Canine anaplasmosis is an increasingly common tick-borne disease in Pennsylvania. Due to false negatives associated with in-clinic serologic tests, additional ancillary diagnostics are needed to diagnose acute canine anaplasmosis. Between November 2015 and July 2020, 61 cases of suspect acute canine anaplasmosis were diagnosed at Metzger Animal Hospital in State College, Pennsylvania. The results of this research will summarize data on history, signalment, physical exam, laboratory, and ancillary diagnostics from cases of acute canine anaplasmosis.