As the population ages and demand for total joint arthroplasty increases, rates of periprosthetic joint infection are expected to increase in the geriatric population. Studies comparing prevalence of risk factors, etiology, management, and mortality of prosthetic joint infection in older patients are lacking. We compared clinical characteristics, management, and mortality of patients <75 vs ≥75 years of age with first prosthetic joint infection of the hip or knee admitted to a tertiary medical center between September 2017 and December 2019. Ninety-eight patients (<75 years of age [n = 63]; ≥75 years of age (n = 35) were studied. Groups were similar in terms of etiology, culture-directed therapy, antibiotic suppression, and length of stay. There was no difference in surgical management, performed in almost 97% of cases in both groups. Arrhythmia and heart failure were more prevalent in those aged ≥75 years. Readmission related to prosthetic joint infection occurred less often in older individuals (P = .005). Deaths within 1 year of diagnosis were rare (n = 4; 4.1%), occurring in older patients and resulting mostly from sepsis. In our single-center study, patients with first prosthetic joint infection had similar management, regardless of age. We identified cardiac history as one of the host factors for prosthetic joint infection most seen in patients ≥75 years of age. Although deaths were rare, 1-year mortality was higher in patients aged ≥75. Prospective, multicenter studies are needed to explore risk factors and management strategies of prosthetic joint infection among elderly populations.

Pneumonia is the most common presentation of invasive mold infections (IMIs), and is pathogenetically characterized as angioinvasion by hyphae, resulting in tissue infarction and necrosis. Aspergillus species are the typical etiologic cause of mold pneumonia, with A. fumigatus in most cases, followed by the Mucorales species. Typical populations at risk include hematologic cancer patients on chemotherapy, bone marrow and solid organ transplant patients, and patients on immunosuppressive medications. Invasive lung disease due to molds is challenging to definitively diagnose based on clinical features and imaging findings alone, as these methods are nonspecific. Etiologic laboratory testing is limited to insensitive culture techniques, non-specific and not readily available PCR, and tissue biopsies, which are often difficult to obtain and impact on the clinical fragility of patients. Microbiologic/mycologic analysis has limited sensitivity and may not be sufficiently timely to be actionable. Due to the inadequacy of current diagnostics, clinicians should consider a combination of diagnostic modalities to prevent morbidity in patients with mold pneumonia. Diagnosis of IMIs requires improvement, and the availability of noninvasive methods such as fungal biomarkers, microbial cell-free DNA sequencing, and metabolomics-breath testing could represent a new era of timely diagnosis and early treatment of mold pneumonia.

There is no consensus on diagnostic criteria for hip and knee periprosthetic joint infections (PJIs). This study evaluated Infectious Diseases Society of America (IDSA), International Consensus Meeting 2018 (ICM2018), and European Bone and Joint Society (EBJIS) criteria, finding IDSA most accurate for early PJI and knee infections, while ICM2018 and EBJIS were superior for delayed and late cases. Diagnostic approaches should consider infection timing and context.

Background: Discrepancies exist between preoperative synovial aspirations and intraoperative cultures. It is unclear whether the results of preoperative arthrocentesis add diagnostic value for patients with possible prosthetic joint infection (PJI). Methods: We retrospectively identified adult patients treated surgically for hip and knee PJI who underwent both preoperative aspiration and intraoperative sampling. Synovial and intraoperative culture results were analyzed. Cultures were defined as concordant if they yielded the same organism(s) or if both were negative. Cultures were considered to be discordant if different organisms were isolated or if one had growth and the other was sterile. Demographic, clinical, and laboratory variables between groups were compared. Results: Among 75 patients, 54 (72 %) had concordant results, and 21 (28 %) had discordant results. In the discordant group, 7 of 21 patients (33 %) had negative synovial cultures with positive intraoperative cultures. Among culture-positive concordant patients, staphylococci and streptococci were the most common isolates, with 20 % gram negatives. True culture-negative PJI was uncommon (n=1). Preoperative antibiotic exposure was frequent (>50 %) in both groups. Conclusion: In a cohort of hip and knee PJI patients treated surgically, preoperative synovial aspiration cultures were concordant with intraoperative cultures in 72 % of cases, but negative synovial aspirations did not reliably exclude infection. Given the observed discordance, our findings support the obtainment of preoperative synovial aspiration and the collection of multiple intraoperative specimens at the time of surgery.

Aim: Discrepancies between preoperative synovial aspiration and intraoperative cultures may occur, even in the absence of antibiotic therapy. This study evaluated the concordance between preoperative synovial aspiration and intraoperative culture results in patients undergoing surgery for hip and knee prosthetic joint infection (PJI). Methods: Retrospective review of patients >18 years diagnosed with their first episode of hip or knee PJI between September 2017 and December 2020 who underwent surgical management. Demographics, microbiology (synovial aspiration and intraoperative cultures), and use of antibiotics relative to preoperative arthrocentesis and surgery were assessed. Concordance was defined as either matching organisms or negative results in both settings. Results: Among 75 patients (mean age 70.0 +/- 13.3 years, 50.7% male, 71% white/Caucasian and 95% non-Hispanic), 54 (72%) had concordant results and 21 patients (28%) were discordant. Among the concordant group, 45/54 (83%) had identical organisms isolated, most commonly methicillin-sensitive Staphylococcus aureus (MSSA). Nine (17%) had negative cultures in both settings. Only 2/9 (22%) received antibiotics before preoperative synovial aspiration, and 4/9 (44%) received preoperative antibiotics. Among discordant patients, 14/21 (67%) had positive preoperative synovial aspiration culture. 11/14 (78%) with a positive preoperative synovial had negative intraoperative culture and 9/11 (82%) had received preoperative antibiotics. 3/14 (22%) had differing organisms across samples. 7/21 (33%) had negative preoperative synovial aspiration culture and positive intraoperative cultures; none received antibiotics prior to preoperative synovial aspiration. (Table 1) Conclusions: Almost 75% of patients had concordance between synovial preoperative aspiration and intraoperative culture. Negative preoperative cultures do not exclude infection and isolation of a pathogen does not preclude polymicrobial infection. Our results support the recommendation to obtain multiple intraoperative specimens at the time of surgery. For any figures or tables, please contact the authors directly.