Intraoperative Fungal and Acid-Fast Bacilli Culture Use in Orthopedic Surgery and the Cost to the Medical System: A Narrative Review

Fungal and acid-fast bacilli (AFB) infections are uncommon but clinically important causes of surgical site infection (SSI) and periprosthetic joint infection in orthopaedic surgery. Despite their rarity, fungal and AFB cultures are frequently obtained intraoperatively, and practice patterns vary widely due to the absence of broadly accepted, standardized guidance. This narrative review descriptively summarizes the available literature on fungal and AFB culture use in orthopaedic surgery, with a focus on reported indications for intraoperative testing, diagnostic yield, and cost considerations, in order to highlight practice variation and identify areas for future study. Across studies, standardized protocols for when and how to obtain fungal and AFB cultures were uncommon, and reported culture positivity was generally low, with many positive results representing contaminants or findings of uncertain clinical significance. Routine ordering in low-risk scenarios was associated with substantial cumulative cost, including annual institutional expenditures and multi-year charges in some cohorts. Targeted, protocol-driven approaches demonstrated meaningful reductions in low-yield testing, including reports of large decreases in unnecessary cultures in appropriately sized practice settings. Routine intraoperative fungal and AFB cultures in orthopaedic surgery appear to have low diagnostic yield in many commonly tested scenarios and often do not change clinical management, raising concerns about cost-effectiveness. A selective, indication-driven strategy, such as prioritizing higher-risk hosts, specific anatomic sites, and cases with clinical suspicion for atypical infection, may preserve diagnostic value while reducing unnecessary costs. Future work should focus on developing and validating standardized testing algorithms and evaluating long-term cost-benefit outcomes of targeted versus routine culture practices.