Machine learning identification of thresholds to discriminate osteoarthritis and rheumatoid arthritis synovial inflammation

Background We sought to identify features that distinguish osteoarthritis (OA) and rheumatoid arthritis (RA) hematoxylin and eosin (H&E)-stained synovial tissue samples. Methods We compared fourteen pathologist-scored histology features and computer vision-quantified cell density (147 OA and 60 RA patients) in H&E-stained synovial tissue samples from total knee replacement (TKR) explants. A random forest model was trained using disease state (OA vs RA) as a classifier and histology features and/or computer vision-quantified cell density as inputs. Results Synovium from OA patients had increased mast cells and fibrosis (p < 0.001), while synovium from RA patients exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, binucleate plasma cells, sub-lining giant cells, fibrin (all p < 0.001), Russell bodies (p = 0.019), and synovial lining giant cells (p = 0.003). Fourteen pathologist-scored features allowed for discrimination between OA and RA, producing a micro-averaged area under the receiver operating curve (micro-AUC) of 0.85±0.06. This discriminatory ability was comparable to that of computer vision cell density alone (micro-AUC = 0.87±0.04). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (micro-AUC = 0.92±0.06). The optimal cell density threshold to distinguish OA from RA synovium was 3400 cells/mm2, which yielded a sensitivity of 0.82 and specificity of 0.82. Conclusions H&E-stained images of TKR explant synovium can be correctly classified as OA or RA in 82% of samples. Cell density greater than 3400 cells/mm2 and the presence of mast cells and fibrosis are the most important features for making this distinction

Clinical Use of Improved Diagnostic Testing for Detection of Prion Disease

Prion diseases are difficult to recognize as many symptoms are shared among other neurologic pathologies and the full spectra of symptoms usually do not appear until late in the disease course. Additionally, many commonly used laboratory markers are non-specific to prion disease. The recent introduction of second-generation real time quaking induced conversion (RT-QuIC) has revolutionized pre-mortem diagnosis of prion disease due to its extremely high sensitivity and specificity. However, RT-QuIC does not provide prognostic data and has decreased diagnostic accuracy in some rarer, atypical prion diseases. The objective of this review is to provide an overview of the current clinical utility of fluid-based biomarkers, neurodiagnostic testing, and brain imaging in the diagnosis of prion disease and to suggest guidelines for their clinical use, with a focus on rarer prion diseases with atypical features. Recent advancements in laboratory-based testing and imaging criteria have shown improved diagnostic accuracy and prognostic potential in prion disease, but because these diagnostic tests are not sensitive in some prion disease subtypes and diagnostic test sensitivities are unknown in the event that CWD transmits to humans, it is important to continue investigations into the clinical utility of various testing modalities

Possible bupivacaine toxicity after intraarticular injection for postarthroscopic analgesia of the knee: implications of the surgical procedure

We report a case of possible bupivacaine toxicity after intraarticular injection during knee arthroscopy. The importance of the specific type of surgical procedure performed during arthroscopy and its relationship to potential local anesthetic toxicity are highlighted

Perioperative Complications in Patients With Inflammatory Arthropathy Undergoing Total Hip Arthroplasty

Limited information exists comparing the short-term complications of the different inflammatory arthropathies (IAs) after total hip arthroplasty (THA). Our objectives were to (1) compare perioperative complications and (2) determine the most common complications between the different IA subtypes compared with patients with osteoarthritis (OA) undergoing primary THA. The Nationwide Inpatient Sample was used to identify 2,102,238 patients undergoing elective, unilateral THA between 2002 and 2011. Of these, 86,671 (4%) had an IA, including rheumatoid arthritis (RA), psoriatic arthritis, juvenile idiopathic arthritis (JIA), ankylosing spondylitis (AS), and systemic lupus erythematosus (SLE). Preoperative diagnosis, comorbidities, and postoperative complications were determined using International Classification of Disease Clinical Modification version 9 codes. The prevalence of in-hospital medical and orthopedic complications was compared between patients with an IA and OA. When compared with patients with OA, patients with RA, JIA, SLE, and AS had significantly more inpatient medical and orthopedic complications immediately after THA (P < .01). Patients with JIA had the highest orthopedic complication rate (2.8%). Specific orthopedic complications by subtype included wound dehiscence for RA and AS periprosthetic fractures for JIA and increased mortality for SLE patients. There were no significant differences in medical or orthopedic complications seen in patients with psoriatic arthritis. Differences exist in postoperative inpatient medical and orthopedic complications among patients with different types of IAs after THA. Our results point out the importance of preoperative optimization in patients with IA and monitoring for selective postoperative complications

