Affiliations: St. Paul's Eye Unit, Royal Liverpool University
Hospital, Liverpool, UK | Instituto di Oftalmologia, Università Cattolica
del Sacro Cuore, Largo A. Gemelli, Roma, Italy | Blantyre Malaria Project, Queen Elizabeth Central
Hospital, Blantyre, Malawi | Malawi-Liverpool-Wellcome Trust Clinical Research
Programme, College of Medicine, Blantyre, Malawi | College of Osteopathic Medicine, Michigan State
University, East Lancing, Michigan, USA
Note: [] Correspondence: Caroline L. Southern, M.D., c/o Prof. Simon P.
Harding, St Paul's Eye Unit, Royal Liverpool University Hospital, Liverpool, L7
8XP, UK. Tel.: +44 151 706 2000; Fax: +44 151 706 5905/5861; E-mail: [email protected]
Abstract: We aimed to investigate the visual evoked potential (VEP) in
children unconscious with Plasmodium falciparum malaria, a common cause
of death in Africa. Flash VEPs were carried out in Malawi during one peak
malaria season. Children were included in the study if they had P.
falciparum malaria and reduced consciousness – Blantyre Coma Score (BCS) 4 or
less out of 5. Initial VEPs were performed after stabilising the patient and
commencing treatment. To investigate optimal VEP protocols, varying stimulus
parameters were tested. Where possible, VEPs were repeated daily until the
child recovered full consciousness (BCS 5). The initial traces of 40 children
were included in the study and serial traces were obtained in 30 of these. Mean
VEP latency was greater on admission than either on day 1 or at BCS 5 (paired
t-test, P < 0.05) for all test protocols. There was a
positive correlation between VEP latency on admission and parasite count and a
negative correlation with blood glucose on admission (Spearman's rank
correlation, P < 0.05 for all test protocols). Children with
severe P. falciparum malaria have delayed VEP responses and recovery
occurs in parallel with return to normal consciousness. VEP recordings are
quick and reproducible and may find a place in assessing levels of coma and
cerebral function in severe malaria.
Keywords: Coma, malaria, visual evoked potential, children