Difficulty in early diagnosis of "psoriatic arthritis"?

*Only for medical professionals to read and refer to the latest research data and treatment principles, here are all! In line with the original intention of "spreading the strongest rheumatism and creating a new academic fashion", on the occasion of leaving the old and welcoming the new, the "medical world" media teamed up with nearly 20 well-known experts in the field of rheumatism from the four top rheumatology departments in China, covering 8 rheumatism In the field of hot diseases, we will start the "Rheumatism and the Waves-2020 Annual Rheumatism Inventory".

In this issue, Professor Deng Xuerong from Peking University First Hospital brings us an inventory of the annual progress of psoriatic arthritis (PsA).

One out of 100 people may suffer from PsA! PsA is a common disease in the Department of Rheumatology and Immunology.
The incidence of PsA in the general population in my country is 0.
1% to 1%.

Due to differences in genetic factors and classification criteria, the incidence of PsA varies significantly among different countries and regions (Figure 1).

7% to 48% of patients with psoriasis (PsO) will progress to PsA.

Figure 1 The global incidence of PsA There are currently many possibilities for the risk factors of PsO progressing to PsA, such as obesity, intestinal flora imbalance, infection, mechanical stress stimulation, etc.

List of important research results of PsA! PsA is considered to be a serologically negative inflammatory joint disease, which is a significant difference between it and rheumatoid arthritis.

Many scholars are committed to discovering more biomarkers of PsA to help clinicians make earlier diagnosis and identification.
Many results have been achieved so far: • An Italian study found that the serum and synovial fluid of PsA patients can be Detection of nuclear interferon-inducible protein (IFI) 16 and its antibodies, especially in cases with elevated C-reactive protein (CRP); • A Canadian study found that the level of CXCL10 in serum decreased and PsO progressed to PsA Related; PsA continues to decline after the onset; • A Danish study found that compared with healthy controls, the pre-arginine neo-epitope fragment (PROM) produced by matrix metalloproteinases in PsA patients increased; PROM is a new type of organism Markers can reflect connective tissue remodeling; • Another Canadian study found that osteopontin (OPN) is a potential biomarker of PsA; OPN is a cytokine that can increase interferon (IFN) γ and interleukin The production of (IL)-12 reduces the production of IL-10 and promotes the combination of osteoclasts and mineralized bone matrix.

In recent years, the imaging examination of PsA has also made great progress: first, ultrasound can be used for the early diagnosis of PsA; distinguish symptomatic or asymptomatic finger/plantaritis, the former is more manifested as tendon and paratendon structure involvement , The latter is often manifested as synovitis.

As for X-rays, the application of the simplified PsA radiology score (SPARS) needs more exploration.

New technologies include dual-energy CT (DECT), high-resolution peripheral CT (HRpQCT) and fluorescence optical imaging (OCT).

The Department of Rheumatology and Immunology, Peking University First Hospital, published a study at the European Alliance Against Rheumatism (EUALR) meeting in 2020, aiming to evaluate the role of ultrasound in the early diagnosis of PsA, and to further discover some valuable PsA diagnosis Ultrasound features.

A total of 66 patients with suspected PsA or early PsA (disease duration <2 years) in China and Britain were enrolled in the study.
Physical examination and ultrasound examination were performed at the same time. The results of the study are as follows: The specificity of the ultrasound-based classification criteria for psoriasis (CASPAR) is higher than that based on physical examination (96.
7% vs 53.
3%), but the sensitivity is slightly lower (91.
7% vs 97.
2%); 36 patients were finally diagnosed PsA, 30 cases were non-PsA patients; PsA patients had a higher skin quality of life index (DLQI) than non-PsA patients; PsA patients had more nail changes than non-PsA patients (69.
4% vs 26.
7%, P= 0.
001) and new bone formation (hand X-ray) (66.
7% vs 13.
3%, P<0.
001); compared with non-PsA patients, PsA patients had more synovitis/synovial hyperplasia (58.
3% vs 20.
0%, P=0.
002), tenosynovitis (38.
9% vs 3.
3%, P=0.
001) and enthesitis (52.
8% vs 13.
3%, P=0.
002); regression analysis showed that nail changes, X-ray new bone formation, ultrasound tenosynovitis and ultrasound Enthesitis is a risk factor predicting the diagnosis of PsA.

The study concluded that ultrasound can improve the specificity of CASPAR standards compared with physical examination; combined with nail changes, X-ray new bone formation, ultrasound tenosynovitis and ultrasound enthesitis can improve the early diagnosis of PsA.

In terms of X-ray, a SPARS related study was conducted abroad.

The study evaluated 30 hand joints including wrist joints and 10 foot joints (Figure 2).
The evaluation included bone erosion, joint space stenosis (JNS) and bone proliferation (BP), with a score of 0~ 120 points.

Figure 2 The joint parts evaluated by SPARS are in the existing scoring system.
For example, the modified Sharp score (mSvdHS) does not evaluate BP, while the PsA Ratingen scoring system (PARSS) does not evaluate JNS.

Therefore, the SPARS score is relatively more comprehensive.

The average scoring time obtained by the study is as follows: •SPARS: 4.
5 points • mSvdHS: 14.
4 points •PARSS: 10.
1 points It can be seen that SPARS takes the least time and is more conducive to the evaluation of structural damage in PsA patients. PsA patients are also prone to many comorbid diseases, such as metabolic syndrome, hypertension, uveitis, anxiety or depression, etc.
, as shown in Table 1: Table 1 PsA comorbidity related research, which reminds clinicians when treating PsA patients Need to pay close attention to its comorbidities.

