Pediatric Rheumatology Online Journal

Vol 2, No. 2   2004 (114-118)

http://www.pedrheumonlinejournal.org


SPECIAL ARTICLE

What is the Significance of Dry Synovitis?

 

Barbara E. Ostrov, MD

Professor of Pediatrics and Medicine

Chief, Division of Pediatric Rheumatology

Pediatric Rheumatology and Rheumatology

PennState College of Medicine

The Milton S. Hershey Medical Center

Hershey, PA 17033

 

Introduction

As pediatric rheumatologists, the finding of swollen, boggy joints is helpful when definitively diagnosing the various forms of juvenile idiopathic arthritis (JIA).  In addition, change in the synovitis allows accurate monitoring of our patients as we treat them.  However, when we see patients with minimal swelling but stiffness along with flexion contractures as well as other evidence of an inflammatory process (lab changes and/or other symptoms, such as uveitis or rash), the presence of “dry” synovitis must be considered. 

 

Case example

The patient is a 19 year old who presented at 9 years of age with high spiking

fevers, leukocytosis, severe microcytic anemia, ESR of 85 mm/hr and a diffuse polyarthritis.  A diagnosis of systemic JIA was made.  He never had recurrence of the systemic features subsequently, but had a persistent polyarthritis (“systemic onset with a  polyarticular course”) associated with severe morning stiffness.  He improved with high dose then tapered doses of corticosteroids, along with NSAIDs and methotrexate as well as physical therapy.  Over the next 5-6 years, his disease was well controlled with this regimen except for hand and hip stiffness.  Hip radiographs revealed joint space narrowing bilaterally.   He had persistent stiffness and diffuse flexion contractures with minimal swelling of all hand joints.

In 1999, etanercept was added to his regimen.  Within 4-6 months time, the residual hand contractures completely resolved; the steroids were ultimately discontinued.  No hand stiffness remained and he was able to make a fist normally.  Some residual bony hypertrophy was noted of his PIP and DIP joints.  His hip range of motion was mildly limited but no hip pain or morning stiffness are reported. 

He is currently stable on etanercept twice a week, indomethacin twice a day and weekly injected methotrexate.  This is an example of dry synovitis of hand joints in JIA.  This case exemplifies the lack of response of the dry synovitis to methotrexate and low dose steroids but resolution of this type of synovitis once etanercept was added to the patient’s regimen.

 

Development of criteria for dry synovitis

In 1974, Levinson gave a detailed description of “dry” synovitis:  “… little overt synovitis, but the gradual development of limitation of movement and appearance of deformities… no systemic features and there is little in the way of constitutional disturbance.”  [Levinson J.  JRA, Current Diagnosis 4 (Editor F. Howard), 1974;  Saunders, Phila.]   This description was reiterated by Ansell [Ansell BM, Arden Surgical Management of JCA.  1978] and she emphasized its presence in polyarticular juvenile arthritis. 

There are almost no references to “dry” synovitis in more recent web-based or printed publications.  Dorland’s On-Line Medical Dictionary defines it as “synovitis but with little effusion.”   In a search of MedLine in February, 2003, only one reference including this term was mentioned in a child with eosinophilic fasciitis [Patrone and Kredich;  Am J Dis Child;  1984; 138:363-5].  Scleroderma and related disorders, not surprisingly, often present with hand joint contractures and minimal synovial bogginess, which would be typical of “dry” synovitis.  Other than these situations, no cases of dry synovitis in other connective tissue diseases have been reported.

But - are there other differences between “dry” and “wet” synovitis in JIA?  Does this finding signify a “scleroderma-like” process?  Do these variants respond differently to therapy?  If there are significant differences between patients with “dry” versus “wet” synovitis, then possibly drug and treatment trials need to separate these groups.  Finally, is there a difference in prognosis between these forms of arthritis?

In order to answer these questions, we need to begin by setting preliminary criteria for diagnosing “dry” synovitis.  Then, we can assess its’ presence in our patient population and the response to current therapies.  It would be important to determine if there are any differences in response to therapy, especially as newer drugs, including additional biologics, become available.

 

Preliminary Criteria:

 

Joint pain and stiffness reported in the patient history for at least 3 months.

 

PLUS: minimal joint effusion and minimally palpable synovial tissue on examination.

 

AND: association with the following 3 criteria:

 

1.      morning stiffness of > 1 hour

2.      loss of range of motion, with or without contractures, of involved joints detected on physical examination

3.      improvement in the symptoms and physical findings with appropriate medical therapy

 

 

 

Retrospective Chart Review:

A retrospective chart review of 50 sequential out-patient visit charts of children with JIA, was performed to determine which subsets were most associated with the presence of dry synovitis using the above criteria.  Only those patients followed and treated for at least 6 months were included in my chart review. 

 

Diagnoses with inflammatory arthritis:

 

 

Wet synovitis (number / %)

Dry synovitis (number / %)

Both

(number / %)

Pauciarticular JIA

18 (100%)

0

0

Polyarticular JIA

16 (70%)

8 (30 %)

8 (30%)

Systemic onset JIA

6 (86%)

1 (14%)

1 (14%)

 

Overall, of the 50 children, 17% had dry synovitis.  No child with pauciarticular disease had dry synovitis.  Dry synovitis almost always occurred exclusively in hand joints.

 

An attempt was made to review the differential response to various therapies between the patients (or joints) with dry synovitis versus wet synovitis (as in the case above).  However, since all the JIA patients with dry synovitis also had wet synovitis in other joints, this was impossible to assess retrospectively.   One thing appeared clear from the chart review (data not shown).  NSAIDs definitely were not adequate for the severe dry hand synovitis in the polyarticular and systemic JIA patients.  As in the case example, anti-TNF therapy seemed to make the most difference in those cases.

 

 

DISCUSSION

In order to try to answer the questions raised at the beginning of this dialogue, I would propose the following steps:

 

1.      Development of a multi-center prospective database to assess/revise the proposed preliminary criteria for the diagnosis of dry synovitis. It would be important to use the new ILAR criteria. 

 

2.      Use of the database to collect information on diagnosis and treatment of these patients.  Overlap diagnoses with features of scleroderma plus JIA would have to be clearly delineated. 

 

3.      Using the database, one could assess the differing response to therapy of children with dry synovitis versus wet synovitis.  Although it would be tedious, it would be important to assess the differing response to treatment of each type of synovitis (dry synovitis of hands versus wet synovitis of knees in the same patient, for example).

 

4.      If the database is collected over several years, a differential prognosis between these forms of synovitis may be noted.

 

5.      Based on these data, subsequent recommendations about the inclusion, exclusion or separation of these patients in research and drug therapy trials could subsequently be made.

 

The issue of dry synovitis is too much a matter of speculation and anecdotal opinion. It would be an important step to study dry synovitis with this or other efforts and change our opinions to more evidence-based medicine.

 

To comment on concept and proposal regarding dry synovitis please e-mail PROJ at lww@uchicago.edu.  Comments may be published in May/June PROJ issue.