Textbook of Psoriasis Jayakar Thomas, Parimalam Kumar, Sindhu Ragavi Balaji, Dinesh Kumar Devaraj
INDEX
×
Chapter Notes

Save Clear


IntroductionCHAPTER 1

Psoriasis, a common skin disease which is probably as old as mankind is seen in any age group from the newborn. Psoriatic skin changes have been described since biblical times. The first documented description is found in the Old Testament in the third book of Moses. It was confused with leprosy for hundreds of years, and, therefore, many people with psoriasis were ostracized in the middle age (Fig. 1.1). At the beginning of the 19th century, Robert Willan, an English physician, was the first to clinically describe psoriasis (Crissey and Parish 1998). Humankind suffered and studied this disease for at least 3,000 years, and, naturally, several possible causes for the disease have been hypothesized.1
Psoriasis is now classified as an immune-mediated inflammatory disease of the skin. Psoriasis, a T-cell mediated chronic inflammatory disorder of the skin is seen in about 3.5% of the population.2 One-third of psoriasis cases in a dermatology center are seen in pediatric age group.3 It is recognized as the most prevalent autoimmune disease caused by inappropriate activation of the cellular immune system and affects people of all age including the newborn. Psoriasis is a lifelong inflammatory disorder of the skin that can vary widely in its presentation, but is characterized by the common features of erythema, thickening, and scaling of the skin. The diagnosis is usually made on clinical grounds by any well trained clinician.
zoom view
Fig. 1.1: History of psoriasis since 400 BC
2Despite considerable research into its etiology, there are still no definitive genetic or biochemical markers for psoriasis, and it continues to be diagnosed primarily based on skin manifestations. Its impact on a patient depends not only on the percentage of body surface area of the lesions but also on their location. Involvement of the hands, feet, scalp, and genital areas can have a disproportionate effect on quality of life and disability. Additionally, in a significant subset of psoriasis patients, the disease process involves progressive damage to the articular joints. Up to 30% of people with psoriasis also develop psoriatic arthritis (PsA) which may be over diagnosed or under diagnosed due to the heterogeneity of its expression.
Patients with arthropathy or enthesopathy of various types may be over diagnosed as PsA in the presence of cutaneous psoriasis and the diagnosis PsA may be missed, in the absence of cutaneous psoriasis. Patients with PsA are at increased risk for developing other comorbidities. Moreover, clinical studies have increasingly revealed associations of psoriasis and its treatments with many systemic diseases. Although establishing causality in these associations remains problematic, these associations have immediate diagnostic and therapeutic implications.
The trend of increasing incidence of childhood psoriasis, observed in recent times is alarming. The chance of translating this into an increase in morbidity due to psoriasis during adulthood cannot be ruled out.
Psoriasis not only affects physical well-being but has emotional and relational consequences that go far beyond the skin. Timely diagnosis and appropriate management can not only arrest progression but also minimize the psychosocial burden imposed by this illness. Thereby disfiguring states and its evolution into a metabolic syndrome requiring extensive treatment can well be averted.
Every physician treating a psoriatic patient, must look past the skin and see the patient as a whole, with particular attention to address the associated comorbid conditions. Although there is no consensus regarding screening for metabolic conditions in psoriatic patients, it is strongly recommended that all adult patients above the age of 40 are screened for metabolic comorbidities more so with reference to female patients and those with positive family history of psoriasis or comorbidity.
The role of biomarkers for assessment of disease severity, for prediction of the outcome of therapeutic interventions, and for distinction between the different clinical variants of the disease has been emphasized.4 Therapeutic options are approached from different angles and an attempt has been made to cover as much recent drugs as possible including the role of monoclonal antibodies targeting interleukin-17 receptor A (IL-17RA) and IL-17A in the treatment of plaque psoriasis.5 A fair understanding of the disease's underlying inflammatory processes may well improve the management of patients with psoriasis. It is suggested that a holistic approach, including education, counseling and psychological support, regular follow-up is needed for optimal care of psoriatic patients.
This book will cover almost all aspects of psoriasis with particular attention to pediatric psoriasis, including the rare clinical form like congenital erythrodermic psoriasis and present the latest update especially on the etiopathogenesis and treatment options. An evidence based approach has been given while discussing these issues. There is increasing awareness the world over that psoriasis is more than “skin deep” and is now emerging as a systemic disease. 3It is attempted to emphasize the role of inflammation as a major factor, leading to multiple organ dysfunction. Similarly, the concept, “psoriatic march” is also thrashed out though it is not yet formally proven. Finally, the reader will accept that a holistic approach, including education, aggressive treatment wherever necessary along with psychological support in the form of empathy rather than sympathy, is all that is needed for care of psoriatic patients. The main aim of the treatment should be to reduce the burden of the disease over time by controlling symptoms, helping the patient to cope with the chronic nature of the disease, limiting psychological and relational consequences, and preventing systemic complications and comorbidity by choosing the right drug at the right moment and keeping a strict vigil on the side effects.
REFERENCES
  1. Coimbra S, Oliveira H, Figueiredo A, Rocha-Pereira P, Santos-Silva A. Psoriasis: epidemiology, clinical and histological features, triggering factors, assessment of severity and psychosocial aspects. Psoriasis-A Systemic Disease. Editor: Jose O’Daly; INTECH, Open Access Publisher, 2012. Available at (http://www.intechopen.com/books/psoriasis-a-asytemic-disease).
  1. Kurd SK, Gelfand JM. The prevalence of previously diagnosed and undiagnosed psoriasis in US adults: results from NHANES 2003-2004. J Am Acad Dermatol. 2009;60:218–24.
  1. Raychaudhuri SP, Gross J. A comparative study of pediatric onset psoriasis with adult onset psoriasis. Pediatr Dermatol. 2000;17:174–8.
  1. Molteni S, Reali E. Biomarkers in the pathogenesis, diagnosis, and treatment of psoriasis. Psoriasis: Targets and Therapy. 2012;2:55–66.
  1. Gooderham M, Posso-De Los Rios CJ, Rubio-Gomez GA, Papp K. Interleukin-17 (IL-17) inhibitors in the treatment of plaque psoriasis: a review. Skin Therapy Lett. 2015;20(1):1–5.