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Prevalence of dichromate sensitivity
VOLUME 67 NUMBER 4
Abstracts
nonspecific hyperreactivity on antigen-induced bronchonconstriction. An inbred strain of rats was developed that showed maximal or even exag+ated bronchnconstrictiqn when they were challenged with aerosolized egg-albumin antigen. Findings in these animals were compared to those made on similarly treated Fischer strain rats that fail to become dyspneic when they are challenged with antigen and to sensitized Sprague-Dawley rats that respond in a heterogeneous pattern to aerosolized antigen challenge. Tracheal ring chains and lung strips taken from freshly killed animals were suspended in buffered indomethacincontaining medium and challenged with methacoline, and tension was measured via strain gauge. After adequate washing, the tissue was challenged with serotonin and leukotrienes. The contractile response was expressed as a percentage of that elicited by the original methacholine challenge. In addition, live, egg-sensitized animals from all three groups were tested in vivo by pneumotachygraph for the respiratory response to aerosolized mediators as well as to intravenous serotonin. Pulmonary resistance (R# and dynamic compliance (Cdyn) were derived after challenge with aerosolized serotonin or LTD,. The inbred rat tracheal ring musculature responded in vitro to serotonin and methacholine but not to leukotrienes of histamine. The lung parenchymal strips constricted in the presence of serotonin, methacholine, and leukotriene. The in vivo experiments demonstrated bronchopulmonary reactivity in the inbred rats after aerosol challenge with serotonin, histamine, methacholine, and LTD,. Fischer rats responded poorly to the various challenges, whereas the Sprague-Dawley rats reacted to a lesser degree than did the inbred strain. It is concluded that sensitized tracheal and pulmonary smooth muscle responses to antigen are enhanced by mediators that are released during the antigen-antibody (IgE) reaction in animals that hyperrespond to antigen challenge. The potential importance of this animal model to the study of human asthma is mentioned. D.S.
Miscellaneous Prevalence Peltonen
allergies
of dichromate
L, Fraki
J:
Contact
sensitivity Dermatitis
9:190,
1983.
The authors of this article believe that the commonest cause of occupational eczema in Finland is chromate sensitivity (CS). Prevalence of CS in (I) an unselected population without known occupational exposure to dichromate, (2) a group of employees exposed to industrial chromium, and (3) dermatitis patients tested in a clinic was studied, and possible correlation between chromate sensitivity and occupation was sought. Group 1 consisted of 822 healthy adult volunteers. It was found that 2% of the 410 men and 1.5% of the 412 women in this grouj, had a positive patch test reaction to 0.5% potassium dichromate. However, most of the positive reactions (lo/ 14) occurred in a subgroup of 110 offset printers,
15
lithographers, and printing-plant cleaners who normally have occupational exposure to Cr. Among the remaining test population, sensitivity to dichromate was rare. Of the 14 C% persons, nine had present or past hand eczema, two had ezcema of the face only, and three could not recall having had any skin trouble. Group 2 clinic patients consisted of 298 1 individuals tested during a 5-year period. CS occurred in 6.8% of the men and 2.8% in women; however, in a subgroup of 499 patients with occupational hand eczema, there was a 20% positive rate in men and 8% in women that demonstrated CS is found more frequently in men engaged in the building and graphics industries but is present also in workers engaged in the radio and TV industry. Among women, CS was more common in those working in leather tanning and engineering trades. CS caused by exposure to detergents and bleaching agents reported to be frequent in women in other countries appeared to be uncommon in these groups of patients. A.J.C.
Pediatrics Does infant allergy?
feeding
Burr
Dis
M:
Arch
Child
affect the risk of 58:561,
1983.
