Analysis of the clinical characteristics of osteomyelitis in infants aged under 6 months.

This study aimed to summarize the clinical characteristics and prognosis of osteomyelitis in infants under 6 months of age. A retrospective analysis was conducted on the clinical data of 24 infants under 6 months of age diagnosed and treated for osteomyelitis between November 2017 and October 2024. This was a single-center study. General information, clinical manifestations, laboratory tests, treatments, and prognosis were summarized. Twenty-four infants (13 boys, 11 girls; age 0.5-5.6 months) were included. All presented with limb swelling, reduced movement, or pain on passive movement. Fever was initially present in 7 cases and developed early in 21 (87.5%). The femur (11/29, 37.9%) and tibia (7/29, 24.1%) were the most common infection sites. At admission, elevated WBC, C-reactive protein, and erythrocyte sedimentation rate were observed in 23 (95.8%), 22 (91.7%), and 19 (79.2%) infants, respectively. Staphylococcus aureus was the predominant pathogen (14/24, 58.3%). All received empirical antibiotics, adjusted based on culture results. Twenty underwent cortical window drainage. Follow-up of 21 infants (6 months to 8.5 years) revealed 1 case each of limb shortening, genu valgum, and restricted joint movement; the remaining 18 had normal limb function. Patients were stratified by prognosis for comparison. No significant differences were found in any variables between the 2 groups. Osteomyelitis in infants under 6 months of age lacks specific early clinical manifestations. Prompt laboratory and imaging evaluations are critical for early diagnosis and treatment. Overall, the prognosis is favorable.