Assessment Tools for Pulmonary Involvement in Patients with Ankylosing Spondylitis: Is Diaphragmatic Ultrasonography Correlated to Spirometry?

Objective: Spondyloarthritis (SpA) is a chronic inflammatory rheumatic disease that can lead to spinal ankylosis and consequently, restrictive pulmonary dysfunction. Thus, the present study aimed to assess the accuracy of diaphragm ultrasound compared to spirometry in the screening of restrictive pulmonary disorders in radiographic SpA patients. Methods: We conducted a cross-sectional study of 50 patients with radiographic SpA, over six months. Sociodemographic data, clinical characteristics of the disease, as well as biological, radiological, and therapeutic data, were collected. Spirometry and diaphragm ultrasound were performed. Results: The mean age of the study participants (N= 50) was 42.7±11 years [range: 25-66] with male predominance (N= 41). Spirometry showed a restrictive disorder in 32% of cases. The mean chest expansion (CE) value was 3.9±1.81cm [range: 1-9] with a median of 4 cm. A pathological value (<5cm) was observed in 72% of cases. A significant positive correlation was found between the right inspiratory diaphragmatic thickness and forced vital capacity (FVC) (r= 0.36; p = 0.02) and the supine FVC (r=0.29; p = 0.04). The left inspiratory diaphragmatic thickness was correlated with the percentage of the FVC decrease (r= 0.35; p = 0.01) defined as the percentage of difference between FVC and supine FVC. The right expiratory diaphragmatic thickness was associated with the FVC (r=0.32; p = 0.02). A significant positive correlation was found between the CE and the presence of B lines (r=0.32; p = 0.02), but not between the CE and the FVC. Conclusion: The present study showed that diaphragm ultrasonography is correlated with spirometric findings in radiographic SpA patients. Further studies are required to assess its reliability, specificity, and sensitivity in this pathology.

Factors associated with hip involvement in spondyloarthritis: a retrospective study.

BACKGROUND: Hip involvement is a life-changing event during spondyloarthritis (SpA) since it's responsible for significant disability and functional impairment. This study aimed to determine the factors associated with hip involvement in patients with SpA. METHODS: This was a retrospective study, including patients with axial and/or peripheral SpA divided into two groups: patients without and with hip involvement. Hip involvement was defined as pain or abnormality on clinical examination of the hip and/or on imaging. We collected clinical and laboratory data, activity and functional scores, and radiographic parameters. We conducted a multivariate analysis to identify the associated factors of hip involvement. RESULTS: We included 165 patients with a mean age of 46.13 ± 13.07 years, 121 patients were male. The mean duration of disease was 10.91 ± 6.94 years. Hip involvement, defined as SpA-related hip pain, joint limitation, and dysfunction and/or imaging involvement (X-ray/MRI), was noted in 60 cases (36.4%). Multivariate analysis indicated that disease duration over 10 years (OR=3.847, 95% confidence interval (CI95%)[1.324-11.178], p=0.013), radiographic sacroiliitis (OR=8.949, CI95%[1.261-63.513], p=0.028), very high disease activity (Ankylosing Spondylitis Disease Activity Score: ASDASCRP≥3,5) (OR=9.364, CI95%[2.552-34.352], p=0.001), higher Bath Ankylosing Spondylitis Functional Index (BASFI) (OR=1.439, CI95%[1.120-1.850], p=0.004) and higher Bath Ankylosing Spondylitis Metrology Index (BASMI) (OR=1.311, CI95%[1.065-1.615], p=0.011) were independently associated with hip involvement in these patients. Regarding extra-articular features, we found that pulmonary involvement and osteoporosis were significantly more frequent in patients with hip involvement, but neither retained significance in multivariate analysis. CONCLUSION: Disease duration over 10 years, radiographic sacroiliitis, very high disease activity, functional impairment, and limited spine mobility were potential associated factors with hip involvement. Patients with these factors should be closely monitored to detect hip involvement at an early stage.

Latent tuberculosis infection screening prior to biological treatment in Tunisian patients.

OBJECTIVES: The screening of latent tuberculosis infection (LTBI) is necessary to prevent infection in patients with chronic inflammatory disease (CID) undergoing biological treatment. We aimed to assess the efficacy of LTBI screening prior to biological treatment in Tunisia, considered as a high-incidence area of active TB disease. METHODS: We conducted a retrospective study over a period of 8 years [2007-2014] including patients with chronic inflammatory rheumatism receiving biologic agents since at least 6 months. The screening of LTBI was performed according to national Tunisian guidelines. RESULTS: There were 35 men and 78 women. The mean age was 47.67±13.50 years. Rheumatoid arthritis (70.8%) was the most common cause of CID. The diagnosis of LTBI was established in 23 cases. Among these 23 patients, 12 patients had negative tuberculin skin test (TST) associated with positive QuantiFERON-TB Gold (QFT-G), 10 had TST more than 10mm, one patient had a TST between 5 and 10mm associated with positive QFT-G and one patient had a history of tuberculosis inadequately treated. Preventive anti-tuberculous therapy was prescribed before biological therapy initiation in cases of LTBI. During the follow-up period (3.91 years), no case of tuberculosis reactivation has been reported among patients diagnosed with LTBI. However, 2 cases of active pulmonary tuberculosis were reported in patients with initially negative TST and QFT-G. CONCLUSION: Our study showed that the Tunisian recommendations allowed detecting a LTBI in 20% of biologic therapy candidates. Preventive measures including screening of LTBI and eventually a prophylactic treatment improve the safety of biological treatments.