Alpha hemolysis: When bacteria are cultured on a blood plate, a narrow (1-2mm), grass-green hemolytic ring is formed around the colony. The red blood cells in the α hemolysis ring are not completely dissolved. Bacteria that can form alpha hemolytic loops, such as streptococcus A hemolyticus and Streptococcus pneumoniae.
Umbilical colonies: pneumococcus has autolysing enzymes, and autolysis of bacteria can make the middle of the colonies sunken into an umbilical shape after a longer culture time. Since both pneumococcus and streptococcus A form an alpha hemolytic ring on the blood plate, the morphology of the colony is similar, so the umbilical colony is one of the basis for distinguishing the two.
Beta hemolysis: When bacteria are cultured on a blood plate, a wide (2～4mm), well-defined, completely transparent hemolysis ring is formed around the colony. The red blood cells in the beta hemolysis ring are completely lysed. Bacteria that can form beta hemolytic loops, such as beta-hemolytic streptococcus, Staphylococcus aureus, etc.
Gamma hemolysis: means no hemolysis.
⒈Patients with a history of spontaneous abortion and a history of jaundice in the previous baby.
⒉Blood type examination is O type, and her husband is A, B or AB type.
⒊O-type blood expectant mother before pregnancy finds out those with higher anti-A or anti-B antibody titer.
⒋The anti-A(B) IgG titer of pregnant mothers with type O blood>1:64.
⒌B-ultrasound examination during pregnancy, severe hemolysis can show fetal skin edema, hepatosplenomegaly, etc.
The occurrence of neonatal hemolysis mainly has the following two situations:
⑴Mothers with blood type O and fetuses with type A or B are susceptible to "ABO hemolysis" and "ABO hemolysis" mostly in the second pregnancy, but it can also partially occur in the first pregnancy. If a mother with blood type O has transfused blood of blood type A or B or AB before giving birth, or has a history of miscarriage (the mother's birth canal is broken and the blood of the fetus is knocked out into the body), the mother will produce anti-A or anti-B antibodies. Then even the first child may have neonatal hemolysis.
⑵The mother is Rh-negative and the fetus is Rh-positive, prone to "Rh hemolytic disease"
Rh blood type incompatibility hemolysis usually occurs after the second child, and the first child is heavier than the first child. The mother who has received Rh blood type transfusion can develop the disease in the first child.
Generally speaking, Rh hemolysis is severe, and ABO hemolysis is light. In China, hemolysis caused by ABO system incompatibility is more common, followed by hemolysis caused by Rh blood group incompatibility.