NEW OBSERVATIONS CONCERNING EOSINOPHILIA IN HAY FEVER

Exercise-induced bronchoconstriction. Seasonal variation in children with asthma and in those with rhinitis

Standardized exercise challenge tests, symptom scores and whole-blood eosinophil and basophil counts were made before and during the pollen season in 32 children suffering from hay fever (n = 16) or hay fever and asthma (n = 16). All participants developed rhinitis symptoms during the season. The hay fever group showed in addition a significant seasonal increase in cough score (but in no other asthma symptom) and in circulating eosinophils (P less than 0.01); mean exercise-induced bronchoconstriction (EIB) did not change despite a slight increase in a few subjects. The asthma group showed seasonal increases in EIB (P less than 0.001), asthma symptom score (P less than 0.002), and total eosinophil count (P less than 0.001). The increase in the latter was significantly higher (P less than 0.05) than that in the hay fever group. The relative basophil count remained unchanged in both groups. In conclusion, the hay fever group and the asthma group could be clearly distinguished with respect to EIB during natural pollen exposure. The significantly higher increases in EIB and circulating eosinophils observed in the asthma group might possibly be due to greater pollen antigen sensitivity in the asthmatics.

Bone-marrow eosinophilia in the mouse. I. Eosinophil leukocyte levels in untreated mice

The number of eosinophil leukocytes in the bone marrow of untreated mice (Cpb:SE) has been shown to vary widely. A systematic investigation of this variability is reported here. The study was done a) within a group of mice, b) within groups of mice at roughly 3-month intervals, and c) within a group over a time course. The following are the most important results of this study: 1. Analysis of variance of eosinophils/1000 cells in 165 mice over a 35-day period showed that the results were consistent with the assumption that there are no changes during this interval (P is less than 0.05). 2. The number of eosinophils/1000 cells found in the various groups are not directly comparable; the mean number for the four groups investigated at intervals of about 3 months differed by a factor of up to 3. 3. On the basis of the variability found, the number of eosinophils/1000 cells in the bone marrow of a given untreated mouse in a group to be investigated cannot be reliably predicted. At a 99 per cent confidence level, the value would lie between 5 and 139.