Inflammatory Seronegative Arthritides: Ankylosing Spondylitis, Psoriatic Arthritis, Reactive Arthritis, Polymyalgia Rheumatica

Question 1

Polymyalgia rheumatica
-presentation
-investigations
-management

Answer 1

Older adults

Rapid onset
Aching, morning stiffness in proximal limbs
NO WEAKNESS, related to high pain
Pain in multiple joints
Constitutional - fatigue, fever, night sweats, weight loss

High ESR
Normal CK

Pred => dramatic response

Question 2

Ankylosing spondylitis
-risk factors
-presentation
-diagnosis
-management

Answer 2

Male 20-30s
HLA B27

Lower back pain, stiffness with insidious onset
Worst in morning, improves with use
Reduced lateral and forward flexion
Anterior uveitis

Imaging is key
-sacroilitis, subchondral erosion, sclerosis, square lumbar vertebrae
-syndesmophytes (early)
-bamboo spine (late)
-apical fibrosis CXR, achilles tendonitis, anterior uveitis

NSAIDs + physio
-DMARDS only useful if peripheral joint involvement
Anti-TNF if no response with 2NSAIDS + 2episodes of active disease 3months apart
-etanercept, infliximab

Question 3

Psoriatic arthritis
-relationship with psoriasis
-risk factors
-presentation (patterns and signs)
-investigations

Answer 3

Chronic inflammatory erosive arthropathy, often precedes rash

Equal gender ratio - 50-60s
Genetic - HLA B27, B29
Environmental - joint, tendon trauma

Patterns
-Symmetrical/asymmetrical oligoarthritis
-Sacroilitis
-DIP predominant
-arthritis mutilans (telescoping)

Signs
-psoriatic skin lesions
-enthesitis, tenodynovitis, dactylitis
-nail pitting, onycholysis

Xray
-erosive changes and bone formation
-periostitis
-PENCIL IN CUP

Similar to RA but mild disease = NSAID
Moderate/severe = methotrexate
Monoclonal AB considered - ustekinumab, secukinumab

Question 4

Reactive arthritis
-pathophysiology
-risk factors
-presentation

Answer 4

Sterile arthritis developing 1 month post STI, food poisoning
HLA B27

Can’t see, pee, climb a tree
-urethritis, conjunctivitis, enthesitis, dactylitis, feet rash
-multiple peripheral/axial arthritis

Diagnosis of exclusion
ESR, CRP - elevated in acute, normalise if chronic
RA, ANA - rule out RA, SLE
Evidence of preceding infection - urinalysis, stool culture if symptomatic
Joint fluid aspiration - culture negative, rule out septic
Imaging - sacroilitis, enthesitis

Symptomatic - analgesia, NSAIDs
Sulfasalazine/methotrexate if persistent but disease rarely lasts more than 1 month