Bartonella can cause hepatic lesions (liver). Below are some studies along with some ideas of succcessful treatments using antimicrobials.
https://www.ncbi.nlm.nih.gov/pubmed/29850344
https://www.ncbi.nlm.nih.gov/pubmed/28580326
https://www.ncbi.nlm.nih.gov/pubmed/28795543
https://www.ncbi.nlm.nih.gov/pubmed/25610689
https://www.ncbi.nlm.nih.gov/pubmed/26780031