Background According to ACR data 15–20% patients (PTN) with psoriasis are developed with psoriatic arthritis (PsA). Herewith the enthesitis (ETS) as usual is the first signs of PsA manifestations. It is usually asymptomatic at the beginning of the disease, however it is successfully diagnosed with Doppler ultrasound (DU). In average, it takes about 2 years from beginning of the disease till diagnosis PsA is established. PsA treatment is low effective with DMARD, and middle effective with biologic therapy. Wherein no treatment restores the articular changes that have occurred. Thus the actual is to find some resolution to the effective therapy for PTN with psoriasis and also to identify the factors preceding the development of the PsA.

Objectives Consider the application of biologic therapy before the articular changes in PTN with psoriasis and predictors of psoriatic arthritis.

Methods Observed 82 PTN with pustural psoriasis without clinical manifestations of PsA. A physical examination (including PASI), a series of laboratory tests (hematology, CRP, RF, anti -ccp, HLA-B27, uric acid), DU to identify the PsA, its activity, as well as to the exclusion of other types of arthritis were used.

Results 3,7% PTN were diagnosed with PsA with articular changes. 23,1% PTN were founded with enthesitis. The remaining 73,2% PTN had no signs of enthesitis during physical examination and DU. PTN with enthesitis were divided into 2 groups. I – 47% PTN (22% of them had clinical manifestations of enthesitis; the average group PASI– 42,4±8,2) received a 52-weeks course of ustekinumab (45 mg administered subcutaneously initially and 4 weeks later, followed by 45 mg administered subcutaneously every 12 weeks). II group – 53% people (20% PTN had clinical manifestations of enthesitis; the average group PASI– 43,6±9,0) did not receive biological therapy, but only standart treatment for psoriasis. After 1 year follow-up after completion of the treatment course – 11% PTN from group I developed PsA with articular changes. From the group II in 80% PTN developed PsA with articular changes. The average group I PASI– 7,6±1,5; the average group PASI– 6,2±1,3. (p <0,05)

Conclusions Thus, the ustekinumab use in psoriatic PTN with enthesitis possibly may be reasonable and will hinder the development of PsA. Ustekinumab is also high effective for the improving of the psoriasis skin symptoms.

DU is the high effective diagnostic method for detecting enthesitis without clinical manifestations.

Frequency of screening DU in PTN with psoriasis, for the early detection of enthesitis is the perspective for further study.

Disclosure of Interest None declared