The Clinical Significance of Epitrochlear Lymphadenopathy on Elbow Radiographs in Rheumatoid Arthritis

Kwon, Bae Ju; Joo, Kyung Bin; Lee, Hak Soo; Song, Ho Taek; Park, Dong Woo; Lee, Seung Ro; Hahm, Chang Kok

Abstract

PURPOSE: To evaluate the radiographic findings of epitrochlear lymphadenopathy with regard to the distribution and severity of the disease and clinal parameters in patients with rheumatoid arthritis.
MATERIALS AND METHODS
Forty six patients with rheumatoid arthritis in whom epitrochlear oval-shaped densi-ties were seen on radiographs were involved in this study. There were 14 cases of unilateral epitrochlear lym-phadenopathy in which bilateral arthritic evidence was revealed by radiographs (mixed group), and 32 of bilat-eral lymphadenopathy in which there was arthritic evidence (positive group). Twenty-three patients in whom lymphadenopathy was not seen on radiographs of the elbow and who were diagnosed as suffering from rheumatoid arthritis functioned as controls (negative group). For scoring the degree of arthritis using the sim-plified scoring method proposed by Kaye et al., joints were divided into six groups, as follows: Joint 1, elbow; Joint 2, wrist; Joint 3, radial (1st and 2nd) PIP and MCP; Joint 4, ulnar (3rd, 4th, 5th) PIP and MCP; Joint 5, Joints 1+2+3+4; Joint 6, Joints 1+4. For each joint, scores were compared with those on the contralateral side in the mixed group. Differences in clinical parameters (disease duration, rheumatoid factor, ESR, and CRP), and scores for each joint in each arm were statistically compared between be positive and negative group. The number, mean diameter, and maximal diameter of epitrochlear lymph nodes were calculated and correlated with clinical parameters and scores for each joint. To evaluate the incidence of epitrochlear lym-phadenopathy without radiographic evidence of arthritis in 46 patients (78 arms) with lymphadenopathy, the frequency of cases in which the score for the joint was zero was assessed.
RESULTS
In the mixed group, the mean score for Joint 6 of the arm with epitrochlear lymphadenopathy was significantly higher than that for the contralateral side in the mixed group (p = 0.022). Only CRP was signifi-cantly higher in the positive group than in the negative (p = 0.02). At joints 1, 2, 3, 5 and 6 of the left arm, and at joints 1, 4, 5 and 6 of the right arm, the mean score for each joint was significantly higher in the positive group than in the negative. Among 78 arms in which radiographs revealed epitrochlear lymphadenopathy, the score was zero for all joints in nine cases (11.6%).
CONCLUSION
In patients with rheumatoid arthritis, evidence of epitrochlear lymphadenopathy, as seen on radi-ographs of the elbow, appears to be related to the distribution and severity of the disease and to CRP levels.