Rheumatoid Arthritis (RA)

🔍 When to Suspect

A symmetrical polyarthritis affecting the small joints of the hands (MCP, PIP) and feet (MTP), with associated morning stiffness lasting more than 30-60 minutes

From the full topic in The Ocean Library: Rheumatoid Arthritis (RA)

🧭 When to suspect

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease affecting around 1% of the UK population, roughly three times more common in women, with a peak onset between 40 and 60 years (though it can present at any age). Suspect RA in any adult with persistent synovitis – soft-tissue swelling, warmth and tenderness of a joint – that does not settle within a few weeks.

The classic pattern is a symmetrical polyarthritis of the small joints of the hands (metacarpophalangeal [MCP] and proximal interphalangeal [PIP]) and feet (metatarsophalangeal [MTP]), with early-morning stiffness lasting more than 30 minutes (often considerably longer) and prominent systemic fatigue.

The single most important task in primary care is early recognition and rapid referral. There is a narrow “window of opportunity” in which disease-modifying therapy can prevent irreversible joint destruction, so referral is made on clinical grounds and must never be delayed while awaiting blood tests or X-rays – these are frequently normal in early disease. Smoking is the strongest modifiable risk factor.

Feature	Inflammatory (RA)	Degenerative (osteoarthritis)
Early-morning stiffness	Prolonged, > 30 min (often > 1 hour)	Brief, < 30 min; stiffness after rest
Pattern	Symmetrical, polyarticular	Often asymmetrical
Joints typically involved	MCP, PIP, wrists, MTP (spares DIPs)	DIPs, first carpometacarpal, knees, hips
Effect of activity	Eases with movement	Worsens with use, eases with rest
Systemic features	Fatigue, malaise common	Absent

🧠 Clinical pearl In RA the distal interphalangeal (DIP) joints are characteristically spared. Prominent DIP involvement should instead prompt thoughts of osteoarthritis or psoriatic arthritis (look for nail pitting, dactylitis and a personal or family history of psoriasis). Asymmetry, a single hot joint, or a rapid severe attack points elsewhere – gout, pseudogout or septic arthritis.

Source: NICE NG100 · NICE QS33

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