Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment
OBJECTIVE: Parasites may recur asymptomatically after initial clearance by antimalarial treatment. Current guidelines recommend treatment only when patients develop symptoms or at the end of follow-up. We wanted to assess prospectively the probability of becoming symptomatic and the risks of this pr...
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okr-10986-51182021-04-23T14:02:21Z Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment Olliaro, P. Pinoges, L. Checchi, F. Vaillant, M. Guthmann, J. P. Antimalarials Preschool Child Female Humans Infant Logistic Models Malaria/*drug therapy/parasitology/*physiopathology/prevention & control Male Parasitemia control Proportional Hazards Models Recurrence Risk Factors OBJECTIVE: Parasites may recur asymptomatically after initial clearance by antimalarial treatment. Current guidelines recommend treatment only when patients develop symptoms or at the end of follow-up. We wanted to assess prospectively the probability of becoming symptomatic and the risks of this practice. METHODS: We analysed data collected in 13 trials of uncomplicated paediatric malaria conducted in eight sub-Saharan African countries. These studies followed all cases of post-treatment asymptomatic parasitaemia until they developed symptoms or to the end of the 28-day follow-up period, at which time parasite genotypes were compared to pre-treatment isolates to distinguish between recrudescences and new infections. RESULTS: There were 425 asymptomatic recurrences after 2576 treatments with either chloroquine, sulfadoxine/pyrimethamine or amodiaquine, of which 225 occurred by day 14 and 200 between day 15 and day 28. By day 28, 42% developed fever (median time to fever = 5 days) and 30% remained parasitaemic but afebrile, while 23% cleared their parasites (outcome unknown in 4%). Young age, parasitaemia >/=500 parasites/microl; onset of parasitaemia after day 14, and treatment with amodiaquine were the main variables associated with higher risk of developing fever. CONCLUSION: In areas of moderate to intense transmission, asymptomatic recurrences of malaria after treatment carry a substantial risk of becoming ill within a few days and should be treated as discovered. Young children are at higher risk. The higher risk carried by cases occurring in the second half of follow-up may be explained by falling residual drug levels. 2012-03-30T07:31:23Z 2012-03-30T07:31:23Z 2008 Journal Article Trop Med Int Health 1365-3156 (Electronic) 1360-2276 (Linking) http://hdl.handle.net/10986/5118 EN http://creativecommons.org/licenses/by-nc-nd/3.0/igo World Bank Journal Article |
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Antimalarials Preschool Child Female Humans Infant Logistic Models Malaria/*drug therapy/parasitology/*physiopathology/prevention & control Male Parasitemia control Proportional Hazards Models Recurrence Risk Factors |
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Antimalarials Preschool Child Female Humans Infant Logistic Models Malaria/*drug therapy/parasitology/*physiopathology/prevention & control Male Parasitemia control Proportional Hazards Models Recurrence Risk Factors Olliaro, P. Pinoges, L. Checchi, F. Vaillant, M. Guthmann, J. P. Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
relation |
http://creativecommons.org/licenses/by-nc-nd/3.0/igo |
description |
OBJECTIVE: Parasites may recur asymptomatically after initial clearance by antimalarial treatment. Current guidelines recommend treatment only when patients develop symptoms or at the end of follow-up. We wanted to assess prospectively the probability of becoming symptomatic and the risks of this practice. METHODS: We analysed data collected in 13 trials of uncomplicated paediatric malaria conducted in eight sub-Saharan African countries. These studies followed all cases of post-treatment asymptomatic parasitaemia until they developed symptoms or to the end of the 28-day follow-up period, at which time parasite genotypes were compared to pre-treatment isolates to distinguish between recrudescences and new infections. RESULTS: There were 425 asymptomatic recurrences after 2576 treatments with either chloroquine, sulfadoxine/pyrimethamine or amodiaquine, of which 225 occurred by day 14 and 200 between day 15 and day 28. By day 28, 42% developed fever (median time to fever = 5 days) and 30% remained parasitaemic but afebrile, while 23% cleared their parasites (outcome unknown in 4%). Young age, parasitaemia >/=500 parasites/microl; onset of parasitaemia after day 14, and treatment with amodiaquine were the main variables associated with higher risk of developing fever. CONCLUSION: In areas of moderate to intense transmission, asymptomatic recurrences of malaria after treatment carry a substantial risk of becoming ill within a few days and should be treated as discovered. Young children are at higher risk. The higher risk carried by cases occurring in the second half of follow-up may be explained by falling residual drug levels. |
format |
Journal Article |
author |
Olliaro, P. Pinoges, L. Checchi, F. Vaillant, M. Guthmann, J. P. |
author_facet |
Olliaro, P. Pinoges, L. Checchi, F. Vaillant, M. Guthmann, J. P. |
author_sort |
Olliaro, P. |
title |
Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
title_short |
Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
title_full |
Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
title_fullStr |
Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
title_full_unstemmed |
Risk Associated with Asymptomatic Parasitaemia Occurring Post-Antimalarial Treatment |
title_sort |
risk associated with asymptomatic parasitaemia occurring post-antimalarial treatment |
publishDate |
2012 |
url |
http://hdl.handle.net/10986/5118 |
_version_ |
1764394012070903808 |