"My understanding of this disorder (eczema) is not good,
and the older I grow the more acutely I realize my ignorance"1
Lewis Webb Hill (1889-1968)
We are thankful to doctors Flohr and Williams for their thoughtful comments on our article2, which we welcome as the beginning of long overdue discussion about ISAAC studies. Our discussants suggested a possible problem with the Polish translation of the word "eczema". We are aware of previous errors resulting from inaccurate translations of the ISAAC questionnaire3, however, the word "wyprysk" used in the Polish translation has exactly the same meaning as, and can only translate back to the English (and Latin) word "eczema". Instead, we see a major problem with the definition and understanding of the term "eczema" itself, which unfortunately is not limited to lay persons: A prominent German dermatologist, Heinrich Adolf Gottron (1890-1974) once stated pertinently "Everyone knows how eczema looks like, yet no one knows what eczema is", which seemingly might be interpreted in favour of self-administered questionnaire studies, but only under a rather disputable assumption that there is only one kind of eczema. Indeed, in the original ISAAC publication4 the word "eczema" is taken for a synonym to medical diagnosis "atopic eczema" ("atopic dermatitis"). There is, however, a considerable danger connected with such oversimplification, as there are many forms of eczema that are not equivalents of atopic eczema, e.g. hand eczema, allergic or irritant contact eczema, seborrhoeic eczema, dyshidrotic eczema, etc. Due to their prevalence, these diagnoses may be known to many lay persons, however, one can hardly expect that parents filling in the ISAAC questionnaire will know the differences and guess correctly which particular kind of eczema is subject of this study. This might be the reason of the limited predictive value and poor correlation between responses to the ISAAC questionnaire and the medical examination that was observed in previous studies5,6. Our discussants further suggested that we would have diagnosed allergic contact dermatitis (ACD) in every child with a positive patch test. As a matter of fact, the diagnosis of ACD was based upon a thorough collective medical examination by a pediatrician-allergist and a dermatologist-allergist, with the patch test result being one of many criteria taken into account. A quick look into the paragraph "Patients and Methods" and Table 1 showing frequencies of positive patch tests and the final diagnoses, should dissipate any doubts with this regard. Taking positive patch test result for the diagnosis of ACD would be as erroneous as drawing conclusions about medical diagnoses from self-administered questionnaires. In conclusion, the present, as well as previous studies7,8 demonstrate that "eczema" detected with the ISAAC questionnaire can not be regarded as an equivalent to the diagnosis of atopic eczema, because of lacking possibility to differentiate between various eczemas and other chronic dermatoses that may be found in children. Only well-designed studies based upon undisputable criteria - medical history, allergy tests and a thorough clinical examination with differential diagnosis by a doctor could provide credible data on the prevalence of particular kinds of eczema in children.
- Hill LW. The importance of contact eczema in children. Pediatrics 1959; 23: 797-801.
- Czarnobilska E, Obtulowicz K, Dyga W, Spiewak R. A half of schoolchildren with "ISAAC eczema" are ill with allergic contact dermatitis. J Eur Acad Dermatol Venereol 2011, in print
- Miyake Y, Ohya Y, Sasaki S et al. Was the prevalence of Japanese childhood atopic eczema symptoms overestimated in the ISAAC study? J Allergy Clin Immunol 2004; 113: 571-2.
- Asher MI, Keil U, Anderson HR et al. International Study of Asthma and Allergies in Childhood (ISAAC): rationale and methods. Eur Respir J 1995; 8: 483-91.
- Flohr C, Weinmayr G, Weiland SK et al. How well do questionnaires perform compared with physical examination in detecting flexural eczema? Findings from the International Study of Asthma and Allergies in Childhood (ISAAC) Phase Two. Br J Dermatol 2009; 161: 846-53.
- Haileamlak A, Lewis SA, Britton J et al. Validation of the International Study of Asthma and Allergies in Children (ISAAC) and UK criteria for atopic eczema in Ethiopian children. Br J Dermatol 2005; 152: 735-41.
- Czarnobilska E, Obtulowicz K, Dyga W et al. Contact hypersensitivity and allergic contact dermatitis among schoolchildren and teenagers with eczema. Contact Dermatitis 2009; 60: 264-9.
- Czarnobilska E, Obtulowicz K, Dyga W et al. The most important contact sensitizers in Polish children and adolescents with atopy and chronic recurrent eczema as detected with the extended European Baseline Series. Pediatr Allergy Immunol 2011; 22: 252-6.
Patch testing for contact allergy in Krakow (Cracow), Poland
Photoallergy and Photopatch Test Course on DVD