Histological and histochemical changes of the skin with aging

This study comprised skin biopsies from the upper back of 30 healthy males at different ages. They were divided into 3 groups of 10 males each, group I aged [20 - 40 years], group II aged [40 - 60 years] and group III aged over 60 years. The results of the present study showed marked histological and histochemical skin changes occurring with aging. The epidermis was reduced in thickness with flattening of the dermoepidermal junction with age. The thickeness of the epidermis was 67. 5 microm to 189 microm in the first group, 54 microm to 108 microm in the second group, 40. 5 microm to 81 microm in the third group. The basal cell layers of the epidermis showed areas of heterogenicity with variations in the shape, size and staining characters of their cells. The dermis of old subjects showed elastosis with more randomness in the arrangement of the elastic fibres. An overall decrease in the collagenous fibre content of the dermis was also demonstrated with aging. Both alkaline phosphatase and succinic dehydrogenase enzyme activity decreased with aging

Bencard skin test in chronic urticaria

Bencard pitch skin tests with different allergens were performed on 127 patients with chronic urticaria. 100 [78.7%] patients were reactive while 27 [21.3%] patients were non reactive. No significant correlation was found between prick skin test results and either the age or the sex of the patients. Highest percentages of positivity were found with inhalant allergens e.g. house dust [44/127 i.e. 34.6%]; house dust mite [30/127 i.e. 23.6%] and feathers [26/124 i.e. 20.4%]. Atopy however, does not seem to play an important role in chronic urticaria. Prick tests with food allergens showed positive reactions in 15.7% [20/127] of patients. Most of the patients with penicillin allergy were recommended to be on a diet free from milk and milk products. In 50% this was successful. The value of these findings is discussed. Desensitization was performed for 47 patients. 21 [44.7%] only reported improvement. The frequent recurrence and the life long treatment limit its value. Desensitization is thus recommended in the routine treatment of chronic urticaria