A fatal outbreak of sarcoptic mange caused by Sarcoptes scabiei in San Joaquin kit foxes (Vulpes macrotis mutica) in Bakersfield, California, US is causing the once-stable population to decline. Given the fatality of the disease in this already-endangered species experiencing continued population declines, city-wide interventions are underway. To optimize medical management of mange-infested kit foxes, we documented serum biochemistry and hematology values for 11 kit foxes with mange collected from January–May 2015 and compared them to historical data from 18 healthy Bakersfield kit foxes. Results from kit foxes with mange were consistent with chronic illness and inflammation, protein loss, hypoglycemia, and dehydration. These findings contribute to our understanding of this debilitating, multisystemic disease that can progress to death in individuals without intervention and will aid in the treatment and care of rehabilitated individuals.