RA or PsA: What’s the Difference?

Red-hot, swollen joints lead to excruciating pain.  Patients, writhing in agony, phone their doctors for help.  For the lucky, a quick diagnosis is made:  rheumatoid arthritis.  The luck is in the speedy diagnosis, not in the unfortunate diagnosis itself.

Often the diagnosis is unclear.  Doctors aren’t sure what the problem is, or even if there is a problem.  Alas, it’s not unusual for busy doctors to give hurting people in this situation the brush-off with, “It’s all in your head.”  If  your disease doesn’t match the pattern described in textbooks (atypical presentation), it’s hard for doctors to recognize.  Diagnosis of autoimmune disease can take years.

Even when a doctor determines that autoimmunity is the culprit, it might not be clear exactly which disease is causing the problem.  Many have very similar symptoms. Fortunately, arthritic diseases caused by a faulty immune system respond to similar medicines.  In order to get insurance to cover treatment, a diagnostic-label is sometimes affixed despite the uncertainty.  Over time, the uncertainty is forgotten and the tentative label takes on a life of its own.  Maybe it doesn’t matter.  After all, at least the patient gets treated.

Then again, maybe accurate diagnosis wherein different diseases are clearly distinguished would lead to better data about which medicines would be most likely to help a given patient.  It’s maddening to suffer through years of trial-and-error hoping to find effective treatment. When rheumatologists evaluate a new patient with autoimmune arthritis, one question is, “Is this rheumatoid arthritis, or is it psoriatic arthritis (or is it something else entirely)?”  Keys they look for are 1) nail involvement, and 2) skin psoriasis.  There is no nail involvement in RA.  In PsA, 80% of patients have nail symptoms such as ridges, grooves, and/or pitting.  Psoriatic finger/toenails can thicken instead of growing longer, sometimes even crumbling or falling off.  The problem with using nails as diagnostic criteria is that, according to the National Psoriasis Foundation, 20% of PsA patients do not have nail symptoms.  I propose that looking for ridged nails without asking about ridged nails is an exercise in futility, since people with unsightly nails might address the issue.  Furthermore, according to the American College of Rheumatology, “Psoriatic arthritis can occur in people without skin psoriasis, particularly in those who have relatives with psoriasis.”  In fact, in juveniles, up to half of PsA patients experience arthritis symptoms before there is any skin involvement.  Obviously we have a problem.

Dr. Irwin Lim, rheumatologist, writes:

Many patients labeled as having “Seronegative Rheumatoid Arthritis” or “Seronegative Inflammatory Arthritis” may have Psoriatic Arthritis.

In two short video clips, he explains more:

Not all patients with the diagnosis of psoriatic arthritis will have skin manifestations. Sometimes the diagnosis is made from a collection of other symptoms and signs, and a positive family history. Sometimes the rash actually occurs years after the development of psoriatic arthritis. So, it’s definitely possible to have psoriatic arthritis without the skin psoriasis.

Psoriatic arthritis can be very difficult to diagnose. It really does require the doctors to have a high index of suspicion. In patients who already have psoriasis affecting the skin or nails, the diagnosis is much easier because most people would think about it. But, sometimes, the symptoms can be quite vague. So many people have back pain, and it’s often explained away. In addition, joints aches and pains are common in the community, and sometimes the link with psoriatic arthritis is not put together. So, typically the diagnosis is made by an experienced physician taking into account the history, the examination, and the clinical context.

He is not alone in his views.  Doctors Jaya Philipose, MD and Atul Deodhar, MD write

The diagnosis of psoriatic arthritis (PsA) often is missed, partly because patients may present with inflammatory spinal pain, tendinitis, enthesitis, or dactylitis rather than a “true arthritis.”

It’s important to note that the rheumatologist is looking for clues at a single moment in time. In contrast, the patient knows a lifetime’s worth of history. If patients know the types of patterns that doctors are looking for, we can better provide the information that our doctors need to make an accurate diagnosis.

Usually doctors looking at family history are only interested in first-degree blood relatives:  parents, children, and full-siblings.  When considering psoriasis, though, doctors are also interested in second-degree relatives:  grandparents, grandchildren, half-siblings, aunts, uncles, nieces, and nephews.  Contact family members and ask.  Don’t just ask about psoriasis.  Ask about rashes and flakey skin.  Ask about severe dandruff — on the elbows and knees as well as on the scalp (not everyone is going to see a doctor for a diagnosis of those flakes).  See if  you can find a pattern.  Patterns can help your doctor make a diagnosis.

Following is a chart comparing some of the similarities and differences of RA & PsA:

PsAvsRA

For further reading:

Dr. Google

You don’t have to read medblogs for long to learn that doctors do not appreciate it when patients research symptoms on the internet, then show up for an appointment with printouts.  Irritating the person who’s supposed to be helping us isn’t a good idea, so it makes sense to not take printouts to appointments.

That doesn’t mean patients can’t read reliable websites (Up-to-Date and Mayo Clinic are good places to start).  It just means that we ought not tell the doctor how to do his/her job.  It goes over much better if we don’t provide a diagnosis; patients provide symptoms and let the doctor come up with a diagnosis.  At least that’s what the medblogs say.

But what if the doctor’s diagnosis is wrong?

