Case Reumatismo, 2012; 64 (3): 175-179 report Elbow monoarthritis: an atypical onset of juvenile idiopathic arthritis A. Marino, I. Pagnini, S. Savelli, D. Moretti, G. Simonini, R. Cimaz Unità di Reumatologia Pediatrica dell’Ospedale Pediatrico, A.O.U. Meyer di Firenze, Italy summary Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic condition in childhood and an im- portant cause of short and long term disability. Oligoarthritis is defined as an arthritis that affects four o fewer joints during the first 6 months of disease. The large majority of patients within this category belongs to a quite well defined disease which is not observed in adults. It is characterized by an early onset (before 6 years of age), an asymmetric arthritis involving mainly large joints, a female predilection, a high frequency of positive antinuclear antibodies (ANA), a high risk for developing chronic iridocyclitis and consistent HLA associations. We describe 3 clinical cases who presented monoarthritis of the elbow as early sign of oligoarticular JIA. All patients showed inflammatory markers elevation and 2/3 were ANA positive. MRI showed the presence of synovial inflammation without bone involvement. Intraarticular triamcinolone hexacetonide, led to remission in one case, while in the other two there was a re-activation of the disease treated with NSAIDs and/or MTX. The reported cases represent 0.6% of 490 patients with JIA followed by our unit in the last 10 years. Cases of exclusive involvement of the elbow at onset of JIA in literature are rare. Therefore, we report 3 cases of mono- arthritis of the elbow as initial sign of oligoarticular JIA, a very atypical onset of this disease. Key words: Elbow arthritis, juvenile idiopathic arthritis, monoarthritis. Reumatismo, 2012; 64 (3): 175-179 n INTRODUCTION 150 and from 2 to 20 out of 100,000 chil- dren. Oligoarticular JIA is characterized by uvenile idiopathic arthritis (JIA) is the early onset, usually before 6 years, female Jmost common chronic rheumatic con- predominancy and frequent positivity for dition in childhood and it is an important anti-nuclear antibodies (ANA) and is asso- cause of short- and long-term disability. ciated with a high risk of developing chron- JIA is not a single pathological entity, but ic iridocyclitis. Clinically it affects prima- a term which regroups all arthritis starting rily lower limbs, mainly knees and ankles. before 16 years, lasting for more than 6 Monoarticular involvement at the onset is weeks and have unknown etiology. So JIA frequently observed, usually as a monoar- is an exclusion diagnosis. thritis of the knee (3-6). A study performed A possible etiopathogenetic hypothesis is on a population of ANA-positive patients the exposure to ubiquitous environmental showed that 3/4 of the subjects were pre- agents, even though none has been consist- senting at the onset a monoarthritis, usu- ently identified in subjects genetically pre- ally at the knee, while the involvement of disposed (1). The most recent classification the elbow could be observed only during has been proposed by International League the following phases of the disease and of Associations for Rheumatology (ILAR) only in association (7). We describe 3 and recognizes 7 major categories (2). clinical cases of children followed by our Among these, the most frequent is oligoar- unit of Pediatric Reumatology in Meyer ticular JIA, indeed is estimated that from Children’s Hospital in Florence, presenting Corresponding author: 50% to 80% of all caucasian children af- monarthritis of the elbow as single initial Dott. Achille Marino Unità di Reumatologia Pediatrica fected by JIA in Europe and north America manifestation of oligoarticular JIA. This dell’Ospedale Pediatrico belong to this category with prevalence and site of presentation is strongly atypical at AOU Meyer di Firenze Viale Pieraccini, 24 - 50139 Firenze, Italy incidence respectively varying from 16 to the onset of this disease. E-mail: [email protected] Reumatismo 3/2012 175 Case report A. Marino, I. Pagnini, S. Savelli, et al. n CASE REPORTS JIA was diagnosed. Intraarticular steroid administration with triamcinolone hexac- Case 1 etonide was performed, followed by good C.A. is a 3-year-old female, referred to our clinical response. Uveitis has never been Hospital for sudden onset of swelling, pain detected during the follow-up. Two months and functional limitation of the left elbow. after arthrocentesis a flare on the left elbow Clinical examination was normal, except occurred, associated with left wrist arthri- for arthritis of the left elbow. Blood tests tis. So, treatment with methotrexate (MTX, showed inflammatory markers increased dose: 15 mg/mq/week) was started. (CRP 4.11 mg/dl, nv: <0.50 mg/dl; ESR 87 