Carol - Ankylosing spondylitis versus psoriatic spondyloarthropathy

[Guest guest]

Carol, sorry it took me so long to get back to you on all of this, but,

as you can see below, I had trouble keeping this short.

Confusingly enough, you don't have to have psoriasis to receive a

diagnosis of psoriatic arthritis (PsA). Psoriatic spondyloarthropathy

(psoriatic spondylitis) is a subset of psoriatic arthritis. Psoriatic

arthritis is in a general grouping of diseases referred to as

seronegative spondyloarthropathies or, simply, spondyloarthropathies

(SpAs). Ankylosing spondylitis (AS) is in that group as well.

http://www.spondylitis.org/html/htmlpages.asp?load=reactive_what.htm

http://www.emedicine.com/med/topic1954.htm

http://www.psoriasis.org/b300.htm

Even in a patient with no psoriasis, a family history of psoriasis will

often be enough to lead a physician to consider one of the

spondyloarthropathies. Sometimes a patient is unaware of having any

psoriasis until his or her physician finds a small hidden patch on the

scalp, in the navel, or at the base of the spine, for example.

Some estimates are that as many as 15-20% of psoriatic arthritis

patients develop the arthritis before any sign of psoriasis.

I've been mulling over your possible RA and AS combination. I'm assuming

that your rheumatologist hasn't actually given you that dual diagnosis

yet and that he is merely thinking aloud. Since concurrent RA and AS is

rare, I would want a stronger argument to support such a long-shot

diagnosis before accepting it. At the moment, you are RF-negative and no

radiographic studies have been done to investigate either the RA or AS

possibilities. There are many, many causes of low back pain and/or

inflammation - AS is not the most common one. I think, too, that most

rheumatologists would be unwilling to give an AS diagnosis without some

radiographic evidence.

Here is an excerpt from a rheumatology text:

" The distinction of AS from RA is usually not difficult. Patients with

RA usually have polyarthritis which is symmetric in distribution and

affects small and large joints of the extremities; involvement of the

SI, apophyseal, and costovertebral joints is very rare. In AS on the

other hand, any involvement of peripheral joints (other than hip and

shoulder joints) is oligoarticular and asymmetric, affecting more often

the larger joints of lower extremities; serologic tests for rheumatoid

factor are negative; and subcutaneous nodules are absent. There are rare

instances of concurrent AS and RA. "

Source:

http://www.ascare.org.tw/CLINICAL.htm

Your doctor is correct in saying that lumbar involvement in RA is

atypical and hand involvement is not common in AS, but would either of

those occurrences be more or less rare than a combination of RA and AS?

Or could it be something else altogether? Something more probable that

would still explain your clinical presentation? A seronegative

spondyloarthropathy that affects both the hands and lumbar spine? I

don't know. But, for example, you might wonder if psoriatic

arthritis without psoriasis would be more or less common than

concurrent RA and AS. Again, I don't know.

Maybe it is RA plus some other cause of your lower back problems. What

about RA and fibromyalgia? RA and osteoporosis (have you ever had a bone

mineral density test since your hysterectomy?)? RA and a gynecological

problem?

You asked me in another post if RA plus AS would necessarily mean a

worse prognosis. I think I would concentrate on figuring out if this is

really your diagnosis first, even if that means waiting for further

tests or developments or getting a second opinion. RA and AS is

possible, but is a very uncommon combination. But I'm just thinking

aloud, too. I'm not trying to make you doubt your physician, but

cautioning you that keeping an open mind about your diagnosis,

especially in the beginning when the facts are still evolving and being

discovered, is probably a good idea.

RE: [ ] Ankylosing spondylitis versus psoriatic

spondyloarthropathy

> Thanks, . That's very interesting! The only confusing thing is I

have

> no psoriasis. Do you have to have it to have psoriatic

> spondyloarthropathy?

>

> Hugs,

> Carol