# Rheumatoid Arthritis Extra-Articular Manifestations

> Rheumatoid arthritis extra-articular features for NEET-PG Medicine, covering nodules, Felty and Caplan syndromes, lung, eye, vasculitis and cardiac disease.

- Canonical URL: https://prepelephant.com/topics/neet-pg/medicine/rheumatoid-arthritis-extra-articular-manifestations
- Exam / course: NEET-PG · Subject: Medicine
- Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team
- First published: 2026-10-14
- Last updated: 2026-10-14
- Reference basis: Harrison's Principles of Internal Medicine; Kelley and Firestein's Textbook of Rheumatology
- How to cite: "Rheumatoid Arthritis Extra-Articular Manifestations", PrepElephant, https://prepelephant.com/topics/neet-pg/medicine/rheumatoid-arthritis-extra-articular-manifestations

## Direct answer

Rheumatoid arthritis extra-articular manifestations are disease features outside the joints, the most common being subcutaneous nodules over pressure points. They tend to appear in seropositive patients with high-titre rheumatoid factor or anti-CCP antibodies and signal more severe disease. The exam-relevant set covers nodules, Felty syndrome, Caplan syndrome, lung disease, scleritis and rheumatoid vasculitis.

## What you must remember

- **Rheumatoid nodule:** a firm, non-tender subcutaneous granuloma over the olecranon, extensor surfaces and occiput, most common in high-titre seropositive disease; histology shows central necrosis ringed by palisading histiocytes.
- **Felty syndrome:** rheumatoid arthritis with splenomegaly and neutropenia, typically long-standing and seropositive, with leg ulcers and recurrent infections as the main complications.
- **Caplan syndrome:** rheumatoid arthritis with pneumoconiosis, producing multiple well-defined rounded lung nodules of about 0.5 to 5 cm, classically in coal miners and workers exposed to silica or asbestos.
- **Lung disease:** interstitial lung disease with a usual interstitial or nonspecific pattern, exudative pleural effusion with low glucose and low pH, and bronchiolitis obliterans; methotrexate pneumonitis must be excluded first.
- **Eye disease:** keratoconjunctivitis sicca is the commonest eye lesion, often from secondary Sjögren syndrome, episcleritis is usually benign, and scleritis is the serious form that threatens vision.
- **Vasculitis:** rheumatoid vasculitis causes mononeuritis multiplex, digital infarcts and leg ulcers, typically in long-standing seropositive disease with nodules.
- **Heart and kidney:** pericarditis is the most common cardiac lesion, accelerated atherosclerosis raises cardiovascular risk, and AA amyloidosis presents as proteinuria or nephrotic syndrome.

## Felty and Caplan syndromes side by side

Felty and Caplan syndromes are the two named combinations examiners test most often, and students mix them up because both add a second organ system to rheumatoid arthritis.

| Feature | Felty syndrome | Caplan syndrome |
|---|---|---|
| Added condition | Splenomegaly with neutropenia | Pneumoconiosis from coal, silica or asbestos |
| Typical patient | Long-standing, seropositive, nodular disease | Rheumatoid disease in a dust-exposed worker |
| Characteristic finding | Recurrent infection and leg ulcers | Multiple lung nodules of 0.5 to 5 cm |
| Main management | Treat RA; splenectomy or G-CSF for severe neutropenia | Treat RA; nodules need no specific therapy |

A neutropenic patient with RA and an enlarged spleen points to Felty syndrome, while new lung nodules in a miner point to Caplan syndrome.

Felty syndrome usually evolves over years of long-standing disease, and the falling neutrophil count is often the clue that prompts the diagnosis. Caplan nodules can appear in crops, may cavitate or calcify, and sometimes show up on a chest radiograph before the arthritis is obvious. Mixing the two up is the commonest mistake in this area, so the exposure history and the blood count should always be read together.

## Where the exam tries to catch you

Most lost marks come from blaming every new finding on rheumatoid arthritis itself.

- **Trap:** a miner with RA and new lung nodules labelled as ordinary rheumatoid nodules — **Correct:** multiple well-defined nodules in a dust-exposed worker suggest Caplan syndrome, which is a separate pulmonary pathology.
- **Trap:** fever and leg ulcers in RA with an enlarged spleen treated as vasculitis alone — **Correct:** check the neutrophil count, since Felty syndrome with neutropenia predisposes to recurrent bacterial infection.
- **Trap:** new interstitial shadowing on methotrexate attributed to the arthritis — **Correct:** methotrexate pneumonitis and opportunistic infection must be excluded before labelling it rheumatoid lung disease.
- **Trap:** a painful red eye in RA dismissed as conjunctivitis — **Correct:** deep, boring pain with a tender red globe suggests scleritis, which needs urgent ophthalmology review.

## Frequently asked questions

### Which RA extra-articular feature is seen most often on examination?

Subcutaneous rheumatoid nodules over pressure points such as the olecranon are the most common extra-articular manifestation of rheumatoid arthritis. They are firm and non-tender, and they are most frequent in patients with high-titre seropositive disease.

### How does Felty syndrome differ from Caplan syndrome?

Felty syndrome is rheumatoid arthritis with splenomegaly and neutropenia, causing recurrent infection and leg ulcers. Caplan syndrome is rheumatoid arthritis with pneumoconiosis, producing multiple well-defined lung nodules that often cause few symptoms.

### Which eye lesion in rheumatoid arthritis threatens vision?

Scleritis is the eye lesion in rheumatoid arthritis that threatens vision, causing deep pain, redness and possible scleral thinning. Episcleritis is commoner but usually benign and self-limiting, so the two must be distinguished on examination.

### Why must methotrexate pneumonitis be excluded in RA lung disease?

Methotrexate pneumonitis is a drug toxicity that mimics rheumatoid interstitial lung disease, so it must be excluded before attributing new shadowing to RA itself. It is usually managed by stopping the drug, which is a different approach from treating rheumatoid lung disease.

### Why is pericarditis significant in rheumatoid arthritis?

Pericarditis is the most common cardiac lesion in rheumatoid arthritis, and it is often silent on examination. Echocardiography can reveal it, and its presence often reflects active systemic disease.