Periprosthetic joint infections in patients with rheumatoid arthritis are associated with higher complication and mortality rates.

INTRODUCTION: Periprosthetic joint infection (PJI) remains the most devasting complication after total joint arthroplasty (TJA). There has been a significant focus on this topic in recently-published medical literature. However, relatively little has been published about PJI in patients with rheumatoid arthritis (RA), which are often physiologically frail and immunocompromised. A better understanding of PJI in this patient population is therefore crucial. The main aims of this paper are to (1) report complication and mortality rates in a cohort of PJI-RA patients; and (2) clinically characterize them. METHODS: Medical and surgical records of all RA PJI patients treated surgically from 2003 to 2020 were retrospectively reviewed. Medical history, physical examination, reactive protein (CRP) level, procalcitonin, white blood cell (WBC) count, joint aspiration results, and cultures were used to determine PJI. RESULTS: 54PJIs, 49 of them chronic, were treated in 53RA patients. Mean patient age was 65 yrs. (range = 32-88); 33females and 20 males (one bilateral hip). The overall mortality rate was 18.9%(n = 10), with five deaths directly attributed to PJI. Staphylococci accounted for 34 infections (63%), while 11(20.4%) had multiorganism infections and six culture-negative PJI. At the end of treatment 79.6%(n = 43) still had an implanted TJR, 7.4% (n = 4) had spacers, 5.6%(n = 3) had undergone resection arthroplasty, 3.7%(n = 2) arthrodesis, and one each amputation and exarticulation. CONCLUSIONS: Mortality and specially complication rates were (are) high in this RA patients group presenting PJI. Delays to diagnosis and treatment may explain some of these poor outcomes. LEVEL OF EVIDENCE: A cohort level III retrospective study.

V-region gene analysis of locally defined synovial B and plasma cells reveals selected B cell expansion and accumulation of plasma cell clones in rheumatoid arthritis.

OBJECTIVE: To elucidate the development of synovial tissue-specific B cell immune responses, the clonality of individual naive B cells, memory B cells, and plasma cells and their organization and histologic localization in the inflamed tissue were investigated in patients with rheumatoid arthritis (RA). METHODS: B and plasma cells were isolated by laser capture microdissection (LCM) from the synovial tissue of patients with RA. In addition, single naive B cells, memory B cells, and plasma cells were sorted from synovial tissue cell suspensions. RNA was extracted from the cells, and Ig VH genes were amplified, cloned, and sequenced. RESULTS: Both LCM and single cell sorting analyses showed that naive and memory B cells infiltrated the RA synovial tissue. Comparison of the V-gene repertoire of B and plasma cells suggested that synovial plasma cells were generated, by and large, from locally activated B cells, indicating that a selected population of memory B cells differentiates into large plasma cell clones that then accumulate in the inflamed tissue. Clonally related plasma cells were isolated from separate and distinct localized areas of the tissue, suggesting that the newly generated plasma cells have a high migratory capacity. CONCLUSION: These results support the idea of a continuous activation of selected B cell clones, and hence a massive accumulation of plasma cells, in RA synovial tissue. As B cells and their secreted antibodies are an important factor in controlling inflammatory processes, patients with RA displaying intensive synovial tissue lymphocytic infiltrations might benefit from B cell depletion therapy. Early treatment will prevent accumulation of pathogenic plasma cells.

'Hip' pain.

'Hip' pain is usually located in the groin, upper thigh or buttock and is a common complaint. Slipped capital femoral epiphysis, avascular femoral head necrosis and apophyseal avulsion are the most common diagnoses in childhood and adolescents. Strains and fractures are common in sport-active adults. Osteoarthritis occurs in middle-aged and older adults. Trauma may result in femoral head fracture or typical muscle and tendon sprains and bursitis. Septic or inflammatory arthritis can occur at every age. Septic arthritis, fractures and acute epiphyseal slipping are real emergency cases. Congenital dysplasia of the hip joint may lead to labral tears and early osteoarthritis. The most important hip problems in children, adolescents, adult and older people are discussed; these problems originate from intra-articular disorders and the surrounding extra-articular soft tissues. Medical history, clinical examination and additional tests, including imaging, will be demonstrated. Principles of treatment are given for specific disorders.