Coombs test refers to the antiglobulin test, which is meant to identify the presence of autoimmune hemolytic anemia, systemic lupus erythematosus, and so on. Consultation with a specialist is recommended. Coombs test is often categorized into direct Coombs test and indirect Coombs test. A positive direct Coombs test indicates that incomplete antibodies are bound to the surface of red blood cells, while a positive indirect Coombs test indicates the presence of incomplete antibodies in the patient’s serum. Normally, both the direct Coombs test and the indirect Coombs test are negative. If positive it is commonly seen in hemolytic disease of the newborn, autoimmune hemolytic anemia, systemic lupus erythematosus, rheumatoid arthritis, certain lymphomas, and drug-induced hemolytic reactions such as methyldopa and penicillin types. The indirect Coombs test is commonly used to detect Rh or ABO pregnancy-immune hemolytic disease of the newborn and incomplete antibodies in the maternal serum. A positive Coombs test requires prompt diagnosis and treatment.