PT - JOURNAL ARTICLE AU - Umemoto, Daichi AU - Nishioka, Hiroaki TI - Empyema caused by <em>Streptococcus dysgalactiae</em> subsp. <em>equisimilis</em> subsequently to bacteraemia AID - 10.1136/bcr-2023-258445 DP - 2024 Jan 01 TA - BMJ Case Reports PG - e258445 VI - 17 IP - 1 4099 - http://casereports.bmj.com/content/17/1/e258445.short 4100 - http://casereports.bmj.com/content/17/1/e258445.full SO - BMJ Case Reports2024 Jan 01; 17 AB - Streptococcus dysgalactiae subsp. equisimilis (SDSE) commonly causes a variety of infections in older individuals. However, respiratory infections are uncommon. We present the case of an older man with empyema due to SDSE subsequently to bacteraemia. He presented with a 1-day history of fever and laboratory findings revealed an increased white blood cell count and C- reactive protein (CRP) level. Chest CT revealed no infiltration and no pleural effusion. SDSE was detected in the blood cultures. Primary bacteraemia was suspected and antibiotic administration was initiated; however, 2 days later, his right breath sound diminished, and chest radiography revealed right pleural effusion. Thoracentesis yielded cloudy fluid with frank pus; thus, he was diagnosed with empyema due to SDSE, and a drainage tube was placed. Thereafter, his fever improved, and his CRP level decreased. Thus, SDSE can cause empyema probably by haemotological spread of SDSE to the pleura.