Risk factors for prolonged hospitalization and disease course in osteomyelitis: a single-centre cohort study

To investigate pathogen epidemiology and clinical characteristics in osteomyelitis patients for optimizing clinical management strategies.

Confirmed osteomyelitis cases required pathogen isolation with radiological correlation. The cohort included both confirmed (culture-positive) and probable (culture-negative but meeting clinical and radiological criteria) cases, Radiation-induced osteomyelitis, sclerosing osteomyelitis and drug-associated osteomyelitis. Clinical specimens underwent standardized culture and VITEK Compact II or MALDI-TOF MS identification. SPSS 22.0 analyzed data via Mann-Whitney U tests and logistic regression for prolonged outcomes.

Analysis of 704 osteomyelitis patients revealed a male predominance (2.5:1 ratio) with median age at presentation of 41.4 years (IQR 27.0-55.0). Mortality was low (0.7%), but disability/amputation occurred in 3.53%. Patients experienced median cumulative hospitalization of 22 days (IQR 15.0-38.2) and disease duration of 4.7 months (IQR 1.5-13.6), with 79.7% undergoing surgical intervention (primarily lesion resection [22.7%] or debridement [14.2%]). The tibia was the most frequent infection site (31.5%), followed by femur (18.4%) and Jawbone (9.7%). Fracture-related infections predominated pathogenetically (47.7%), showing tibial (47.3%) and femoral (23.8%) predominance with Staphylococcus aureus (50.4%) as the leading pathogen. Microbiological confirmation was achieved in 61.9% (439/704) of cases, yielding 546 isolates. S.aureus predominated (50.8%), with 35.4% being MRSA (all susceptible to vancomycin/linezolid/tigecycline). Fracture-related infection (OR 2.24, p<0.001), femur involvement (OR 3.09, p<0.001), tibia involvement (OR 2.53, p<0.001), pathogen-positive culture (OR 3.56, p<0.001), MRSA (OR 2.64, p<0.001), and polymicrobial infection (OR 2.62, p<0.001) as significant predictors of prolonged hospitalization (>30 days). For prolonged clinical disease course (>6weeks), significant predictors included fracture-related infection (OR 1.83, p<0.001), femur involvement (OR 1.93, p=0.003), pathogen-positive culture (OR 2.66, p<0.001), S. aureus isolation (OR 1.79, p=0.001).

In conclusion, fracture, femur involvement, S. aureus, and positive pathogen culture predict prolonged osteomyelitis hospitalization and disease course, jaw and finger bone sites predict shorter hospitalization. Pathogen epidemiology and infection site dictate clinical management strategies.