Perioperative Complications in Patients with Inflammatory Arthropathy Undergoing Total Knee Arthroplasty

Little data exists comparing acute post-operative outcomes in patients with different types of inflammatory arthritis (IA) after undergoing a total knee arthroplasty (TKA). Our objectives were to compare perioperative complications and determine the most common complications between the different IA subtypes compared with patients with osteoarthritis undergoing primary TKA. We found significant differences when comparing complications within the different subtypes of IA. RA patients, despite having a greater number of comorbidities had a reduced rate of medical complications postoperatively compared to the OA cohort. All of the inflammatory subtypes had a higher rate of orthopedic complications postoperatively compared to the OA group except for patients with AS. However, ankylosing spondylitis had the highest mortality rate as well as medical complication rate among the subtypes

Total Knee Arthroplasty in Patients With Juvenile Idiopathic Arthritis

BackgroundTotal knee arthroplasty (TKA) for juvenile idiopathic arthritis is rare but is nonetheless indicated for many patients with this disease. Few reports exist on the results of TKA in patients with juvenile idiopathic arthritis.Questions/purposesIt was sought to determine (1) survivorship and (2) functional outcomes of TKAs in patients with juvenile idiopathic arthritis.MethodsResults were combined from patients treated by experienced surgeons at five hospitals between 1979 and 2011. Two hundred nineteen patients (349 TKAs) were identified and contacted to survey their outcomes at a minimum followup of 2 years (mean, 12 ± 8 years; range, 2-33 years). The average age at surgery was 28.9 ± 9.7 years (range, 11-58 years). Data on revision surgery and ability to perform daily activities were collected.ResultsThe 10-year survivorship was 95%, decreasing to 82% by 20 years. At latest followup, 31 of 349 TKAs (8.9%) had been revised for either polyethylene failure or loosening (18 TKAs), infection (four), stiffness (three), periprosthetic fractures (two), bilateral amputation for vascular reasons (two), patellar resurfacing (one), and instability (one). Walking tolerance was unlimited in 49%, five to 10 blocks in 23%, and less than five blocks in 28%. Eleven percent could not manage stairs, and another 59% depended on railings. A cane was used by 12% and crutches by 7%; 12% were wheelchair-dependent.ConclusionsTKA survivorship in patients with juvenile idiopathic arthritis was inferior to that typically seen in younger patients with osteoarthritis or even rheumatoid arthritis confirming results of earlier studies with smaller patient numbers. This is especially disconcerting because younger patients require better durability of their TKAs

Total Knee Arthroplasty in Patients With Juvenile Idiopathic Arthritis

BACKGROUND: Total knee arthroplasty (TKA) for juvenile idiopathic arthritis is rare but is nonetheless indicated for many patients with this disease. Few reports exist on the results of TKA in patients with juvenile idiopathic arthritis. QUESTIONS/PURPOSES: It was sought to determine (1) survivorship and (2) functional outcomes of TKAs in patients with juvenile idiopathic arthritis. METHODS: Results were combined from patients treated by experienced surgeons at five hospitals between 1979 and 2011. Two hundred nineteen patients (349 TKAs) were identified and contacted to survey their outcomes at a minimum followup of 2 years (mean, 12 ± 8 years; range, 2–33 years). The average age at surgery was 28.9 ± 9.7 years (range, 11–58 years). Data on revision surgery and ability to perform daily activities were collected. RESULTS: The 10-year survivorship was 95%, decreasing to 82% by 20 years. At latest followup, 31 of 349 TKAs (8.9%) had been revised for either polyethylene failure or loosening (18 TKAs), infection (four), stiffness (three), periprosthetic fractures (two), bilateral amputation for vascular reasons (two), patellar resurfacing (one), and instability (one). Walking tolerance was unlimited in 49%, five to 10 blocks in 23%, and less than five blocks in 28%. Eleven percent could not manage stairs, and another 59% depended on railings. A cane was used by 12% and crutches by 7%; 12% were wheelchair-dependent. CONCLUSIONS: TKA survivorship in patients with juvenile idiopathic arthritis was inferior to that typically seen in younger patients with osteoarthritis or even rheumatoid arthritis confirming results of earlier studies with smaller patient numbers. This is especially disconcerting because younger patients require better durability of their TKAs. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence