Diagnostic Rate of Autoinflammatory Diseases Evaluated by Fever Patterns in Pediatric- and Adult-Onset Patients.

OBJECTIVES: This is a noncomparative study performed to determine if fever pattern is related to a diagnosis of autoinflammatory disease (AID) in pediatric- and adult-onset patients. METHODS: The final diagnosis of patients suspected to have AID was evaluated against gene polymorphisms known to be responsible for AID, clinical manifestations, and fever pattern, in our institute from 2005 to 2016. Genomic DNA was isolated from patients' peripheral blood, and polymerase chain reaction was used to amplify the indicated exons of 12 genes: MEFV, TNFRSF1A, MVK, NLRP3, NOD2, LI1RN, IL36RN, PSMB8, NALP12, PSTPIP1, TNFAIP3, and NLRC4. Genetic polymorphisms of the above genes were examined. RESULTS: All 210 individuals (135 pediatric onset and 75 adult onset) were classified into the following 3 subgroups: (1) periodic fever (n = 74 and 25 for pediatric and adult onset, respectively), (2) recurrent fever lacking a regular period (n = 47 and 41), and (3) persistent fever (n = 14 and 9). Diagnosis of AID was highest in subgroup 1 (70.2% and 36.0% for pediatric and adult onset, respectively), followed by subgroup 2(29.8% and 17.1%), including PFAPA (periodic fever, aphthous stomatitis, pharyngitis, and adenitis) (n = 34 and 1), familial Mediterranean fever (n = 22 and 13), cryopyrin-associated periodic syndrome (n = 6 and 1), and tumor necrosis factor receptor-associated periodic syndrome (n = 3 and 1 for pediatric and adult onset, respectively). None were diagnosed with AID in subgroup 3. CONCLUSIONS: Autoinflammatory disease was more likely to be diagnosed in pediatric-onset patients compared with adult-onset patients. In both age-onset groups, AID was primarily identified in patients with periodic fever and never diagnosed in patients with persistent fever. Our findings indicate that fever pattern is a useful factor to estimate the probability of AID.

Effect of Adalimumab on Refractory Arthritis in Juvenile Idiopathic Inflammatory Myopathy with Anti-MDA5 Autoantibody.

A 10-year-old girl manifested persistent fever, skin rash, leg pain, fatigue, and joint pain. Based on muscle weakness, elevated muscle-derived enzymes, magnetic resonance imaging, and skin biopsy results, the diagnosis was juvenile idiopathic inflammatory myopathies (JIIM). Chest CT was normal; the anti-melanoma differentiation-associated protein-5 (anti-MDA5) autoantibody was positive. Initial manifestations subsided after prednisolone (PSL) and methotrexate treatment. After the PSL dosage was decreased, the patient presented with metacarpophalangeal (MCP) joint pain and swelling in both index fingers, synovial fluid, and signals on power Doppler ultrasound. The arthritis was refractory to cyclosporine and tacrolimus. Radiography showed progressive MCP joint space narrowing and joint erosion. Adalimumab was initiated 14 months after disease onset. There was a mildly increased matrix metalloproteinase-3 (MMP3) level, an erythrocyte sedimentation ratio (ESR), and a normal CRP level. Adalimumab resulted in decreased MCP joint pain and swelling. PSL was discontinued 10 months after adalimumab initiation; after 9 more months of adalimumab, there were no significant ultrasonography findings. MMP3 and ESR levels normalized during treatment. Radiography after 2 years of adalimumab showed further progressive MCP joint space narrowing restricting dorsiflexion. This report clarified that anti-MDA5-positive JIIM joint manifestations were due to active synovitis and that adalimumab is required for severe cases. Further experience is needed to determine the pathology, severity, and prognosis of this type of arthritis.