The Incidence, Pathogen Spectrum, and Resistance Profile of Pyogenic Spondylodiscitis: A Nationwide Retrospective...

The incidence of the spinal infection pyogenic spondylodiscitis is rising, particularly in the aging, multimorbid segment of the population. The goal of this study was to analyze nationwide trends in the epidemiology, pathogen spectrum, and antimicrobial resistance profile of this disease in Germany over the period 2005–2023.

All hospital discharges were analyzed retrospectively using nationwide German Diagnosis Related Groups (G-DRG) data. Hospitalizations with a primary ICD-10-GM diagnosis of spinal osteomyelitis, pyogenic intervertebral disc infection, or discitis, not otherwise specified (M46.2*, M46.3*, M46.4*) were included for analysis. The age-adjusted incidence was calculated using population data from the Federal Statistical Office. Pathogen determinations and resistance phenotypes were ascertained from supplementary pathogen codes.

A total of 151 544 cases were identified. Over the study period, the age-adjusted incidence doubled (from 5.41 to 10.02 cases per 100 000 persons), the patients’ mean age increased from 65.8 to 72.2 years, and the proportion of patients aged 70 years or more rose (from 42.6% to 62.3%). The mean length of hospital stay decreased, while in-hospital mortality doubled (from 3.25% to 6.79%). At the same time, the rate of pathogen determination improved. The proportion of Staphylococcus aureus fell markedly (from 34.5% to 17.2%), while other gram-positive pathogens increased. Gram-negative pathogens remained stable. Resistant S. aureus isolates became rarer, while resistant enterobacterales and enterococci were identified more frequently. There was an overall downward trend in the rate of resistant pathogens in the final 6 years of the study period (from 14.1% in 2017 to 6.9% in 2023).

In Germany, pyogenic spondylodiscitis mainly affects older patients, and the associated in-hospital mortality is rising. Changes in the pathogen spectrum and in resistance patterns indicate the need for corresponding adjustments to empirical treatment regimens.