ARTHRITIS
Ankylosing Spondylitis (AS)
Ankylosing
spondylitis (AS) is a chronic inflammatory rheumatic disease that primarily
affects the axial skeleton, especially the sacroiliac joints and spine. It
belongs to a group of conditions known as spondyloarthritides and is
characterized by progressive inflammation that can lead to structural damage,
spinal stiffness, and reduced mobility.
What is it
Ankylosing
spondylitis is an immune-mediated inflammatory disorder in which chronic
inflammation occurs at the sites where ligaments and tendons attach to bone
(entheses), particularly in the spine and sacroiliac joints. Over time, this
inflammation can lead to new bone formation, resulting in fusion (ankylosis) of
spinal segments and loss of flexibility.
What causes it
The exact cause
of AS is not fully understood, but it is strongly associated with genetic
factors, especially the presence of the HLA-B27 gene, which is found
in most patients with AS. Environmental triggers, such as infections, may
activate the immune system in genetically predisposed individuals. The disease
involves abnormal immune responses that promote chronic inflammation and
pathological bone formation.
What are the
symptoms
Symptoms usually
begin in late adolescence or early adulthood. The most common symptom is
chronic inflammatory back pain, characterized by gradual onset,
improvement with exercise, worsening with rest, and night pain. Morning
stiffness lasting longer than 30 minutes is typical. Other symptoms include
reduced spinal mobility, buttock pain due to sacroiliitis, fatigue, and chest
wall stiffness leading to reduced lung expansion. Extra-articular
manifestations may include uveitis, enthesitis, peripheral arthritis,
inflammatory bowel disease, and, less commonly, cardiac involvement.
How the
diagnosis is made
Diagnosis is
based on a combination of clinical features, imaging, and laboratory
findings. Imaging of the sacroiliac joints is central to diagnosis. X-rays
may show sacroiliitis in established disease, while MRI can detect early
inflammatory changes before structural damage appears. Blood tests may show
elevated inflammatory markers (ESR, CRP), and testing for HLA-B27 supports the
diagnosis but is not diagnostic on its own. Classification criteria such as the
ASAS criteria are commonly used.
Importance of
diagnostic tests
Diagnostic tests
are crucial for confirming AS, detecting early disease, distinguishing it
from mechanical back pain, and assessing disease activity and progression.
MRI is particularly important for identifying early inflammation, allowing
diagnosis before irreversible structural changes occur.
Importance of
early diagnosis
Early diagnosis
is essential because structural damage and spinal fusion can be irreversible.
Identifying AS early allows prompt initiation of therapy, which can reduce
inflammation, improve symptoms, maintain spinal mobility, prevent deformity,
and enhance quality of life. Delayed diagnosis is associated with worse
functional outcomes.
Management
options
Management aims
to control inflammation, relieve pain, and preserve function. Non-steroidal
anti-inflammatory drugs (NSAIDs) are first-line treatment. Biologic
therapies, particularly tumor necrosis factor (TNF) inhibitors and
interleukin-17 inhibitors, are used in patients with active disease not
controlled by NSAIDs. Physiotherapy and regular exercise are essential
components of care. Posture training, smoking cessation, and patient education
are important supportive measures. Surgery may be considered in severe
deformity or advanced joint damage.
Prognosis
Ankylosing
spondylitis is a chronic, lifelong condition with variable progression.
With early diagnosis and modern therapies, many patients achieve good symptom
control and maintain functional independence. Without adequate treatment, AS
may lead to significant spinal rigidity, disability, and reduced quality of
life.
Gout
Gout is a common inflammatory arthritis caused by the deposition of monosodium urate crystals in joints and surrounding tissues due to elevated serum uric acid levels. It is characterized by sudden, severe episodes of joint pain and inflammation and can become chronic if inadequately treated.
What is it
Gout is a crystal-induced arthropathy resulting from hyperuricemia, a condition in which uric acid accumulates in the blood and forms crystals. These crystals deposit in joints, tendons, and soft tissues, triggering intense inflammatory responses. Gout most commonly affects the first metatarsophalangeal joint of the big toe but can involve other joints over time.
What causes it
Gout is caused by increased production or decreased excretion of uric acid. Risk factors include genetic predisposition, male sex, increasing age, obesity, excessive consumption of purine-rich foods (red meat, seafood), alcohol (especially beer), sugary beverages, and certain medications such as diuretics. Renal impairment and metabolic syndrome also increase the risk. When uric acid levels exceed its solubility, crystals form and precipitate in tissues.
What are the symptoms
Gout typically presents with acute attacks characterized by sudden onset of severe joint pain, swelling, redness, warmth, and tenderness. The affected joint is often extremely sensitive, and even light touch can be painful. Attacks frequently occur at night. Untreated gout may progress to chronic gout, with persistent joint inflammation, reduced mobility, and the formation of tophi—nodular deposits of urate crystals in soft tissues. Systemic symptoms such as fever and malaise may occur during acute attacks.
