Doing Some Detective Work to Find the Right Diagnosis

Some days in our rheumatology clinic, our staff feels like a detective agency. We need to work together and examine all of the clues before we’re able to finger the prime suspect. Sometimes we get it right the first time, and sometimes we have to slog through a long investigation that twists and turns.

Here are examples of each of these scenarios.

Anne is a recent patient who came to our clinic for the first time 18 months ago. She is a 37-year old female who developed psoriasis after the birth of her first child in her early 20s. Her skin issues were managed by a dermatologist, who prescribed topical agents to keep her symptoms at bay. This was generally successful for several years, but in early 2019, Anne began suffering chronic joint pain, especially in her fingers and toes. Three months after she reported this to her dermatologist, Anne was able to get on our schedule for her initial rheumatology appointment.

In many ways, this seemed like a slam dunk sort of case. Anne’s father had been diagnosed with psoriatic arthritis (PsA) more than a decade ago, and she had a daughter who was diagnosed with juvenile idiopathic arthritis at the age of 2 years old. Upon physical exam, we found several patches of psoriasis on Anne’s skin as well as a severely swollen toe on her left foot (ie, a “sausage digit”). With all signs pointing to a diagnosis of PsA, we started Anne on methotrexate and she responded quickly to treatment. So far, it looks like we’ve done all the right things without really having to tax our creativity very much. Mystery solved!

But then there is Denise, who has challenged our investigative skills for years. Denise was referred to us by her primary care provider shortly after her 45th birthday with pain in her bilateral hands and feet, “knots” in her joints, and left heel pain. The pain in her hands, Denise told us, had been present for the better part of the last 10 years, although her other symptoms had developed more recently. She had mostly self-managed her pain over the years with NSAIDs, though they only provided minimal, temporary relief.

This was a much more challenging case from a diagnostic perspective. Denise had no relevant family history or previous medical history for us to lean on, so we started with X-rays of the bilateral hands and feet, hoping that these might provide us with some additional clues.

X-rays of Denise’s feet appeared normal, but her hands showed significant osteoarthritis of the bilateral carpometacarpal (CMC) joints.

“Unfortunately, as with many of our rheumatology patients, the diagnosis is not always clear cut, and we often have to play a game of trial and error with medications and treatment plans.”

Findings were otherwise normal, so we agreed upon an initial diagnosis of osteoarthritis. We prescribed steroid injections into her CMC joints and referred her to a hand surgeon for further consultation. We thought we had cracked this case as well.

Not so fast. Denise was back in our office 2 years later, this time with bilateral knee pain and swelling. Her CMC joints had been replaced by the hand surgeon, but the pain was back in her hands, this time symmetrically across her interphalangeal (PIP) and metacarpophalangeal (MCP) joints. This caused us to revisit our initial diagnosis, and we began to suspect rheumatoid arthritis (RA). Consequently, Denise began taking hydroxychloroquine, intending to complete a 3-month course before an initial follow-up. We also ordered a new lab panel specific to RA—all values came back normal/negative.

At Denise’s next follow-up, she said her pain was only slightly better. Things were breaking down even further 3 months later, when there was obvious swelling in her wrists to go along with worsening levels of pain. An MRI of her wrists were ordered, showing numerous erosions and inflammation consistent with a diagnosis of seronegative RA.

We then started Denise on methotrexate. Again, there was some short-term improvement, but it didn’t last. Throughout the next decade, Denise cycled through a number of medications in an effort to try to control her symptoms. Infliximab worked for approximately 9 months, but because she lived 2 hours from our practice, the infusion schedule became too much of a burden. We then moved onto adalimumab, which she gutted through for 4 months before asking for something else due to painful injection site reactions. Since it appeared as if TNF inhibitors were effectively addressing Denise’s pain, we moved to a third drug in that class, etanercept. That was successful for a bit longer, nearly 2 years, before her flares started becoming a bit more frequent and she asked for another change. Given her options, Denise opted for golimumab due to the need for only monthly injections. A year later, we were looking for something else due to another burst of disease flares.

Since we had just about run through the current list of TNF inhibitors, it was time for a switch. Denise started on abatacept, then moved to tofacitinib, and then to rituximab. We were starting to run out of big guns, and nothing had provided sustained relief of Denise’s symptoms. We all have patients like this—it’s a real challenge to keep them motivated after round after round of failures.

Two years ago, we finally hit that “A-ha!” moment that changed our approach entirely. Denise came in with itchy skin over her elbows. Although there was no visible rash, Denise told us she had noticed changes in the appearance of her fingernails in recent months. A physical exam showed pitting of the nail beds along with onycholysis. That was when we realized we had gotten things wrong from the start. Denise’s diagnosis was now changed to PsA, and she started on secukinumab. Two years later, her symptoms remain well controlled. Hopefully, we’ve finally found the secret to long-term success.

I often wonder how Denise’s experience with our practice would have been different/better if we would have been able to figure out right off the bat that we were dealing with PsA. Unfortunately, as with many of our rheumatology patients, the diagnosis is not always clear cut, and we often have to play a game of trial and error with medications and treatment plans. It may look like a duck and act like a duck, but in rheumatology, it’s not always a duck. We are in a complex medical specialty that always keeps us guessing, forcing us to investigate and re-evaluate our patients like a criminal detective. The hope for our patients is that right answer is always out there if we can find and correctly interpret all of the clues.





AUTHOR PROFILE: Carrie Beach, BSN, RN-BC is a rheumatology nurse with the Columbus Arthritis Center in Columbus, OH, and the President-Elect of the Rheumatology Nurses Society

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