Systemic Lupus Erythematosus: A Systematic Approach to Arthritis of Rheumatic Diseases: Volume 4

By Syuichi Koarada

Systemic lupus erythematosus (SLE) is an autoimmune disease. SLE affects many parts of the body, with joint pain in the knees and hands being commonly reported symptoms. Arthritis is, therefore, one of the most common symptoms of the disease.

This book comprehensively summarizes information about SLE for medical professionals and students. The volume illustrates the process of making accurate diagnoses through systematic interpretation of ABCDEGFGI parameters: A (Alignment): malalignment and deformation; B (Bone): bone changes; C (Capsular lesions): cartilage and intra-articular lesions; D (Distribution): four dimensional distributions; E (Extra-bone): extra-articular soft tissue; F (Further information): further additional medical information; G (Goal): general analysis and integrated comprehensive diagnosis; H (Heal and Heath): treatment and prognosis; and I (Immunological analysis): immunological interpretations.

Key Features:

- Presents information about the clinical features of SLE and differential diagnosis through 11 chapters

- Covers both rheumatic symptoms and systemic symptoms

- Provides a comprehensive approach to SLE diagnosis and management which blends both rheumatology and radiology

- Explains the ABCDEFGI system for diagnosing and treating SLE patients

- Includes more than 750 detailed figures illustrating important information

- Includes references for further reading

The book is an informative resource for a wide range of scholarly and professional readers who may encounter SLE patients in clinical settings: rheumatologists, orthopedists, radiologists, physiatrists, immunologists, pediatricians, general physicians, medical technicians, caregivers and specialists in internal medicine.

• Language: English
• Publisher: Bentham Science Publishers
• Release date: Feb 11, 2022
• ISBN: 9789815050653

Book preview

Introduction of Diagnostic Approach for Systemic Lupus Erythematosus

Syuichi Koarada¹, ², ³, *, Yoshifumi Tada ³

¹ Department of Medical Technology and Sciences, International University of Health and Welfare, Okawa, Japan

² Division of Rheumatology, Takagi Hospital, Okawa, Japan

³ Division of Rheumatology, Faculty of Medicine, Saga University, Saga, Japan

Abstract

Musculoskeletal symptoms occur in up to 90% of systemic lupus erythematosus (SLE) patients. Lesions extend not only to joints but to the whole body, causing inflammation in diverse organs such as the skin, kidneys, lungs, nervous system, serous membranes and virtually across all organs of the body. The ABCDEFGHI method consists of A (Alignment): malalignment and deformation; B (Bone): bone changes; C (Capsular lesions): cartilage and intra-articular lesions; D (Distribution): four dimensional distributions: 1 intra-articular, 2 Intra region, 3 intra-body, 4 timeline; E (Extra-bone): extra-articular soft tissue; F (Further information): further additional medical information; G (Goal): general analysis and integrated, a comprehensive diagnosis from the information; H (Heal and Heath): treatment and prognosis; and I (Immunological analyzes): immunological interpretation (cytokines and phenotypes of immune cells). This chapter outlines a methodology for diagnosing the musculoskeletal and systemic manifestations of SLE.

Keywords: Musculoskeletal symptoms, Systemic lupus erythematosus (SLE), Systemic manifestations.

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* Corresponding author Syuichi Korada: Department of Medical Technology and Sciences, International University of Health and Welfare, Okawa, Japan; Email: [e-mail]

1. INTRODUCTION

Systemic lupus erythematosus (SLE) is a complex and clinically heterogeneous autoimmune disease. Musculoskeletal symptoms occur in up to 90% of SLE patients [1, 2]. Musculoskeletal disorders cause disabling symptoms in 70% of patients [3].

Despite being one of the most common symptoms, medical and basic researchers do not always pay the utmost attention to musculoskeletal symptoms. Joint symptoms may be neglected in SLE because systemic, cutaneous, and organ lesions are more prominent.

Both directly and indirectly, musculoskeletal symptoms affect patient quality of life (QOL), causing immobility and frailty. Ultimately, the musculoskeletal symptoms have a significant effect on the prognosis of the musculoskeletal system due to osteoporosis, compression fractures, necrosis of the femoral heads, and are irreversible.

Suppose patients with SLE are not diagnosed early. In that case, treatment may be delayed, the lesions and disorders will persist, and delayed diagnosis is often the cause of impaired patient quality of life.

Patients with rheumatoid arthritis always have joint radiography performed at the first visit and on regular examinations thereafter. On the other hand, in SLE patients, even if they have joint symptoms/deformities, radiography of the joints may not always be taken. It is the patient's desire to relieve the pain without using glucocorticoids in the treatment with more attention to lupus arthritis and musculoskeletal symptoms. SLE is a systemic disease, but it is important to recognize that SLE is also a joint disease.