Take a look at EULAR's latest treatment recommendations! At present, multiple therapeutic targets of PsA have been discovered, corresponding to a variety of new therapeutic drugs.

PsA's target treatment (T2T) has also evolved with the progress of research.
From EULAR in 2015, "Through regular monitoring or appropriate adjustment of treatment, remission or minimal disease activity (MDA) or low disease activity (LDA) can be achieved.
As an alternative target, it has been transformed into today’s “disease mitigation or LDA” (2019 EULAR).

How to treat PsA compliance treatment? • International treatment guidelines are mainly based on the successful use of T2T in rheumatoid arthritis, thereby approving the use of T2T in PsA to obtain remission or LDA; • In addition to clinical efficacy, cost, convenience, comorbidities, and complications (adverse reactions) And combined medication are also important issues that doctors and patients need to consider when determining treatment goals; • Due to the heterogeneity of the disease and the lack of a consistent definition of remission and LDA, it is more challenging to choose an appropriate PsA treatment.

In 2019, EULAR issued a new PsA drug treatment recommendation, which has been updated in the 2015 version of the treatment recommendation.
The general principles are as follows: • Psoriatic arthritis is a heterogeneous disease that can develop into severe disease.
Diseases may require multidisciplinary treatment; • Treatment should aim at providing the best medical care and must be based on joint decisions between patients and rheumatologists on efficacy, safety and cost; • Rheumatologists should be responsible Joints of patients with psoriatic arthritis; if the patient has serious skin diseases at the same time, they need to cooperate with a dermatologist; • The main goal of treatment is to maximize the quality of life by controlling symptoms and preventing structural damage and inflammation; • Each musculoskeletal manifestation should be considered, and corresponding treatment decisions should be made; • Skin, eye, and gastrointestinal symptoms and comorbidities, such as metabolic syndrome, cardiovascular disease, or depression, should be considered. There are 12 specific recommendations: Recommendation 1: Treatment is aimed at alleviating the condition, or through regular disease activity assessment and appropriate adjustments to the treatment plan to reduce disease activity; Recommendation 2: Non-steroidal anti-inflammatory drugs (NSAIDs) can be used for relief Musculoskeletal symptoms and signs; Recommendation 3: Local injection of corticosteroids can be used as an adjuvant treatment of PsA; Use systemic corticosteroids with caution, and it is recommended to use the lowest effective dose; Recommendation 4: In patients with polyarthritis, it should be promptly initiated Beginning with traditional synthetic anti-rheumatic drugs (csDMARDs), methotrexate (MTX) should be the first choice for patients with skin involvement; Recommendation 5: In patients with monoarthritis or oligoarthritis, especially with structural damage, erythrocyte sedimentation rate/CRP CsDMARDs should be considered for poor prognostic factors such as elevated, toe inflammation, or nail involvement; Recommendation 6: PsA patients with peripheral arthritis who have insufficient response to at least one csDMARDs should start treatment with biological DMARDs (bDMARDs); When there is related skin involvement, IL-17 inhibitors or IL-12/23 inhibitors can be the first choice; Recommendation 7: For PsA patients with peripheral arthritis, and insufficient response to at least one csDMARDs and at least one bDMARDs, or When bDMARDs are not applicable, JAK inhibitors can be considered; Recommendation 8: For patients with mild disease, at least one csDMARDs response is insufficient, and bDMARDs and JAK inhibitors are not applicable, PDE4 inhibitors can be considered; Recommendation 9: For In patients with confirmed enthesitis, if the response to NSAIDs or local injection of glucocorticoids is insufficient, bDMARDs should be considered; Recommendation 10: For patients with axial joint disease, if the response to NSAIDs is insufficient, bDMARDs should be considered.
According to current practice, tumor necrosis factor (TNF) inhibitors can be used; when related skin is involved, IL-17 inhibitors can be the first choice; Recommendation 11: For patients with insufficient response or intolerance to bDMARDs, consider switching to another Two kinds of bDMARDs or tsDMARDs, including conversion within one category; Recommendation 12: In patients with sustained remission, consider cautiously gradually reducing DMARDs.

Refer to Figure 3 and Figure 4 for the treatment process for different stages of the disease in this treatment recommendation.

  Figure 3 Update on EULAR PsA treatment recommendations in 2019: Phase I&II Figure 4 Update on EULAR PsA treatment recommendations in 2019: Summary of Phase III&IV PsA is a complex autoimmune disease with diverse manifestations and a higher incidence in PsO patients ; New biomarkers and imaging techniques can assist in the early diagnosis of PsA; the purpose of treatment should be to achieve remission or LDA through regular disease activity assessment and appropriate treatment adjustments; according to the patient’s clinical characteristics and immunological phenotype Individualized precision treatment; attention to comorbid diseases of PsA requires multidisciplinary treatment.

Expert profile Prof.
Xuerong Deng graduated from Peking University School of Medicine.
He is currently the chief physician of the Department of Rheumatology and Immunology of Peking University First Hospital, and the deputy leader of the imaging group of the Rheumatology and Immunology Physicians Branch of the Chinese Medical Doctor Association.
The main research direction of the member and secretary of the academic group is various arthritis diseases and musculoskeletal ultrasound.
EULAR-certified musculoskeletal ultrasound trainers have served as visiting scholars in the University of Hong Kong Queen Mary Hospital and the University of Leeds Rheumatology and Musculoskeletal Medicine Center.
Travel Scholar Award of the Japanese Society of Rheumatology