How the diagnosis is made
The gold standard for diagnosing gout is the identification of monosodium urate crystals in synovial fluid obtained by joint aspiration. These crystals appear needle-shaped and negatively birefringent under polarized light microscopy. Serum uric acid levels are supportive but may be normal during an acute attack. Imaging modalities such as ultrasound and dual-energy CT can detect urate crystal deposition and joint damage, especially in chronic disease.
Importance of diagnostic tests
Diagnostic tests are essential to confirm gout, distinguish it from septic arthritis or other inflammatory arthritides, and guide appropriate treatment. Crystal identification provides definitive diagnosis, while imaging helps assess disease burden, detect tophi, and monitor progression or response to therapy.
Importance of early diagnosis
Early diagnosis allows for prompt treatment of acute attacks and initiation of urate-lowering therapy, reducing the frequency and severity of flares. Early intervention prevents chronic joint damage, tophi formation, and renal complications such as kidney stones and urate nephropathy.
Management options
Management includes treatment of acute attacks and long-term urate control. Acute gout is treated with non-steroidal anti-inflammatory drugs (NSAIDs), colchicine, or corticosteroids. Long-term management focuses on lowering serum uric acid using medications such as allopurinol or febuxostat. Lifestyle modifications, including weight loss, dietary changes, reduced alcohol intake, and adequate hydration, are essential components of care.
Prognosis
Gout has an excellent prognosis when properly managed. With effective urate-lowering therapy and adherence to lifestyle modifications, most patients achieve long-term remission and prevention of joint damage. Without treatment, gout can become chronic, leading to disability, joint destruction, and systemic complications.
Osteoarthritis(OA)
Osteoarthritis (OA) is the most common form of arthritis and a leading cause of chronic joint pain and disability worldwide. It is a degenerative joint disease characterized by the gradual breakdown of articular cartilage, changes in the underlying bone, and inflammation of surrounding joint structures. OA most commonly affects weight-bearing joints such as the knees, hips, and spine, as well as the hands.
What is it
Osteoarthritis occurs when the protective cartilage that cushions the ends of bones within a joint wears down over time. As cartilage deteriorates, bones may rub against each other, leading to pain, stiffness, reduced mobility, and structural joint changes such as osteophyte (bone spur) formation.
What causes it
OA is caused by a combination of mechanical, biological, and genetic factors. Ageing is the strongest risk factor due to reduced cartilage repair capacity. Other causes include joint overuse, previous joint injury or surgery, obesity (which increases joint load and inflammation), muscle weakness, joint malalignment, and hereditary factors. Metabolic conditions and repetitive occupational or sports activities also contribute.
What are the symptoms
Symptoms develop gradually and worsen over time. Common features include joint pain that increases with activity and improves with rest, morning stiffness lasting less than 30 minutes, joint swelling, crepitus (a grinding sensation), reduced range of motion, and functional limitation. In advanced disease, pain may occur even at rest and joint deformity may develop.
How the diagnosis is made
Diagnosis is primarily clinical, based on patient history and physical examination. Imaging supports the diagnosis, with X-rays being the most commonly used tool, showing joint space narrowing, osteophytes, subchondral sclerosis, and cysts. MRI may be used to assess early cartilage changes or soft tissue involvement. Blood tests are typically normal and are used mainly to exclude inflammatory arthritis.
Importance of diagnostic tests
Diagnostic tests help confirm OA, determine disease severity, rule out other conditions, and guide management decisions. Imaging provides objective evidence of structural damage and helps monitor disease progression or response to treatment.
Importance of early diagnosis
Early diagnosis allows for timely intervention to slow disease progression, reduce pain, preserve joint function, and improve quality of life. Lifestyle modifications, weight management, and exercise are most effective when implemented early, potentially delaying the need for surgical intervention.
Management options
There is no cure for OA, but treatment focuses on symptom control and functional improvement. Non-pharmacological measures include patient education, weight loss, physiotherapy, strengthening exercises, and assistive devices. Pharmacological options include topical or oral analgesics and non-steroidal anti-inflammatory drugs (NSAIDs). Intra-articular injections (corticosteroids or hyaluronic acid) may provide temporary relief. Surgery, such as joint replacement, is considered in advanced cases.
Prognosis
Osteoarthritis is a chronic, progressive condition, but its course varies among individuals. With appropriate management, many patients maintain good function and quality of life. Early diagnosis and comprehensive treatment significantly improve long-term outcomes.
Psoriatic Arthritis(PsA)
Psoriatic arthritis (PsA) is a chronic inflammatory musculoskeletal disease associated with psoriasis. It affects both the skin and joints and is classified as a form of seronegative spondyloarthritis. PsA can cause joint damage, functional impairment, and reduced quality of life if not diagnosed and treated early.
