AB1087 THE RELATIONSHIP BETWEEN FEMORAL CARTILAGE THICKNESS AND AMYLOIDOSIS IN PATIENTS WITH FAMILIAL MEDITERRANEAN FEVER: PRELIMINARY STUDY
Authors: Halise Hande Gezer, Didem Erdem, Sevtap Acer Kasman, Hatice Sule Baklacioglu, Mehmet Tuncay Duruöz
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Familial Mediterranean fever (FMF) is the most common hereditary inflammatory disease characterized by recurrent attacks of fever and serositis. The most devastating complication of FMF is amyloidosis, leading to chronic renal failure (CRF). The amyloid protein may accumulate in many tissues including the cartilage, particularly in the kidneys. Sonographic femoral cartilage thicknesses (FCT) was evaluated in many chronic rheumatic diseases and was shown to be thinner than healthy individuals. <h3>Objectives</h3> The aim of this study was to determine FCT in FMF patients and healthy individuals and to assess the relationship of FCT with the development of amyloidosis and clinical features. <h3>Methods</h3> Patients diagnosed with FMF according to the Tel-Hashomer criteria were included in the study. Patients with trauma and other inflammatory disease and patients with a history of knee operation were excluded. Femoral cartilage thickness of both knees was measured with a 7-12 MHz linear probe in maximum knee flexion. Three mid-point measurement were obtained from each knees: lateral femoral condyle (LFC), intercondylar area (ICA) and medial femoral condyle (MFC). Clinic characteristics of the patients including disease duration, medications, comorbid conditions, amyloidosis, CRF, FMF gene mutation, arthritis, sacroiliitis, PRAS score and physical activity scores were recorded. Descriptive analysis was performed for all parameters. The Mann-Whitney U-test and Spearman's correlation coefficient were used in statistical analysis. P&lt;0.05 was considered statistically significant. <h3>Results</h3> A total of 45 patients with FMF (35 women, 10 men) and 20 age-sex-BMI matched controls (14 women, 6 men) were enrolled in this study. The mean age of the patients and controls were 38.2 (SD:12.2) and 37.5 (SD:8.5) years, respectivelly. Amyloidosis occurred in 7 patients (15.6%), CRF in 3 (6.7%), sacroilitis in 10 (22.2%) and arthritis in 16 (35.6%). Disease activity was mild in 48.9%, moderate in 20% and severe 22.2% of the patients. The mean FCT in centimeters values in the FMF and control groups were as follows: on the right side LFC 0.19 (SD:0.03) and 0.22 (SD:0.05), ICA 0.23 (SD:0.05) and 0.24 (SD:0.06), MFC 0.20 (SD:0.04) and 0.24 (SD:0.06); on the left side LFC 0.19 (SD:0.03) and 0.21 (SD:0.03), ICA 0.22 (SD:0.05) and 0.24 (SD:0.06), MFC 0.19 (SD:0.03) and 0.22 (SD:0.04). Patients with FMF had decreased cartilage thickness at the lateral condyle of both knees (p&lt;0.05) and medial condyle of the left knee (p&lt;0.05) compared with controls. FCT measurements were similar in patients with or without arthritis, sacroiliitis, amyloidosis and CRF. Physical activity scores were significantly correlated with the left LFC (r=0.309). Total protein in 24-hour urine showed a highly negative correlation with left LFC (r=-0.718). <h3>Conclusion</h3> These findings suggest that patients with FMF have decreased FCT compared with controls. There is no significant relationship between the FCT and amyloidosis, it has significant relation with proteinuria level. <h3>References</h3> [1] Ozcakar, L., et al., Femoral cartilage thickness measurements in healthy individuals: learning, practicing and publishing with TURK-MUSCULUS. J Back Musculoskelet Rehabil, 2014. 27: p. 117-24. [2] Mitrovic, D.R., et al., Amyloid deposits in human knee and hip joints. J Rheumatology International. 1985. 5(2): p. 83-89. <h3>Disclosure of Interests</h3> Halise Hande Gezer: None declared, Didem Erdem: None declared, Sevtap Acer Kasman: None declared, Hatice Sule Baklacioglu: None declared, Mehmet Tuncay Duruöz Grant/research support from: Abvie, Speakers bureau: Novartis, AMGEN, Abdi İbrahim, İlko