Elderly patients presenting with musculoskeletal symptoms such as painful, swollen or stiff jointsare challenging to physicians. The        common conditions encountered      are osteoarthritis, crystal arthropathies, spondyloarthropathies and rarely seropositive arthritis. RS3PE highlights a different inflammatory disease involving the ten synovia of the tendons of the hands with a characteristic presentation. This case details such a presentation and aims to raise awareness amongst general physicians.

An 83-year-old man, with a history of chronic leg ulcers and poor mobility presented following a fall.at home. On admission he also complained of a six-to-eight-week history of bilateral hand swelling. This was of sudden onset, initially on the right hand and gradually progressed until the time of admission when it became prominent over the dorsum of both hands. Both hands were initially tender, but painfree at rest, and restricted in movement due to the swelling. Lately he had also noticed mild inactivity stiffness in his knees and shoulders, He had no previous musculoskeletal history, no skin rash or trauma to his hands.

Inspection of his hands revealed bilateral, symmetrical swelling, involving all the fingers and more pronounced on the dorsum.

On palpation there was pitting oedema over the dorsum

without signs of synovitis or joint deformity. (Figure 1 and 2).

On movement, finger flexion and opposition were limited, with reduced grip strength.

There was no girdle muscle weakness or pain. There was pitting oedema of both feet, with compression bandaging to the upper calf. This was chronic, and was likely to

peripheral vascular insufficiency.

Fig 1: Swollen hands

Fig 2: Dorsal pitting edema

Blood tests during this admission showed normocytic anaemia with low vitamin B12 levels but normal ferritin. Erythrocyte sedimentation rate (ESR) was raised at 100mm/hour and initial C-reactive protein (CRP) at 55 mg/l. Anti-nuclear antibody (ANA) and rheumatoid factor were negative. X-rays of the hands revealed mild osteoarthrosis without any evidence of bony erosions. Computerized tomography (CT) of the chest and abdomen did not show any evidence of malignancy.

In view of the clinical presentation and seronegativity, a diagnosis of peritendinous rheumatoid arthritis was considered. He was commenced on low dose oral steroids following initial parenteral corticosteroid. Subsequent to the initiation of steroids, there was dramatic resolution of the swelling of the hands, within a week (Figure 3),

Fig 3: Response to steroids

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome was first described by McCarty et al in 1985 1 . It is also termed as peritendinous rheumatoid arthritis in Europe.

It predominantly affects elderly males and although not exceptionally rare, there is no clear documentation of the incidence of this condition (2).

The syndrome is a subset of symmetrical polyarthritis characterized by

1. Bilateral pitting oedema of both hands
2. Sudden onset of polyarthritis (A few cases report patients being able to state the time to the hour at which this occurred.1)
3. Age >50 years
4. Absence of rheumatoid factor (seronegativity).

Other features include symmetrical distal synovitis and tenosynovitis affecting the synovial sheaths of the flexor and extensor tendons of the hands and/or feet without evidence of joint erosions 2. It responds dramatically to corticosteroids with long term remission after withdrawal, suggesting a benign prognosis.

Although generally thought to be a characteristic benign syndrome with good outcomes, several studies have been published linking RS3PE to various rheumatic disorders such as spondyloathropathies, psoriasis (HLA associations), polymyalgia rheumatica, and temporal arteritis. 3 It may also be a paraneoplastic manifestation of hematological or solid malignancies 4 (eg. prostate, rectal, gastric and ovarian tumors) linked to the synthesis of interleukin, IL-6. Review of these cases suggested that RS3PE associated with neoplasia was associated with a poor response to steroid treatment. 4 Although MRI scanning offers the best imaging technique to diagnose the condition.,RS3PE is a clinical diagnosis. Scans typically demonstrate the tenosynovitis of the extensor tendons believed to cause the oedema which characterizes the syndrome.3 MRI scans are valuable to exclude other bony pathologies like osteomyelitis.. An alternative imaging technique for identification of extensor tenosynovitis is ultrasonography. 5 Treatment generally involves steroids, but in some cases the patient may respond to NSAIDs or gold therapy

Competing Interests: None Declared

1. McCarty, D. J., O’Duffy, J. D., Pearson, L., and Hunter, J. B. "Remitting Seronegative Symmetrical Synovitis with Pitting Edema: RS3PE Syndrome." JAMA, vol. 254, no. 19, 1985, pp. 2763-2767. DOI: 10.1001/jama.1985.03360230067036.
2. Sayarlioglu, Mehmet. "Remitting Seronegative Symmetrical Synovitis with Pitting Edema (RS3PE) Syndrome and Malignancy." European Journal of General Medicine, vol. 1, no. 2, 2004, pp. 3-5. DOI: 10.29333/ejgm/82684.
3. Oliveri, I., Salvarani, C., and Cantini, F. "Remitting Distal Extremity Swelling with Pitting Edema: A Distinct Syndrome or a Clinical Feature of Different Inflammatory Rheumatic Diseases?" The Journal of Rheumatology, vol. 24, 1997, pp. 249-252. DOI: 10.3899/jrheum.240249.
4. Sibilia, J., Friess, S., Schaeverbeke, T., et al. "Remitting Seronegative Symmetrical Synovitis with Pitting Edema (RS3PE): A Form of Paraneoplastic Polyarthritis?" The Journal of Rheumatology, vol. 26, 1999, pp. 115-120. DOI: 10.3899/jrheum.260115.
5. Agarwal, et al. "Remitting Seronegative Symmetrical Synovitis with Pitting Edema (RS3PE) Syndrome: Ultrasonography as a Diagnostic Tool." Clinical Rheumatology, vol. 25, no. 5, Oct. 2005, pp. 697-702. DOI: 10.1007/s10067-005-1143-8.