What is it
Psoriatic arthritis is an immune-mediated inflammatory arthritis that occurs in individuals with psoriasis or a family history of psoriasis. It can affect peripheral joints, the spine, and entheses (sites where tendons and ligaments attach to bone). The disease shows diverse patterns, ranging from mild monoarthritis to severe, destructive polyarthritis.
What causes it
The exact cause of PsA is unknown, but it is thought to result from a combination of genetic predisposition, immune dysfunction, and environmental triggers. Genetic factors such as HLA-B27 and other HLA alleles increase susceptibility. Environmental factors, including infections, trauma (Koebner phenomenon), and stress, may trigger disease onset. These factors lead to immune activation and overproduction of inflammatory cytokines, including tumor necrosis factor (TNF) and interleukin-17.
What are the symptoms
Symptoms vary widely between individuals. Common features include joint pain, swelling, and stiffness, often worse in the morning. PsA may involve the distal interphalangeal joints, asymmetric oligoarthritis, or symmetric polyarthritis resembling rheumatoid arthritis. Dactylitis (sausage-like swelling of fingers or toes) and enthesitis (heel or tendon pain) are characteristic. Skin and nail changes such as psoriatic plaques, nail pitting, and onycholysis are common. Fatigue and back pain may occur, particularly with axial involvement.
How the diagnosis is made
Diagnosis is primarily clinical, supported by imaging and laboratory findings. There is no single diagnostic test for PsA. Blood tests are typically negative for rheumatoid factor, helping distinguish PsA from rheumatoid arthritis. Inflammatory markers (ESR, CRP) may be elevated. Imaging studies such as X-rays, ultrasound, or MRI can show joint erosions, new bone formation, enthesitis, and sacroiliitis. Classification criteria such as the CASPAR criteria are widely used.
Importance of diagnostic tests
Diagnostic tests are important for confirming PsA, excluding other inflammatory arthritides, assessing disease severity, and identifying structural damage. Imaging helps detect both inflammatory and destructive changes, guiding treatment decisions and monitoring disease progression.
Importance of early diagnosis
Early diagnosis is critical because joint damage can occur early and may be irreversible. Prompt recognition allows initiation of disease-modifying therapy to control inflammation, prevent joint destruction, reduce disability, and improve long-term outcomes. Delayed diagnosis is associated with worse functional status and quality of life.
Management options
Management of PsA requires a multidisciplinary approach. Treatment options include non-steroidal anti-inflammatory drugs (NSAIDs) for mild disease, conventional disease-modifying antirheumatic drugs (DMARDs) such as methotrexate, and biologic agents targeting TNF, IL-17, or IL-23 for moderate to severe disease. Targeted synthetic DMARDs may also be used. Non-pharmacological measures include physiotherapy, exercise, weight management, and skin-directed therapies for psoriasis.
Prognosis
Psoriatic arthritis is a chronic, progressive disease with variable severity. With early diagnosis and modern targeted therapies, many patients achieve good disease control and maintain function. Without appropriate treatment, PsA can lead to joint deformity, disability, and reduced quality of life.
Reactive Arthritis(ReA)
Reactive arthritis (ReA) is an inflammatory joint disease that develops as a reaction to an infection elsewhere in the body, most commonly in the gastrointestinal or genitourinary tract. It is classified under the spondyloarthritis group and typically affects young adults.
What is it
Reactive arthritis is an immune-mediated inflammatory arthritis that occurs after a bacterial infection, usually within 1–4 weeks of the initial illness. Although the triggering infection may have resolved, the immune system continues to generate inflammation, particularly in the joints, eyes, and genitourinary tract. The joints themselves are sterile, meaning no active infection is present.
What causes it
ReA is caused by an abnormal immune response following infection with certain bacteria, most commonly Chlamydia trachomatis, and gastrointestinal pathogens such as Salmonella, Shigella, Yersinia, and Campylobacter. Genetic susceptibility plays an important role, especially in individuals who are HLA-B27 positive, which is associated with more severe or prolonged disease. Environmental factors and immune dysregulation contribute to disease development.
What are the symptoms
Symptoms typically appear weeks after the initial infection. The hallmark feature is asymmetric inflammatory arthritis, usually affecting the lower limbs such as the knees, ankles, and feet. Joint pain, swelling, and stiffness are common. Extra-articular manifestations are characteristic and include conjunctivitis or uveitis, urethritis or cervicitis, mucocutaneous lesions, and enthesitis (especially heel pain). Some patients experience low back pain due to sacroiliac involvement, along with systemic symptoms such as fatigue and fever.