This article reviews 24 studies of varying design and quality that examine the question of whether withholding cows’ milk (CM) from babies reduces the risk of allergic disease (AD). Prospective observational studies in which infants were not selected by medical history and others in which infants were selected by medical history, retrospective studies, random controlled trials, and other studies representing a compromise between observational and intervention methods were reviewed. Thirteen of the 24 studies found a positive association between AD and CM or mixed feeding in early infancy. In one study, AD was associated positively with breast feeding, whereas 10 studies demonstrated no convincing relationship with CM infant feeding and AD. The author points out that the 24 studies differ in size and quality, and their results should not be given equal weight. For example, in very few studies was a clinical assessment carried out “blind” with regard to the feeding history so that some bias may have affected the findings unintentionally. Indeed, mothers with an allergic family history who believe that cows’ milk increases the risk of AD automatically tend to avoid CM for their babies. Another serious defect in many of the studies was failure to monitor early supplementary feeds in breast-fed infants since it is believed likely that even small amounts of a food such as CM could influence the development of allergy. Another reservation cited by the author is that in many of these studies relevant information was obtained from mothers long after feedings, with intervals of 6 wk. 3 mo, 6 mo, and even several years in different studies. It is concluded that while the issue is not settled, the balance of evidence tends to favor the hypothesis that feed-
Abstracts
nonspecific hyperreactivity on antigen-induced bronchonconstriction. An inbred strain of rats was developed that showed maximal or even exag+ated bronchnconstrictiqn when they were challenged with aerosolized egg-albumin antigen. Findings in these animals were compared to those made on similarly treated Fischer strain rats that fail to become dyspneic when they are challenged with antigen and to sensitized Sprague-Dawley rats that respond in a heterogeneous pattern to aerosolized antigen challenge. Tracheal ring chains and lung strips taken from freshly killed animals were suspended in buffered indomethacincontaining medium and challenged with methacoline, and tension was measured via strain gauge. After adequate washing, the tissue was challenged with serotonin and leukotrienes. The contractile response was expressed as a percentage of that elicited by the original methacholine challenge. In addition, live, egg-sensitized animals from all three groups were tested in vivo by pneumotachygraph for the respiratory response to aerosolized mediators as well as to intravenous serotonin. Pulmonary resistance (R# and dynamic compliance (Cdyn) were derived after challenge with aerosolized serotonin or LTD,. The inbred rat tracheal ring musculature responded in vitro to serotonin and methacholine but not to leukotrienes of histamine. The lung parenchymal strips constricted in the presence of serotonin, methacholine, and leukotriene. The in vivo experiments demonstrated bronchopulmonary reactivity in the inbred rats after aerosol challenge with serotonin, histamine, methacholine, and LTD,. Fischer rats responded poorly to the various challenges, whereas the Sprague-Dawley rats reacted to a lesser degree than did the inbred strain. It is concluded that sensitized tracheal and pulmonary smooth muscle responses to antigen are enhanced by mediators that are released during the antigen-antibody (IgE) reaction in animals that hyperrespond to antigen challenge. The potential importance of this animal model to the study of human asthma is mentioned. D.S.
Miscellaneous Prevalence Peltonen
allergies
of dichromate
L, Fraki
J:
Contact
sensitivity Dermatitis
9:190,
1983.
The authors of this article believe that the commonest cause of occupational eczema in Finland is chromate sensitivity (CS). Prevalence of CS in (I) an unselected population without known occupational exposure to dichromate, (2) a group of employees exposed to industrial chromium, and (3) dermatitis patients tested in a clinic was studied, and possible correlation between chromate sensitivity and occupation was sought. Group 1 consisted of 822 healthy adult volunteers. It was found that 2% of the 410 men and 1.5% of the 412 women in this grouj, had a positive patch test reaction to 0.5% potassium dichromate. However, most of the positive reactions (lo/ 14) occurred in a subgroup of 110 offset printers,
15
lithographers, and printing-plant cleaners who normally have occupational exposure to Cr. Among the remaining test population, sensitivity to dichromate was rare. Of the 14 C% persons, nine had present or past hand eczema, two had ezcema of the face only, and three could not recall having had any skin trouble. Group 2 clinic patients consisted of 298 1 individuals tested during a 5-year period. CS occurred in 6.8% of the men and 2.8% in women; however, in a subgroup of 499 patients with occupational hand eczema, there was a 20% positive rate in men and 8% in women that demonstrated CS is found more frequently in men engaged in the building and graphics industries but is present also in workers engaged in the radio and TV industry. Among women, CS was more common in those working in leather tanning and engineering trades. CS caused by exposure to detergents and bleaching agents reported to be frequent in women in other countries appeared to be uncommon in these groups of patients. A.J.C.
Pediatrics Does infant allergy?
feeding
Burr
Dis
M:
Arch
Child
affect the risk of 58:561,
1983.
This article reviews 24 studies of varying design and quality that examine the question of whether withholding cows’ milk (CM) from babies reduces the risk of allergic disease (AD). Prospective observational studies in which infants were not selected by medical history and others in which infants were selected by medical history, retrospective studies, random controlled trials, and other studies representing a compromise between observational and intervention methods were reviewed. Thirteen of the 24 studies found a positive association between AD and CM or mixed feeding in early infancy. In one study, AD was associated positively with breast feeding, whereas 10 studies demonstrated no convincing relationship with CM infant feeding and AD. The author points out that the 24 studies differ in size and quality, and their results should not be given equal weight. For example, in very few studies was a clinical assessment carried out “blind” with regard to the feeding history so that some bias may have affected the findings unintentionally. Indeed, mothers with an allergic family history who believe that cows’ milk increases the risk of AD automatically tend to avoid CM for their babies. Another serious defect in many of the studies was failure to monitor early supplementary feeds in breast-fed infants since it is believed likely that even small amounts of a food such as CM could influence the development of allergy. Another reservation cited by the author is that in many of these studies relevant information was obtained from mothers long after feedings, with intervals of 6 wk. 3 mo, 6 mo, and even several years in different studies. It is concluded that while the issue is not settled, the balance of evidence tends to favor the hypothesis that feed-