Molecular Characterization and Differentiation of Mesenchymal Progenitor Cells from Human Rheumatoid Arthritis Cartilage.

The presence of mesenchymal progenitor cells (MPCs) in rheumatoid arthritis (RA) articular cartilage is sparsely investigated largely owing to the persistent pathogenic disease condition and lack of specific biomarkers. Considering the recent advancements for potential cell-based therapies in immunomodulatory diseases, such as RA, this in vitro study was aimed at investigating the cellular, molecular, and differentiation characteristics of human RA cartilage-derived MPCs. Articular cartilage fragments from RA patients were obtained for the isolation of MPCs and characterization of their cellular and biological properties, cytogenetic stability, pluripotency, and plasticity. Established MPCs were phenotypically identified using a panel of markers, and their differentiation ability into mesenchymal lineages was assessed by cytochemical staining and the expression of molecular markers. MPCs displayed a heterogenous population of cells with characteristic features of multipotent stem cells. Cells had higher viability, proliferative rate, and colony-forming ability. Further, MPCs showed the expression of pluripotency markers, cytogenetic stability, and minimal replicative senescence. In addition, MPCs differentiated into osteocytes, adipocytes, and chondrocytes, and modulated the expression of each lineage-specific gene markers. The results demonstrated the availability of a viable pool of MPCs residing in RA cartilage, which could serve as an ideal cell source for reinstating native homotypic cartilage.

Management of Critical Coarctation of Aorta in a Premature Neonate With Low Birth Weight.

Premature neonates with low birth weight have always posed a huge management dilemma, even for teams with great expertise. In this case report, we discuss a premature neonate born with extremely low birth weight diagnosed with critical coarctation of aorta and the challenges faced in stabilizing the neonate. As per our literature review, this is the smallest neonate, weighing only 680 g, to have undergone successful repair of coarctation of aorta through posterolateral thoracotomy. Identifying the ideal timing for surgery in premature neonates with low birth weight is most crucial to minimize morbidity and mortality.

Reliability of intra-operative frozen section study in revision of infected hip arthroplasty.

INTRODUCTION: Frozen sections are extensively used to help in the diagnosis of periprosthetic joint infection during revision hip arthroplasty, though there are insufficient data in relation to its usefulness. METHODS: Twenty-one patients with infected hip arthroplasties were operated in the form of one or two-staged revision hip arthroplasties. A frozen section was obtained intra-operatively and > 5 PMN's/ HPF was considered as a positive indicator of infection. If the frozen section was reported negative (≤5 PMN's/HPF), the revision prosthesis was implanted after a thorough debridement and a wash. If the frozen section was reported as positive, post the debridement; a non-articulating antibiotic-loaded cement spacer was implanted for 8 weeks, supplemented with 3 weeks of intravenous antibiotics and 3 weeks of oral antibiotics. This was followed by an antibiotic-free interval of 2 weeks. The patient was taken up for a revision surgery once the frozen section study was negative (≤5 PMN's/HPF). The patients were followed up for a minimum of 1 year to a maximum of 2 years after the revision for any evidence of infection (assessed clinically, serologically, and radiologically). RESULTS: Frozen section analysis of PMNs per high power field had a 100% specificity in our patients in detecting periprosthetic joint infection. CONCLUSION: Frozen section study is a safe, rapid, cheap and reliable intra-operative modality to diagnose periprosthetic joint infection.

Community-associated, methicillin-susceptible, and methicillin-resistant Staphylococcus aureus bone and joint infections in children: experience from India.

Previously, the treatment of Staphylococcus aureus infections was less complex, as most of those isolated were susceptible to ß-lactam antibiotics. In recent years, there has been a marked increase in the incidence of invasive community-acquired (CA) methicillin-resistant S. aureus (MRSA) among children worldwide. However, data on the clinical characteristics and outcomes related to pediatric bone and joint infections caused by CA-S. aureus are very limited in India. In this tertiary hospital-based study, 74 patients with invasive S. aureus less than 18 years of age were identified between January 2004 and December 2008. All patients fulfilled the case definition of CA-S. aureus with evidence of infection before admission; they presented to our hospital without previous antibiotic use and were culture positive for S. aureus within 48 h of admission. All data including demographics, clinical features, treatment protocol, laboratory findings, and antimicrobial susceptibilities were recorded and compared using the SPSS 11.5 statistical software. Of the 74 patients with culture-positive S. aureus bone and joint infection, 41 had MRSA (55%). Forty-nine patients (66.2%) had osteomyelitis, of whom 29 (59.18%) had MRSA and 25 (33.7%) had septic arthritis, of whom 12 (48%) had MRSA. The MRSA group had a significantly higher erythrocyte sedimentation rate, C-reactive protein value, neutrophil count, and white blood cell count (P<0.05). The MRSA group also had longer duration of febrile days, hospital stay, and antibiotic course compared with the methicillin-susceptible S. aureus (MSSA) group (P<0.05). A clinical predictive algorithm was developed using seven significant independent multivariate predictors, with the probability of MRSA being 94% if all seven predictors were positive and 9% if five predictors were positive. Resistance to many classes of antibiotics was noted among S. aureus isolates including trimethoprim-sulfamethoxazole (MRSA 80%, MSSA 24%), erythromycin (MRSA 83%, MSSA 67%), clindamycin (MRSA 54%, MSSA 34%), and ciprofloxacin (MRSA 61%, MSSA 48%). No vancomycin resistance was observed. The morbidity associated with MRSA bone and joint infection in children is significantly higher than that caused by MSSA. Early diagnosis at the primary healthcare level and treatment with appropriate antistaphylococcal therapy are crucial to achieve optimal clinical outcomes. High levels of antimicrobial resistance of both MSSA and MRSA isolates to several classes of antibiotics are a major concern warranting the need for antimicrobial stewardship and ongoing surveillance.