Musculoskeletal involvement is one of the most common manifestations of SLE and is present in 69-95% of lupus patients [4-9]. Moreover, joint symptoms are frequently one of the earliest manifestations. Many patients with SLE can develop non-erosive arthritis. Joint lesions range from mild to severe, but clinically and historically, joint symptoms of SLE, including joint pain or arthritis, have usually been considered transient, mild, or moderate [10].

Arthritis in SLE is very important symptomatology, as 58% of patients have active musculoskeletal lesions even at relapse in one cohort study [10]. Historically, in 1872, Kaposi identified SLE arthritis and reported that joint lesions were a precursor to the more severe symptoms of lupus.

However, most researchers did not adequately study arthritis in SLE as a milder symptom compared to systemic symptoms. Even now, in daily practice, joint symptoms in SLE may be milder. Furthermore, it has been reported that arthralgia is one of the most influential symptoms on the quality of daily life from the perspective of the patient [11, 12]. Because it has been shown that joint involvement deeply impacts on quality of life in SLE patients [11]. Recently, many studies have shown that joint deformities also occur in SLE patients,causing erosive arthritis, the so-called rhupus syndrome, in up to 15% and Jaccoud’s arthropathy [10, 13-16]. Musculoskeletal ultrasonography and magnetic resonance imaging (MRI) have become useful tools in assessing patients with arthritis.

Surprisingly, these new imaging techniques have shown articular involvement of SLE in an unexpected higher prevalence [12]. The evaluation of various forms of lupus arthropathy with clinical and laboratory functions and images, including conventional radiography, musculoskeletal ultrasound, MRI, and other modalities, is described. In addition, images of musculoskeletal lesions are used to determine overlap with other diseases, rheumatoid arthritis (RA), spondyloarthritis, vasculitis syndrome, fractures, septic arthritis, and osteomyelitis. To diagnose lupus arthropathy, it is necessary to perform and interpret typical conventional and other diagnostic imaging.

The cause of the disease is still unknown. Genetic, hormonal, and environmental factors are thought to play important roles in the pathophysiology of SLE. Multiple genes show genetic susceptibility to SLE. Environmental factors such as ultraviolet (UV) light, viral infections, female gender, and exposure to estrogen-containing drugs induce SLE.

This book will serve as a useful reference in clinical and radiological diagnosis.

2. CLASSIFICATION OF LUPUS ARTHROPATHY

Arthropathy of SLE is clinically extremely diverse. There are two indicating categories: 1) non-erosive or erosive, and 2) non-deformable or deformable. However, it is clinically useful to divide into three categories: non-specific arthritis, non-erosive arthropathy (Jaccoud’s arthritis), and erosive arthritis (rhupus) [17]. Moreover, lupus arthropathy is clinically highly diverse and can be divided into at least six clinical forms.

Musculoskeletal abnormalities in SLE patients have tremendous clinical variability and include myositis, fasciitis, symmetric arthritis, non-erosive degenerative arthritis, spontaneous tendon rupture, soft tissue calcification, osteomyelitis, septic arthritis, terminal phalangeal sclerosis, erosion, and osteonecrosis (Table 1).

Table 1 Musculoskeletal Manifestations of Systemic Lupus Erythematosus.

2.1. Frequency of Arthritis Subtypes

Most patients with SLE have non-erosive and non-deforming arthritis. Patients with non-erosive arthritis are the most common (up to 35% of patients with SLE) [18]. Jaccoud’s arthritis (JA) is present in 10-35% of patients with SLE and is characterized by reducible, non-erosive deformities. Erosive arthropathy is not the usual pattern of arthritis in SLE and is found only in 5-10% of patients [18-21].

2.2. Arthritis Subtypes

2.2.1. Non-erosive Arthritis

Patients with non-erosive arthritis fall into two subgroups: non-deforming arthritis and deforming arthritis [18]. Moreover, patients with non-erosive deforming arthritis are classified as mild or severely deformed arthropathy (Jaccoud’s arthropathy).

Thus, ultimately, non-erosive arthritis is divided into three subtypes, non-deforming non-erosive non-specific arthritis (NDNE lupus arthritis), mild deforming non-erosive arthritis, and severe deforming non-erosive arthritis (Jaccoud’s arthritis) (Fig. 1) [18].

The first subtype of deforming non-erosive arthritis in SLE is Jaccoud’s arthritis. The subtype of Jaccoud’s arthritis follows a chronic course with severely deforming arthritis. However, joint lesions without erosions are reducible. Jaccoud’s arthritis affects the digits (ulnar deviation, swan-neck deformities), including the thumbs (Z deformity of the thumb), the wrists, and the knees predominantly.