I’ve written before about the red sores that my rheumatologist and family physician thought might be psoriasis, but my dermatologist diagnosed as nummular dermatitis.  Those &#%$ spots show up if I miss one of my cimzia/mtx injections, and take a couple months to go away — unless I dig into my stash of prednisone, in which case they are gone in a couple weeks.  It’s obviously something related to the RA, but what?

Well, recently I googled another symptom (completely unrelated, I thought) that has plagued me for well over a year.  I find it bothersome, but not something I’d dream of making an appointment about. It certainly would never come up in the course of conversation at the doctor’s office.  However, in reading the differential diagnosis for that symptom, up popped vasculitis.  Really?  Others with RA have mentioned vasculitis, but I didn’t know much about it, so started reading.  The articles include photographs of red sores, mainly on the legs, that look very much like what my dermatologist said is something completely different. Reading about vasculitis is frightening, so I hope that’s not what this is.  But I need to know.

At my next appointment, I think I will ask if it’s possible that those red blotches all over my skin could be vasculitis instead of nummular dermatitis. The trick is finding out without annoying my doctors.

Does It Really Matter What We Eat?

How much do we really need to eat? What kinds of foods provide the best fuel for our bodies?  How do we know?

A year ago, Andrew did an excellent series about metabolic syndrome.  In part 3, he mentioned a book, which I bought.  Like many books, The Insulin-Resistance Diet has a could this be you? list:

A family history of diabetes, overweight problems, abnormal cholesterol or triglycerides, heart disease, or stroke.  yes, yes, yes, yes, and yes

Frequent cravings for sweet or salty, crunchy snack food. no – well, unless you count and skittles and pralines, and… okay, maybe that’s a yes

This was not a happy beginning to the list, but I continued, and before long said, “Wait! How many ‘yes’ answers do you need before this is something to be concerned about?”  Well, it turns out the answer is three, and when I finished the risk-test, I had a whopping thirteen yesses!  Most depressing.  It could, however, explain why all my clothes seem to have shrunk (and I can’t blame prednisone this time).

What struck me when reading the book were the similarities between this diet and the Zone. The Zone, in turn, has some similarities to Atkins.  The biggest distinction between Insulin Resistance Diet and the others is that there are no restrictions on what can be eaten.  You can eat whatever you want as long as you have protein every time you eat.  With Atkins, by the second day people are climbing the walls with cravings for a piece of fruit or glass of orange juice.

After reading The Insulin-Resistance Diet, I re-read Dr. Atkins New Diet Revolution and Barry Sears’ The Zone: A Revolutionary Life Plan to Put Your Body in Total Balance for Permanent Weight Loss.  I own these because I inherited them from my father, who died of a heart attack at age 59.

As I continued looking for more information, I discovered Sears’ follow-up:  The Anti-Inflammation Zone, and a book by neurologist David Perlmutter: Grain Brain: The Surprising Truth about Wheat, Carbs, and Sugar–Your Brain’s Silent Killers.

These books all subscribe to a very different nutritional theory than the USDA and NHS.

NutritionTheoriesGovernment recommendations are that people should consume a significant amount of grains.  Really?  When we fatten up our cows for slaughter (the butcher will be here in a week), we bring them in off pasture and feed them lots of grain.  It should not surprise anyone that a diet rich in grains leads to weight gain — in people as well as cows.

How do we choose which theory to believe?  Lots of grains or no grains?  How do we know the best way to eat?  One thing I did was to look at credentials and motivation.

  • Dr. Atkins was a cardiologist who had spectacular results getting his patients to lose a lot of weight quickly.  Contrary to popular misconception, he only advocated extremely low carbs during the induction phase of his diet.  Long-term, his lifetime eating plan is quite similar to the carbs recommended by both Sears and Perlmutter.
  • Barry Sears is a well-respected researcher who comes from a family in which the men all die of heart attacks in their 50’s; he was searching for the truth to prolong his own life, not dabbling around in the lab looking to support the pet theory of his financier.
  • Dr. Perlmutter is a neurologist who found a common thread between diet and metabolism; he has helped patients with a variety of ailments, and refers to a number of credible studies in explaining the affect of food on our health. Lustig, Phinney & Volek  have similar work that is cited by Dr. Perlmutter.
  • The nutritionist and physician who wrote Insulin-Resistance Diet have helped people lose weight after all other diets failed them.

Those are all much better credentials than a theory based on research done to prove that a vegetarian diet is superior to any other — which (rumor has it) is where the food pyramid came from.  What if the government quit subsidizing wheat, corn, and soy farming, and started subsidizing green beans, lettuce, and spinach? Would that lead to a change in the USDA’s dietary recommendations?

It’s interesting to compare these theories.  What’s the same?  What’s different? What will work?

Zone and IRD both recommend consuming protein and carbohydrates in specific proportions.  7 g protein to 9 g carbohydrate for the Zone, and 7g protein to 15 g carb in IRD.

PCFZone

Atkins takes a slightly different approach, claiming that people whose diet has been drastically out of balance due to overconsumption of starchy foods and under-consumption of protein ought to compensate by first eating plenty of protein and no starchy foods; then, as excess weight comes off, increase healthy carbs to a more appropriate balance between carbs and protein.  Grain Brain, too, starts out recommending very low carbs, then increases after a month

All of these dietary plans reach the same conclusion:  It does matter what we eat.  To be healthy, people need to eat the right foods in the right proportions.

The reason this matters is something that I will elaborate on in a future post. Sears & Perlmutter are both adamant that there is a link between diet and autoimmune diseases.

To be continued…