Frequency of X-linked ichthyosis in coastal southern Italy: a study on a representative sample of a young male population.

BACKGROUND: No reports on the frequency of X-linked ichthyosis (XLI) in the Italian general population and few surveys on the frequency of XLI in large communities in the world are available. OBJECTIVE: The aim of this study was the assessment of the frequency of XLI in a large representative sample of the Italian male population. SUBJECTS AND METHODS: This study involved young men who enlisted as conscripts in the Italian Navy from January 1998 through February 2002, examined, prior to enlistment, at the Draft Council's Medical Unit of the Italian Navy in Taranto, Italy, to evaluate their psychophysical fitness. All the patients with an ichthyosiform condition were referred to the Department of Dermatology of the Navy Hospital, underwent a thorough dermatological examination and completed a questionnaire regarding their personal and familial history. Pertinent results of the other clinical investigations were recorded and the final diagnosis was formulated on the basis of all these data. RESULTS: From January 1998 through February 2002, of 75,653 young men examined, 15 cases of XLI were diagnosed, with a frequency of 1:5,043 or 1.98 per 10,000 (95% confidence interval based on the Poisson distribution 1.01-2.90). Four out of 15 cases (26.6%) showed corneal opacities. No other significant associated pathological change was observed. CONCLUSIONS: As this study is a survey involving a large male sample, homogeneous with reference to age, race and country of origin (southern Italy), the frequency of XLI could be estimated at about 1.98 per 10,000 males. These data are roughly in agreement with estimates from other European surveys.

Adult-onset atopic dermatitis in a patch test population.

BACKGROUND: Epidemiological studies about atopic dermatitis (AD) almost exclusively relate to childhood disease with little mention of adult-onset disease. In clinical practice, however, patients who have AD and in whom the onset of disease occurs in adult life are sometimes seen. OBJECTIVE: Because the subjects with a chronic and recalcitrant eczema are frequently patch tested, the aim of this study was to evaluate the prevalence of adult-onset AD in a patch test population and the differences existing between the early- and adult-onset subsets. METHODS: This retrospective analysis was performed on 502 adults (458 males, 44 females) affected by eczematous dermatitis, consecutively examined in the Department of Dermatology of the Italian Navy Hospital in Taranto. In this department, all the eczematous subjects are routinely submitted to the following tests: standard series (GIRDCA or SIDAPA with integrative haptens), prick test with environmental aeroallergens and common food allergens and dosage of total serum IgE. If it is required, additional series of patch tests are also applied. Many patients are also submitted to the atopy patch test (APT) with whole bodies of house dust mites at a concentration of 20%. In the AD patients, diagnosed according to the criteria of Hanifin and Rajka, the ages of onset were subdivided into the following categories: infancy (0-3 years); childhood (4-11 years); adolescence (> or =12 years). We arbitrarily also used the age of 18 years as the cut-off mark to allocate the patients to the adult-onset group (AOG) and defined as early-onset group (EOG) the cases encompassed in the aforesaid categories (i.e. onset < or =17 years). RESULTS: 8.8% of all eczemas were adult-onset ADs. 28 (5.6% of all eczemas) adult-onset ADs were 'sole' ADs, while 22 cases (3.2% of all eczemas) were adult-onset ADs in which a contact sensitization was detected. The mean SCORAD indexes, according to the age-of-onset groups, decreased when the age of onset increased. No statistical difference was detected between the EOG and AOG with regard to true contact sensitization, clinically relevant or non-relevant contact sensitization, prevalence of 'pure' AD and 'mixed' AD, and outcome of the APT. The hands were the most frequently affected site in the AOG. CONCLUSION: A small but significant number of patch-test-negative eczematous cases could be adult-onset ADs and, in this instance, the other two allergological tests (i.e. prick tests and dosage of total serum IgE) and an accurate evaluation according to stated clinical criteria should be performed. However, other studies on large series of patients are required to confirm our observation.