Purpose: To assess the duration and intensity of the changes appearing in laboratory values related to iron utilisation during viral infection.
Material and methods: With previous parental consent, 120 eutrophic infants received vaccination with attenuated measles virus or a combination of measles, mumps and rubella viruses as a model of mild viral infection. A number of laboratory tests were performed on day 0 and in two later occasions (4-21, 9-14 or 9-30); these included blood cell counts, ESR, serum iron, total iron binding capacity, transferrin saturation index, free erythrocytic protoporphyrin, serum ferritin, intra-erythrocytic ferritin, direct anti-human globulin test and C-reactive protein. The statistical analyses were done in accordance with ANOVA, Student's t test, Wilcoxon, Kruskall - Wallis, Mann-Whitney and Fisher methods.
Results: A significant haemoglobin drop was seen on days 9 and 14 post-vaccination. This descent was > 10 g/L in 8.2% of the cases, and > or = 6 g/L in 19.6%. Serum iron and transferrin saturation decreased significantly, whereas mean corpuscular volume, free erythrocyte protoporphyrin and serum ferritin were significantly increased. All these but protoporphyrin recovered by day 30. Subjects with normal iron metabolism figures on day 0 and those whose thermal variations were above 38 degrees C had greater changes in the figures related to iron metabolism.
Conclusion: The evaluation of iron metabolism is not reliable if the patient has suffered from infection, although a mild viral one, in the three weeks prior to the study.