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What is Donath landsteiner test is used in diagnosis of ?- and explain in detail?
Paroxysmal cold haemoglobinuria (PCH). In PCH, cold antibody is an IgG antibody (Donath-Landsteiner antibody) which is directed against P blood group antigen and brings about complement-mediated haemolysis. Attacks of PCH are precipitated by exposure to cold. PCH is uncommon and may be seen in association with teiary syphilis or as a complication of ceain infections such as Mycoplasma pneumonia, flu, measles and mumps HARSH MOHAN Text book of pathology 6th edition pg no 313