1Hanan A. Salem, 1Shaymaa El-Mongy, 2Samia Nassar, 3Mohamed El-Khatib, 4Eman El-Nashar, 5Azza Abd El-Baky and 5Elham R. Abd EL-Sameea
Departments of: Dermatology and Venereology, 1Al-Mansoura Faculty of Medicine and 2Tanta Faculty of Medicine, Departments of: 3Neurology and 5Clinical Pathology, Al-Mansoura Faculty of Medicine and Department of 4Histology and Cytology, Benha Faculty of Medicine, Egypt.
Emotional stress is one of the most powerful precipitating
factor in psoriasis. However, the pathomechanism whereby psychological factors
precipitate the disease are totally unknown. Research is now underway to
examine the interaction between the endocrine, nervous, and immune systems. The
aim of the study was to assess the function of sympathetic nervous system, to
detect the density of nerve fibres in lesional skin and to determine the number
of NK cells in the peripheral blood of patients with psoriasis. Twenty psoriasis
patients and 10 normal healthy control subjects were included in the study. For
each subject, plasma noradrenaline was determined by ELISA, and serum dopamine b
hydroxylase by Sympath TM25 enzymatic assay. The sympathetic skin response
(SSR) was examined. The density of skin nerve fibres was evaluated by detection
of neurofilaments immunohistochemically. Assessment of natural killer (NK)
cells in the peripheral blood was done by using specific monoclonal antibodies
to CD16 and measured by flow cytometry. There was significant increase in
plasma noradrenaline, serum dopamine b hydroxylase, NK (CD16) cells in peripheral blood in
patients than in control. Moreover, there was an increase in nerve fibres at
the dermo-epidermal junction and in the papillary dermis, in lesional psoriatic
skin than in control normal skin. However, there was no significant changes in
the values of latency or the amplitude of SSR in patients than in control. We
concluded that the sympathetic nervous system might have a particular role in
the pathogenesis of psoriasis possibly via enhanced sympathetic activity which
may lead to immune changes.