome (GBS) associated with axonal Charcot -Marie -Tooth disease (CMT). A 30year-old Japanese man, who had suffered leg atrophy and foot deformity since childhood, developed acute weakness in his four limbs following an upper respiratory tract infection. Nerve conduction studies showed low compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes in all the nerves tested. Serial studies showed a rapid increase in CMAP amplitude, but no significant change in SNAP, which indicates that the acute event selectively involved motor axons and was superimposed on a baseline motor -sensory axonal neuropathy, probably CMT Type 2. Elevated serum IgG antibodies against GM1 and GM1b, an increase in CSF protein, and rapid clinical and electrophysiological recovery after plasma exchange support the diagnosis of a pure motor axonal form of GBS, acute motor axonal neuropathy. The association may be coincidental, but a particular susceptibility to axonal damage of CMT2 cannot be excluded. D
Journal of the Peripheral Nervous System, 2009
We describe a clinicopathological study of a patient presenting with severe and electrophysiological axonal Guillain-Barré syndrome (GBS). An 83-year-old man had a 2-day history of distal acroparesthesias and ascending weakness culminating in quadriplegia, the patient dying 1 month after onset. On day 3, motor conduction velocity (MCV) and distal motor latency values were normal or minimally delayed; most F waves were present with latencies normal or barely delayed. Compound muscle action potential (CMAP) amplitudes were variably reduced. On day 10, there was reduction of CMAPs with relative preservation of MCV. On histological study, the density of myelinated fibers was normal in L5 ventral and dorsal roots, where outstanding lesions included dark fibers, scattered macrophage infiltration, and occasional images of de-remyelination or axonal degeneration. In the fifth spinal nerve, there was widespread loss of myelinated fibers with focal areas showing almost complete fiber loss and variable fascicular combination of extensive de-remyelination and axonal degeneration. Wallerian-like degeneration predominated in femoral and sciatic nerves. Peripheral neuron cell bodies showed central chromatolysis. We conclude that the pathological hallmark of this electrophysiological axonal GBS case is extensive but variable de-remyelination of proximal nerve trunks with superimposed nerve ischemia and axonal degeneration.
Differences in membrane properties of axonal and demyelinating Guillain-Barr� syndromes
Annals of Neurology, 2002
Guillain-Barré syndrome is classified into acute motor axonal neuropathy (AMAN) and acute inflammatory demyelinating polyneuropathy (AIDP) by electrodiagnostic and pathological criteria. In AMAN, the immune attack appears directed against the axolemma and nodes of Ranvier. Threshold tracking was used to measure indices of axonal excitability (refractoriness, supernormality, and threshold electrotonus) for median nerve axons at the wrist of patients with AMAN (n ؍ 10) and AIDP (n ؍ 8). Refractoriness (the increase in threshold current during the relative refractory period) was greatly increased in AMAN patients, but the abruptness of the threshold increases at short interstimulus intervals indicated conduction failure distal to the stimulation (ie, an increased refractory period of transmission). During the 4 week period from onset, the high refractoriness returned toward normal, and the amplitude of the compound muscle action potential increased, consistent with improvement in the safety margin for impulse transmission in the distal nerve. In contrast, refractoriness was normal in AIDP, even though there was marked prolongation of distal latencies. Supernormality and threshold electrotonus were normal in both groups of patients, suggesting that, at the wrist, membrane potential was normal and pathology was relatively minor. These results support the view that the predominantly distal targets of immune attack are different for AMAN and AIDP. Possible mechanisms for the reduced safety factor in AMAN are discussed.
Hyperreflexia in axonal Guillain–Barré syndrome subsequent to Campylobacter jejuni enteritis
Journal of the Neurological Sciences, 2002
We describe a patient with the acute motor axonal neuropathy (AMAN) form of Guillain -Barré syndrome (GBS), who showed generalized hyperreflexia. A 24-year-old man developed acute paralysis following Campylobacter jejuni enteritis. He showed exaggerated tendon reflexes with abnormal reflex spread to other segments, and was initially diagnosed as having post-infectious myelitis. Nerve conduction studies showed motor axonal degeneration (the AMAN pattern), and increased soleus H-reflex amplitudes. His serum was positive for IgG antibodies to gangliosides GM1b and GalNAc-GD1a. He was treated with plasmapheresis, resulting in rapid recovery. Hyperreflexia was still present 12 months after onset when muscle strength was completely normal. This case provides further evidence that patients with AMAN can develop increased motor neuron excitability, and possible mechanisms for the hyperreflexia are discussed. D
Anti-GD1a antibody is associated with axonal but not demyelinating forms of Guillain-Barr� syndrome
Annals of Neurology, 1999
Immunopathological studies suggest that the target of immune attack is different in the subtypes of Guillain-Barré syndrome (GBS). In acute motor axonal neuropathy (AMAN), the attack appears directed against the axolemma and nodes of Ranvier. In acute inflammatory demyelinating polyneuropathy (AIDP), the attack appears directed against a component of the Schwann cell. However, the nature of the antigenic targets is still not clear. We prospectively studied 138 Chinese GBS patients and found that IgG anti-GD1a antibodies were closely associated with AMAN but not AIDP. With a cutoff titer of greater than 1:100, 60% of AMAN versus 4% of AIDP patients had IgG anti-GD1a antibodies; with a cutoff titer of greater than 1:1,000, 24% of AMAN patients and none of the AIDP patients had IgG anti-GD1a antibodies. In contrast, low levels of IgG anti-GM1 antibodies (>1:100) were detected in both the AMAN and the AIDP forms (57% vs 35%, NS). High titers of IgG anti-GM1 (>1:1,000) were more common in the AMAN form (24% vs 8%, NS). Serological evidence of recent Campylobacter infection was detected in 81% of AMAN and 50% of AIDP patients, and anti-ganglioside antibodies were common in both Campylobacter-infected and noninfected patients. Our results suggest that IgG anti-GD1a antibodies may be involved in the pathogenesis of AMAN.