Fig. (1))

Diagram of lupus arthritis. Subtype classification based on two indicators: erosive and erosive, deformable, and non-deformable.

The second subtype of non-erosive arthritis is lesions with mild deformity, synovitis of the digits, swan-neck deformities, ulnar deviation (digits), and dysfunction of the hands.

The last group is very mild arthritis without erosions and deformities. Patients with this subtype of lupus arthritis suffer from intermittent asymmetric polyarthritis characterized by swelling of soft tissues and tenderness of the joints.

2.2.2. Erosive Arthritis

In the group of erosive arthritis, a first subtype is an erosive form with deforming (from mild to severe) arthropathy with RA (erosive and deforming arthritis; rhupus) (Fig. 2). Patients with rhupus have erosive changes on radiography, most commonly in the hands [22, 23]. Although the definition of rhupus is controversial, rhupus is not in the clinical category of joint lesions found in SLE only and is generally considered a true overlap between SLE and RA [23, 24]. Patients with rhupus have a higher incidence of synovial proliferative changes, bone erosions, rheumatoid factor (RF) and anti-CCP positivity compared to patients affected by Jaccoud’s arthropathy and NDNE lupus arthritis. However, on the other hand, some researchers consider rhupus to be a variant of SLE arthropathy [25]. Rhupus, which is in the category of erosive arthritis, is practically difficult to distinguish from RA. Some patients with SLE may develop rhupus in association with circulating anti-CCP antibodies and alleles of MHC class II molecules, including HLA-DRB1 and HLA-DQB1 [26, 27].

Joint space narrowing and rheumatoid arthritis-like erosive joints are found in the intercarpal and radiocarpal joints. Mild erosive changes are also present in the MCP joints.

Finally, another subtype of erosive arthritis is non-specific erosive arthritis without deformity and/or RA. The possibility of early rheumatoid arthritis before deformation cannot be excluded. In addition, there is a true RA subtype, which only independently overlaps the systemic symptoms of SLE (overlap RA without lupus arthritis). More broadly, it should be considered that there may be complications of diseases other than SLE and rheumatoid arthritis; osteoarthritis, Sjogren's syndrome, other rheumatic diseases, viral infections, and fungal infections.

2.3. Osteonecrosis, Avascular Osteonecrosis (AVN)

Avascular osteonecrosis (AVN), also known as osteonecrosis, aseptic necrosis, and ischemic bone, was first reported to occur in SLE by Dubois and Cozen in 1960 [28]. Osteonecrosis was associated with the institution of corticosteroid therapy in the 1950s and was suspected of contributing to its etiology [28]. Imaging findings are like osteonecrosis caused by other etiology.

Osteonecrosis occurs in approximately 13% of SLE patients [29]. Osteonecrosis is most likely to affect the femoral head, humeral head, tibial plateau, and scaphoid [29]. The greatest risk factor for osteonecrosis in SLE is the use of 20 mg or more of prednisolone daily [30]. Other risk factors for osteonecrosis in SLE are Raynaud's phenomenon, vasculitis, and fat embolism.

Osteonecrosis is assessed by imaging studies, including plain radiography, bone scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI).

Especially, plain radiographs have been used for screening, diagnosis and evaluation of osteonecrosis [31]. These radiographs should be performed for the screening of osteonecrosis of the hip in lupus patients [31]. Femoral head necrosis is assessed for femoral head morphology and quality in anterior-posterior (AP) and frog-leg views. MRI can detect osteonecrosis at an early stage.

2.4. Osteoporosis

Patients with SLE treated with long-term, high-dose corticosteroids are at risk for osteoporosis [32].

2.5. Insufficient Fractures

In SLE, insufficiency fractures are likely to occur in bones weakened by normal or abnormal force, and the distribution of the sites is like that in rheumatoid arthritis [32].

3. APPROACHES TO DIAGNOSIS OF SLE

Clinical and radiological features of arthritis in SLE include swelling of soft tissue, periarticular osteoporosis, subluxations, and dislocations (subluxation of metacarpophalangeal joint [33-36], scapholunate dissociation, Jaccoud’s arthropathy), lack of erosion, absence of joint space narrowing, calcification, tendonitis, tenosynovitis, bursitis, and enthesopathy. However, sometimes, joint space narrowing and cystic bone changes occur. Rarely, there are also erosions on the second and third MCP joints in patients with rhupus. The distribution of arthritis is symmetrical, such as the hands, wrists, knees, and shoulders [37-39].

Diagnosis of SLE should be performed comprehensively and systematically as