How the diagnosis is made
There is no single definitive test for reactive arthritis; diagnosis is primarily clinical, based on characteristic symptoms and a history of recent infection. Laboratory tests may show elevated inflammatory markers (ESR, CRP). Testing for HLA-B27 supports the diagnosis but is not essential. Microbiological tests, including urine or stool cultures and nucleic acid amplification tests, may help identify the triggering organism. Imaging such as ultrasound or MRI can detect joint inflammation and enthesitis.
Importance of diagnostic tests
Diagnostic tests are important to support the diagnosis, identify the triggering infection, exclude septic arthritis or other inflammatory joint diseases, and assess disease severity. Identifying the causative pathogen helps guide antibiotic therapy when appropriate and provides prognostic information.
Importance of early diagnosis
Early diagnosis allows for timely symptom control and treatment of any persistent infection, reducing the risk of chronic disease. Prompt management decreases pain, improves function, and lowers the likelihood of progression to chronic spondyloarthritis, which can lead to long-term disability.
Management options
Management focuses on symptom relief and control of inflammation. Non-steroidal anti-inflammatory drugs (NSAIDs) are first-line therapy. Corticosteroids may be used for severe joint or eye involvement, either locally or systemically. Antibiotics are indicated only if there is evidence of ongoing infection, particularly chlamydial infection. In patients with persistent or chronic disease, disease-modifying antirheumatic drugs (DMARDs) such as sulfasalazine or methotrexate may be used. Physiotherapy and exercise are important for maintaining joint function.
Prognosis
The prognosis of reactive arthritis is generally favorable, with most patients experiencing symptom resolution within 6–12 months. However, a subset of patients develop chronic or recurrent arthritis, especially those who are HLA-B27 positive. Early recognition and appropriate management improve long-term outcomes and quality of life.
Rheumatoid Arthritis(RA)
Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease that primarily affects the joints but can also involve multiple organs. It is characterized by persistent inflammation of the synovial lining of joints, leading to progressive joint damage, deformity, and functional disability if not adequately treated.
What is it
Rheumatoid arthritis is an inflammatory autoimmune disorder in which the immune system mistakenly attacks the synovium—the membrane lining the joints. This results in chronic inflammation, synovial hypertrophy, cartilage destruction, and bone erosion. RA typically affects joints symmetrically, especially the small joints of the hands and feet, and may also cause systemic manifestations.
What causes it
The exact cause of RA is unknown, but it results from an interaction between genetic predisposition and environmental triggers. Genetic factors, such as specific HLA-DRB1 alleles, increase susceptibility. Environmental factors include smoking, infections, and hormonal influences. These triggers activate an abnormal immune response, leading to the production of autoantibodies and inflammatory cytokines that sustain joint inflammation and damage.
What are the symptoms
Symptoms often develop gradually but may begin suddenly in some individuals. Common symptoms include joint pain, swelling, warmth, and stiffness, particularly morning stiffness lasting longer than one hour. RA typically affects joints symmetrically. Systemic symptoms such as fatigue, low-grade fever, weight loss, and malaise are common. As the disease progresses, joint deformities, reduced mobility, and extra-articular manifestations such as rheumatoid nodules, lung involvement, and cardiovascular complications may occur.
How the diagnosis is made
Diagnosis is based on a combination of clinical assessment, laboratory tests, and imaging. Blood tests may reveal elevated inflammatory markers (ESR and CRP), rheumatoid factor (RF), and anti-cyclic citrullinated peptide (anti-CCP) antibodies, which are highly specific for RA. Imaging studies such as X-rays, ultrasound, or MRI help identify joint inflammation and early erosive changes. Classification criteria from the American College of Rheumatology and the European League Against Rheumatism (ACR/EULAR) are commonly used.
Importance of diagnostic tests
Diagnostic tests are essential for confirming RA, differentiating it from other inflammatory arthritides, assessing disease activity, and predicting prognosis. Anti-CCP antibodies, in particular, are associated with more aggressive disease. Imaging helps detect early joint damage that may not be evident on physical examination.
Importance of early diagnosis
Early diagnosis is critical because RA causes irreversible joint damage early in the disease course. Initiating treatment during the “window of opportunity” significantly improves outcomes by reducing disease activity, preventing structural damage, preserving function, and decreasing long-term disability.
Management options
Management of RA aims to achieve disease remission or low disease activity. Treatment includes disease-modifying antirheumatic drugs (DMARDs) such as methotrexate, which are the cornerstone of therapy. Biologic agents and targeted synthetic DMARDs are used in moderate to severe cases. NSAIDs and corticosteroids help control symptoms but do not prevent disease progression. Non-pharmacological management includes physiotherapy, occupational therapy, patient education, and lifestyle modifications.
Prognosis
RA is a chronic, lifelong condition, but advances in early diagnosis and targeted therapy have significantly improved prognosis. Many patients achieve remission or sustained disease control. Without proper treatment, RA can lead to severe disability, reduced quality of life, and increased mortality due to systemic complications.
