Immunopathology is the laboratory study of diseases of the immune system. An immunopathologist is a pathologist with expertise in determining the causes of disease by studying cells, tissues and body fluids in the laboratory. The pathologist interprets tissue samples under a microscope, and aids the physician in diagnosing, monitoring, and treating patients’ diseases or patients who have had organ transplants.

Doctor density varies by specialty and location. The United States has 120 practicing immunopathologists. Broken out by state, immunopathology doctor density in Arizona is 3, in Arkansas is 1, in California is 32, in Colorado is 2, in Connecticut is 2, in District of Columbia is 1, in Florida is 22, in Georgia is 3, in Illinois is 3, in Iowa is 4, in Kansas is 1, in Kentucky is 1, in Louisiana is 3, in Maine is 14, in Maryland is 2, in Massachusetts is 9, in Michigan is 7, in Minnesota is 2, in Missouri is 4, in Nebraska is 3, in New Jersey is 7, in New Mexico is 5, in New York is 22, in North Carolina is 10, in Ohio is 7, in Oregon is 1, in Pennsylvania is 11, in Rhode Island is 1, in South Carolina is 4, in Tennessee is 4, in Texas is 9, in Utah is 2, in Virginia is 3, in West Virginia is 1, and in Wisconsin is 10.