mm/h, nv 2-31 mm/h), mild anemia (Hb Case 2 10.7 g/dl, nv 12-14 g/dl) and ANA positiv- C.Y. is a young girl of 15 years of age, re- ity (1:640 titer, subsequently confirmed). ferred to our Unit for pain on the left el- Purified protein derivative (Mantoux) skin bow, without improvement after 5 months test and Quantiferon-TB tests were nega- of NSAIDs therapy, prescribed by other tive. Radiography of the left elbow was nor- physician. At admission, clinical examina- mal, while ultrasonography showed joint tion showed swelling and flexion contrac- effusion, swelling of the periarticular soft ture of the left elbow. Blood tests showed tissues and significantly increased blood increase of inflammatory markers (ESR flow on the affected site. To complete di- 43 mm/h, CRP 0.76 mg/dl). HLA-B27 and agnostic procedures, an MRI with contrast ANA titer were negative. Ultrasonography was performed revealing an extended area showed the presence of an hypoechogenic of swelling of the left elbow, synovial hy- film under the tricipital tendon, while MRI perplasia and extended synovial pannus, as with contrast showed a large joint effu- in inflammatory arthritis. For the atypical sion with synovial thickening (Figure 1). onset manifestations an oncologic-ortho- To complete diagnostic procedures a total paedic clinical evaluation was performed body bone scintigraphy was performed, and suggested needle synovial biopsy. and it confirmed increased activity on the This showed a diffuse inflammatory infil- left elbow. Malignancy and infections were trate, without atypical proliferation and/ excluded, so a diagnosis of oligoarticular or microorganisms. Thus malignancy and JIA was made. Intraarticular steroid ad- infections were excluded, so oligoarticular ministration with triamcinolone hexaceto- a b Figure 1 - two MrI images of the elbow before (1a) and after (1b) contrast: articular capsule appears stretched by serous fluid effusion with thickening of synovial linings (1a). In figure 1b contrast enhancement is showed. 176 Reumatismo 3/2012 Case Elbow monoarthritis report nide was performed, followed by rapid res- n DISCUSSION olution of symptoms and signs of joint in- flammation. Four months later, left elbow Arthritis of the elbow is rare, and usually arthritis recurred, and a trial with NSAID follows a trauma. Before diagnosing an was made with good response. At the last atypical onset of juvenile idiopathic arthri- examination, after 2 years of follow-up, tis it is necessary to exclude all other possi- the girl was healthy without therapy and ble causes, in particular orthopaedic (8, 9) articular examination was normal. No ocu- or infectious disorders. Etiological agents lar manifestations were described during more frequently involved in septic and follow-up. reactive arthritis are Staphyloccocus au- reus, Streptococcus pneumoniae, group A Case 3 Streptococcus beta haemolyticus, Borrelia C.A., 6 year-old female, complained of burdgoferi for Lyme disease, and enteric pain at left elbow and morning stiffness. and genital bacterial infections (Chlamydia Two months later she was referred to our trachomatis, Yersinia enterocolica, Unit. General physical examination was Salmonella, Shigella, Campylobacter). normal, except for swelling and function- Viral arthritis is rare in pediatric age, more al limitation on the left elbow. Blood test frequent in adults (10). showed increase of ESR 40 mm/h, while Other possible causes of non-infectivous CRP and Hb were normal, ANA was posi- arthritis in childhood are hemarthrosis, tive (1:640). Ultrasonography of the left in haemophilia (11), malignancy such as elbow showed articular effusion with syno- acute lymphoblastic leukemia (12), neu- vial thickening; MRI with contrast showed roblastoma, osteoid osteoma (13), syno- articular effusion, synovial thickening with vial chondrosarcoma (14) and aponeurotic contrast enhancement, due to synovial pan- fibroma (15). Gaucher disease and sickle nus. Malignancy and infections were ex- cell anemia can cause articular pain crisis. cluded, so a diagnosis of oligoarticular JIA Rare causes of elbow chronic monoarthri- was made. Intraarticular steroid administra- tis, such as tubercolosis, mostly in those tion with triamcinolone hexacetonide was countries in which the disease is endemic performed, followed by rapid resolution of (16), Blau syndrome (17) and villonodular symptoms and signs of joint inflammation. synovitis should also be considered (18). Slit lamp examinations were negative. After Recurrent involvement has been described 2 years of follow-up, the child is in com- in occult celiac disease or other autoin- plete clinical remission without therapy. flammatory diseases (19) (Tab. I). Table I - Conditions that more frequently mimic juvenile