INFO - What is a rheumatoid nodule?

[Guest guest]

Histology

The rheumatoid nodule is composed of three histologic zones:

Outer zone of vessels, lymphocytes and plasma cells;

Middle zone of monocytes migrating from outer zone blood vessels to

the inner zone, with the phenotype changing to activated macrophages

as they travel. These cells are arranged in a typical palisading

layer;

Inner zone of central necrosis composed of fibrinoid material,

collagen, reticulin fibers, cellular organelles, serum proteins.

Pathogenesis

The earliest lesion is a focal vasculitis of the capillaries and

venules, most likely resulting from immune complex deposition (large

vessel vasculitis is rare). Factors involved in the pathogenesis

include:

Genetic predisposition associated with HLA and TNF polymorphisms;

Trauma to small blood vessels at points of pressure causing local

pooling of immune complexes;

Activation of macrophage by immune complexes;

Production of pro-inflammatory cytokines;

Tissue necrosis by collagenases, proteinases, and cytokines.

Clinical Features

Rheumatoid nodules are present most commonly in men with a high titer

rheumatoid factor who have active articular disease. Nodules are

reported in 20-25% of cases of rheumatoid arthritis, and correlate

with worse articular and extra-articular manifestations and poor

function.

They are often located over pressure areas, such as the elbows and

feet, but are also found where direct trauma plays no role, such as

the lung, larynx, eyes, heart, meninges, bladder.

The differential diagnosis of the rheumatoid nodule includes:

Granuloma annulare;

Necrobiotic lipoidica diabeticum;

Tophi, xanthomatosis;

Multicentric reticulohistiocytosis;

Basal cell carcinoma.

Complications of rheumatoid nodules include:

Pain;

Limited joint mobility;

Neuropathy;

Ulceration;

Fistula formation;

Infection.

Surgical removal is an option for any of the above complications, but

nodules tend to reoccur in as little as a few months when they are

present over an area of repeated trauma. Intranodular steroid

injections may reduce the size of the nodule.

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Read the entire case study here:

http://www.hopkins-arthritis.org/physician-corner/case-rounds/case6/6_case.html

Not an MD

[Guest guest]

I did not like having nodules on my elbows! After I started using

Enbrel, they disappeared. Thank goodness. My aunt, who had RA, had

huge nodules on her elbows. Because of them, she always wore long

sleeves.

Sue

On Sep 1, 2010, at 9:04 PM, wrote:

>

> Surgical removal is an option for any of the above complications, but

> nodules tend to reoccur in as little as a few months when they are

> present over an area of repeated trauma. Intranodular steroid

> injections may reduce the size of the nodule.

[Guest guest]

How would you tell the difference between internal RA nodules on your organs and

what would be diagnosed as cysts? Does anyone know?

OKD