[Anti-GQ1b syndrome. A child with Miller-Fisher-Bickerstaff syndrome].

Miller-Fisher syndrome and Bickerstaff brainstem encephalitis, among others, constitute the anti-GQ1b syndrome, with a common immune pathophysiologic pathway characterized by the presence of anti-GQ1b antibodies, which react against the different nervous system GQ1b sites according to their different accessibility. The Miller-Fisher syndrome has a prevalence of 0.09 cases per 100 000 people-year but there are not epidemiological studies about Bickerstaff brainstem encephalitis, that it seems to be less frequent.

[Cyanosis in 14-year-old patient. Methemoglobinemia: case report].

The bluish coloration of skin and mucous membranes, called as cyanosis, could be explained by high reduced hemoglobin in the capillaries, or the presence of elevated methemoglobin concentration. It is important to think of methemoglobinemia as a differential diagnosis in a cyanotic patient who does not respond to oxygen administration once cardiorespiratory causes are discarded; since it requires other diagnostic methods and specific treatment. We described a case of cyanosis in a fourteen-year-old adolescent with probable congenital methemoglobinemia.