Investigators from National University Hospital, Singapore, review the clinical features of 13 cases of pharyngeal-cervical-brachial (PCB) variant of Guillain-Barre syndrome (GBS) and outline new diagnostic criteria. In a series of 100 patients with PCB reported previously from Japan  the age of onset ranged from 5-83 years (median age 43), antecedent upper respiratory tract infections and diarrhea occurred in 71% and 30%, respectively (similar to GBS), and 31% had serological evidence of Campylobacter jejuni infection. Cytomegalovirus, Epstein-Barr virus, Mycoplasma pneumoniae and Hemophilus influenzae were associated infrequently (6-1%). PCB is defined as ‘pure’ in patients presenting with rapidly progressive oropharyngeal and cervicobrachial weakness associated with areflexia/hyporeflexia but without ophthalmoplegia or leg weakness . In contrast, some recent series describe sensory disturbance in the upper limbs, and normal or exaggerated reflexes. GBS forms a continuum of overlapping syndromes, those cases with ophthalmoplegia and ataxia overlapping with Fisher syndrome. One half of patients with PCB carry IgG anti-GT1a antibodies that cross-react with GQ1b, whereas most patients with Miller Fisher syndrome carry IgG and GQ1b antibodies that always cross-react with GT1a. Significant overlap between the clinical and serological profiles of these syndromes suggests a PCB/Fisher syndrome continuous spectrum. The neurophysiological findings in PCB are axonal rather than demyelinating. Myasthenia gravis, botulism and other myopathic disorders are differentiated from PCB by the absence of sensory deficits or areflexia. 
COMMENTARY. The diagnostic criteria for PCB variant of GBS include: 1) symmetric oropharyngeal weakness, arm weakness and areflexia/hyporeflexia; 2) absence of leg weakness, ataxia and disturbed consciousness; and 3) 12hr-28day intervalbetween onset and weakness. Supportive findings include: antecedent infection, CSF albumino-cytological dissociation, neurophysiological evidence of neuropathy, and presence of IgG anti-GT1a or anti-GQ1b antibodies. Brain MRI may be indicated to exclude brainstem ischemia, inflammation or brain tumor.