Beyond the Liver: A Unique Case of Pyogenic Liver Abscess Caused by Peptostreptococcus micros Penetrating the Chest Wall.

Liver abscesses are uncommon pyogenic infections with diverse microbiology, often involving enteric gram-negative bacilli such as Escherichia coli and Klebsiella pneumoniae. Standard management includes antibiotic therapy and abscess drainage. We present a case of a 37-year-old male with chronic right upper quadrant abdominal pain, who was found to have an enlarging liver mass infiltrating the chest wall and right-side chest ribs, ultimately diagnosed as a large pyogenic liver abscess (PLA) extending into the chest wall. Notably, the abscess was attributed to Peptostreptococcus micros, a rarely isolated pathogen in liver abscesses. Despite initial unsuccessful percutaneous drainage, surgical intervention proved necessary for definitive treatment. This case underscores the diagnostic challenge posed by uncommon pathogens in liver abscesses and emphasizes the effectiveness of surgical drainage in managing refractory cases.