Wednesday, 12 Dec 2018

You are here

The Diverse Fate of Seronegative Rheumatoid Arthritis

A Finnish Rheumatology Center followed 435 early, seronegative rheumatoid arthritis (RA) patients for 10-years and found that only 3% became erosive or seropositive RA. They also found that 32% could not be further reclassified, and that the remaining 65% evolve into another diagnosis, led by polymyalgia rheumatica (16%), psoriatic arthritis (11%), spondyloarthritis (9%), and osteoarthritis (10%).  

Between 1997-2005  they enrolled 1030 patients into the early RA clinic at the Jyväskylä Rheumatology Centre. They included 435 seronegative cases (42%), of whom 69% were women, and prospectively followed patients for a ten-year period.

Among the 435 seronegative cases, the 10-year outcomes revealed:

  • 13 (3%) could be reclassified as seropositive or erosive RA
  • 68 (16%) cases of polymyalgia rheumatica
  • 46 (11%) psoriatic arthritis
  • 47 (10.8%) seronegative spondyloarthritis 
  • 45 (10%) osteoarthritis
  • 38 (8.7%) spondyloarthritis
  • 15 (3.4%) plausible reactive arthritis
  • 10 (2.3%) gout
  • 17 (3.9%) pseudogout
  • 6 (1.4%) paraneoplastic arthritis
  • 6 (1.4%) juvenile arthritis
  • 2 (0.5%) haemochromatosis
  • 3 (0.7%) ankylosing spondylitis
  • 2 (0.5%) giant cell arteritis
  • 8 miscellaneous diagnoses.
  • 41 (9.4%) had transient arthritis
  • 49 (11.2%) remained were not reclassifed.

After an initial diagnosis of seronegativity, prolonged follow-up revealed significant heterogeneity and reclassification of the inital diagnosis. Therefore seronegative arthritis should not be considered as a homogenous entity.

(Editor's note: This is a very interesting study. I'm amazed that only 14% kept a diagnosis of RA, but this may be a regional issue. While many Scandinavian cohorts such as these may have more seronegative spondyloarthritis patients manifesting as polyarthritis, the diversity of other subsequent diagnoses is interesting, if not humbling. One thing said by Dr. Ronan Kavanaugh on RheumNow some time ago was that "In seronegative patients in remission for years always consider withdrawing DMARD". I would add to that by saying you should always consider alternative diagnoses the longer you call someone "seronegative" RA.)

Disclosures: 
The author has no conflicts of interest to disclose related to this subject

Add new comment

More Like This

CV Risks Similar in Systemic Sclerosis and Rheumatoid Arthritis

Interactions between disease-related inflammatory processes and the development of several morbidities have been well-studied in RA, particularly heart disease. This is not the case for the often-lethal SSc (estimated standardized mortality ratio between 2.5 and 4.0). Similarly, there are no studies comparing the most relevant comorbidities between SSc and RA.

PRAIRI Study - Can RA Be Prevented?

B-cell depletion may offer a means of delaying the onset of clinical arthritis in adults at high risk, according to the PRAIRI study - a proof-of-mechanism study in pre-clinical RA patients. 

Rheumatoid Lung Disease Imposes Significant Morbidity and Mortality

Insurance claims data were analyzed for the frequency of interstitial lung disease (ILD) associated with rheumatoid arthritis (RA) and finds that although rare, its frequency increased over time and it is associated with a significant mortality rate. 

The study was done because RA-ILD has been shown to cause significant morbidity and mortality. 

Growing Tick Population Comes with Health Concerns

CNN has published a recent government report from the Tick-Borne Disease Working Group that suggests the US tick population is growing and may bring with it an increase in tick-related illnesses. 

While Lyme disease is the most popular of tick-borne illnesses, there are another 20 known conditions related to tick bites.

Chikungunya Virus Vaccine Developed

Lancet reports on a new vaccine for Chikungunya fever (MV-CHIK) demonstraing excellent safety, tolerability and good immunogenicity, independent of pre-existing immunity against the vector. MV-CHIK is a promising vaccine for the prevention of chikungunya fever.