Efficacy of MRP8/14 as a Marker of Disease Activity in Rheumatoid Arthritis

Objective: Early and accurate evaluation of the presence and activity of synovitis is extremely important in the diagnosis and treatment of rheumatoid arthritis. Myeloid related protein 8/14 (MRP8/14), also known as calprotectin or S100A8/A9 is considered as a sensitive marker for local inflammatory activity in rheumatoid arthritis. The aim of this study is to demonstrate the efficacy of MRP8/14 as a marker of disease activity in RA. Methods: Thirty-one patients with diagnosis of RA who received treatment without biological drugs at our institution were included in this study. Serum MRP8/14, CRP and MMP-3 were tested in all patients. Disease activity was evaluated using DAS28-CRP and SDAI. Ultrasonography was performed on the wrists and MCP joints of both hands using semi-quantitative scale of power Doppler signal. The sum of scales in joints was calculated as the PD score. The correlation of MRP8/14 with serum biomarkers, disease activity and ultrasonography examination was investigated. Result: Serum MRP8/14 was strongly correlated with CRP (r = 0.63) and MMP-3 (r = 0.69). A correlation was observed between serum MRP8/14 and DAS28-CRP (r = 0.53) and SDAI (r = 0.66). No significant correlation was found between PD scores and MRP8/14. Conclusion: This study demonstrated that MRP8/14 is correlated with evaluated disease activity and markers of serum inflammatory response in patients not using biological drugs. MRP8/14 is considered an effective new method for objective evaluation of synovitis in RA.

Anaphylactic Reaction to a Change in the Route of Administration of Abatacept: A Case Study

The incidence of anaphylactic reaction after the long-term use of abatacept has not been reported until now. Herein, we present a case of rheumatoid arthritis (RA) in which the patient experienced an anaphylactic reaction one year after initiation of treatment with abatacept. A 75-year-old woman visited our hospital with symptoms of bilateral knee pain and swelling. She was initially treated with methotrexate (6 mg/week increased to 8 mg/week). Two months later, because of inadequate response, self-injections of abatacept (subcutaneous;125 mg every two weeks) were prescribed. However, 6 months later, because of frequent stomatitis, the methotrexate dose was decreased to 6 mg/week, which resulted in worsening of RA. We changed the route of abatacept administration from subcutaneous injection to intravenous infusion (500 mg/month as a drip). After 30 min of starting the drip, the patient experienced itchiness and drop in vital signs, which were managed using methylprednisolone (2 doses, 125 mg each), dopamine hydrochloride (8 mg/h), and oxygen therapy (flow decreased from 3 L/min to 1 L/min). Wheals and redness were treated with oral antihistamines. Six hours after the onset of the anaphylactic reaction, the vital signs were stabilized. On the subsequent day, the patient’s general state was confirmed to be normal. One month later, etanercept (25 mg) treatment was initiated. The patient is currently in remission. We recommend caution when changing the route of administration and dosage of abatacept in anti-cyclic citrullinated peptide antibody-positive patients or those with a history of mild infusion-related reaction.

Function Assessment for Rheumatoid Thumb Deformity

Objective: Nalebuff’s type I deformity of the rheumatoid thumb, which is the most common thumb deformity with rheumatoid arthritis, can be classified into three stages according to the range of motion of the thumb. However, a functional assessment for each stage has never been undertaken. Methods: The ranges of motion of the thumb metacarpophalangeal and interphalangeal joints were evaluated to determine Nalebuff’s clinical stage, and both the Modified Kapandji Index (MKI) and the simple test for evaluating hand function (STEF) were used to evaluate hand function in 32 rheumatoid arthritis patients with type I deformity. We assessed hand function in each stage, and examined the relationship between the three clinical stages and dysfunction of the hand. Results: The scores for both MKI and STEF were significantly reduced in parallel with advancing stage of thumb deformity. Conclusion: Nalebuff’s staging system is also useful for reflecting the level of thumb function.

Establishing a Calculation Method for Estimating the Normal Circumference of the Proximal Interphalangeal Finger Joints

Objective: To estimate the normal circumference of the interphalangeal (IP) thumb joint and the proximal IP (PIP) joints from the index finger to the little finger using individual physical parameters such as body height and body weight. Methods: The maximum size on the ring gauge was recorded which caused resistance when the IP joint of the thumb or PIP joints of the index to small fingers were passed through the gauge. RG was defined as the ring gauge number with the same diameter as the circumference of the IP thumb joint and PIP finger joints from the index finger to the little finger. There were 300 healthy subjects and 600 hands. Univariate and multivariate analyses were used to analyze the relationships between RG and the parameters of age, sex, height, weight, and dominant hand, and regression equations were derived. Results: Age, sex and body weight were all statistically significant predictive factors of RG in all fingers. R2, the coefficient of determination in the regression equation, was almost 0.7 for all fingers, indicating that a moderate or strong correlation was observed between RG and the regression equation. Conclusions: The circumference of the IP thumb joint and PIP finger joints from the index finger to the little finger can be estimated in healthy individuals using a calculation formula that takes age, sex, body height and body weight into account.