THE FREQUENCY OF PSORIATIC ARTHRITIS IN PSORIATIC PATIENTS IN SULAIMANIA CITY

Objectives: To find out the frequency of psoriatic arthritis (PsA) in psoriatic patients in Sulaimania city, and to determine the clinical varieties of psoriatic arthritis in psoriatic patients. Patients and Methods: A sample of 132 patients with psoriasis attending the dermatology consultation clinic of Sulaimania city from January to July 2008 was included in the study. Patients were evaluated for evidence of arthropathy. All patients were interviewed by using a questionnaire form which was constructed according to CASPAR classification criteria. Arthritic patients were investigated by relevant laboratory tests and radiology (X-ray). Results: Out of 132 psoriatic patients, 34 cases fulfilled the CASPAR classification criteria for diagnosis of psoriatic arthritis which represents 25.8% of the sample. There was a female predominance (67.6%). Oligoarthritis was the commonest type of psoriatic arthritis, occurred in 29.4%, while isolated involvements of distal interphalangel joints (DIP) and axial skeletal were the least common. Enthesopathy was diagnosed in 58.8%, psoriatic nail lesions were observed in 32.4%, and 73.5% of psoriatic arthritis had extensive skin lesion which express the important relation of joint disease with the extent of skin lesion. Most of the polyarthritis and arthritis mutilans occurred in the age group 50-59, this relation between the severity of joint disease and advancing age was statistically significant. Conclusion: Nearly one-quarter of psoriatic patients had psoriatic arthritis, females were more affected, and the commonest type of arthritis recorded was oligoarticular type. INTRODUCTION soriatic arthritis is a chronic inflammatory arthritis associated with psoriasis. [1] P so r i a s i s is a common, chronic, and recurrent inflammatory disease of the skin characterized by circumscribed, erythematous, dry, scaling plaques of various sizes, the lesions are usually covered by silvery white lamellar scales. [2] It occurs often on the extensor surfaces, but may also affect the scalp and flexural areas as well as palms and soles. [1] It commonly affects nails with either pits and onycholysis. [1] It is widely varied throughout the world. This variation may be related to the fact that there are no valid criteria for the disease and various studies have used different case definitions. [1] According to the recent reports it has varied from 6% to 30% in some studies, [1] and has varied from 6 to 42% in other studies. [3] Both psoriasis and psoriatic arthritis affect men and women equally. A small minority of patients have synchronus onset of skin and joint features or have arthritis but never develop skin lesions. [4] In Caucasian population psoriasis is estimated to have a prevalence of 1 to 3%. Psoriasis and psoriatic arthritis are less common in other races in the absence of HIV infection. [5] Several sets of classification criteria for psoriatic arthritis has been proposed. The CASPAR (classification of psoriatic arthritis) group, an international group gathered to develop classification criteria for psoriatic arthritis. It proposed a new set of criteria for classification of psoriatic arthritis which was 99% specific and 92% sensitive for psoriatic arthritis. [1] (Table-l). Wright and Moll described the clinical patterns of psoriatic arthritis. These include: predominantly DIP joint disease, identified in 5%, arthritis mutilans, a very destructive form of arthritis, identified in about 5% of patients, oligoarthritis, affecting 4 or fewer joints often in an asymmetric distribution observed in 70% of the patients, polyarthritis, indistinguishable from rheumatoid arthritis, detected in 15% of patients and spondylarthritis which occur alone in about 5% of the patients. [1] These patterns may be helpful at the disease onset but they don't stay stable overtime, changing from one pattern to another is not uncommon. [1,6] Recently, other rheumatic manifestations of psoriasis, such as enthesopathy, osteoperiostitis, and other periarticular conditions, were recognized. [7] Patients with PsA demonstrate disease P MJBU, Vol 29, No. 1&2, 2011_____________________________________________________________________________ 58 progression over time, with more patients developing polyarthritis and increase in joint damage both clinically and radio logically. [1] Indicators of poor prognosis include younger age at onset, extensive skin involvement, polyarticular synovitis, HIV infection, high ESR at presentation, and association with HLAB27, B39 and DLW3. [8] PATIENTS AND METHODS This study is cross sectional study involving 132 patients with psoriasis. The patients were attending the dermatology clinic in Shaheed Saifaldeen polyclinic in Sulaimania city, over 6 months period from January to July 2008. The cases were diagnosed by a consultant dermatologist. All psoriatic patients were interviewed using a special questionnaire form, which was constructed according to the classification criteria (The CASPAR). The main part of the questionnaire form concerned with rheumatic complain of the patients, including the site, duration, the onset of complain whether started before, after, or with skin lesion, concomitantly examination was done. For each patient with rheumatic complain, laboratory tests (ESR, CRP, RF) and conventional radiography, were conducted. Patients with rheumatic complain were also sent for x-ray of back (spine and sacroiliac joints), hands (DIPJ) and sites of enthesis (e.g. insertion of plantar fascia to calcaneum) especially those who were complaining for a long time. However, this was not done or all patients because of the limited facilities. The severity and extent of psoriatic skin lesion was determined by using (the role of nine) with the help of a dermatologist. A skin lesion less than 7% of body surface area was regarded as mild, between 7 to 20% was classified as moderate, and a lesion more than 20% of the body surface area was regarded as extensive. [9] The patients were also checked for evidence of psoriatic nail lesions. Extraarticular manifestations of PsA were not included in the study. RESULTS The study enrolled 132 cases of psoriasis patients, 63 males and 69 females. The ages ranged from 1 to 86 years and the mean age was 43.29 years. All the patients were receiving treatment for psoriasis. Seventy eight patients (59.1%) had rheumatic complaints. Psoriatic arthritis was diagnosed in 34 patients, represented 25.8% of the studied sample (Table-1). The arthropathic patients were 11 males and 23 females, with a female to male ratio 2.1:1. The association between psoriatic arthritis and patient's gender was statistically significant, P-value (<0.05). The mean age for both males and females with PsA was 43±ll, their ages ranged from 22 to 63 years. The peak frequency of PsA was in the 5 th decade followed by the 6th and 4 th decades. (Table-2). Table 1. Prevalence of psoriatic arthritis according to sex. PSA Male Female Total