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C Chieregato

Publications and source records attributed to C Chieregato.

14 recordsLinked to original sources

Demodicidosis in immunocompetent young children: report of eight cases.

Demodex folliculorum and Demodex brevis are obligate parasites of the human pilosebaceous unit. They are the most common permanent ectoparasites in adults, but their incidence on children's skin is rare. Only few cases of demodicidosis have been reported in children aged below 5 years and most of them were suffering from leukemia or HIV infection. The aim of this study is to describe demodicidosis in young immunocompetent children. The clinical details of 8 healthy children are given. There were 4 males and 4 females aged between 10 months and 5 years referred to us for evaluation of a facial eruption characterized by erythema, papulopustules and variable edema. In 7 of these patients, skin scrapings were performed and in 1 a 4-mm punch biopsy. Numerous D. folliculorum were found in skin scrapings of 7 cases and at a histologic examination of skin biopsy in 1 case. We employed topical metronidazole gel 1% in all patients and we obtained a 100% recovery without relapses after a 1- to 3-year follow-up. In 2 of our cases Demodex infestation had a mild form resembling pityriasis folliculorum and the other cases presented a rosacea-like form. The reason why these young immunocompetent children developed demodicidosis is still under evaluation and investigation.

Child, Preschool

Sunscreen sensitization: a three-year study.

BACKGROUND: In the last decade UV filters have been incorporated in a large number of cosmetic products. OBJECTIVE: The purpose of our study was to evaluate the prevalence of sunscreen allergy in patients with a suspected photodermatitis. METHODS: 108 patients were patch-tested with the Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali (GIRDCA) standard series and photopatch-tested with the photopatch series. RESULTS: Allergy and/or photoallergy to sunscreening agents was diagnosed in 8 subjects (7.4%). Oxybenzone was positive in 4 patients, isoproyl dibenzoylmethane in 3 patients, p-aminobenzoic acid and 2-ethylhexyl-p-methoxycinnamate in 1 patient, respectively. CONCLUSION: Our results obtained during a 3-year period (January 1990 to June 1993) confirm that sunscreens are presently the commonest photoallergens.

Adolescent

[Etiopathogenesis of malignant melanoma of the skin. I. Clinico-biological and nosologic considerations].

Melanoma incidence is rapidly increasing in several countries. This neoplasm has been consistently studied in patients with dysplastic (pleomorphic) nevus, mainly in Anglo-Saxon populations. There is no evidence that among Italians the sequence pleomorphic nervus----cutaneous malignant melanoma shares the identical pathophysiologic mechanisms with the above mentioned form. Pleomorphic nevi are generally thought to be precursors of malignant melanoma of the skin, due to their chromosomal instability. Also common acquired nevi are lesions which can exhibit, although exceptionally, chromosomal abnormalities. Consequently, the sequence pleomorphic nevus----cutaneous malignant melanoma could also include the common nevus. The clinical implications of this stand-point, however, are to be more extensively investigated.

Humans

[Etiopathogenesis of malignant melanoma of the skin. II. Disease factors inherent in the organism].

Familial malignant melanoma with dysplastic (pleomorphic) nevus has been the most extensively investigated form of this neoplasm. Searches for dominant oncogenes and tumour recessive genes have been performed in various populations to clarify the pathogenesis of the disease. Some of the them have made in possible to localize the gene of the familial cutaneous melanoma with pleomorphic nevus on 1p chromosome. In various progression stages of this neoplasm different chromosomal abnormalities have been reported, which are only relatively specific of the disease stage. Growth substance (sex steroids, hormones, vitamins, immune factors, ions, prostaglandins, and others) regulate melanocyte proliferation and, perhaps, that of melanoma cells.

Growth Substances

[Etiopathogenesis of malignant melanoma of the skin. III. Disease factors inherent in the environment. Pathogenetic hypothesis].

Sunlight, particularly its UVB component, is thought to be the most important environmental factor for oncogenesis of melanoma. Its intensity, at the ground level, is a positive function of altitude and a negative function of latitude. Sun exposure and susceptibility in childhood seem to be major risk factors at least in Anglo-saxon countries. UV radiations are able to act as complete carcinogen. Eumelanin/pheomelanin ratio also appears as an important risk factor. Ionizing radiations, heat and traumas have been seldom related to melanoma carcinogenesis. Several chemicals, among them drugs and toxic drugs, add to the list of possible causative agents. Loss of alleles encoding for suppressor factors, caused by UV radiation, might play a significant role in carcinogenesis. A model is proposed, for "mediterranean" vs "caledonian" melanoma, in which the phenotypic sequence melanocytic nevus----melanoma would exhibit peculiar characteristics.

Humans

Simultaneous occurrence of lichen striatus in siblings.

Lichen striatus (LS) is a self-limiting linear papular dermatosis of unknown etiology seen mostly in children. We report LS occurring in two pairs of siblings: two sisters who had LS at an interval of 6 months and a brother and sister who had the dermatosis contemporaneously after an episode of flulike fever. In all four patients family history was positive for atopy. LS is frequently associated with atopic diseases. The abnormal immune status of patients with atopy may be a predisposing factor in the induction of LS. In our patients the simultaneous occurrence of LS in siblings after a flulike fever appears to corroborate the hypothesis that a viral infection is a possible candidate, as other authors have proposed. The rarity of familial cases of LS is, in our opinion, due to the exceptional confluence of difference sporadic events (atopy, viral infection caught at a specific period of life such as childhood, and a genetic predisposition) simultaneously present in the same patient.

Child