mp-IgM is the abbreviation and acronym for Mycoplasma pneumoniae IgM antibodies. Mycoplasma pneumoniae is a relatively common pathogenic bacterium that is different from common bacteria, and is an inflammatory and microorganism without a cell wall. Mycoplasma pneumoniae infection can stimulate the body to produce two specific antibodies, one for Mycoplasma pneumoniae IgM and the other for Mycoplasma pneumoniae IgG. In clinical practice, antibodies are often tested to determine the presence of Mycoplasma pneumoniae infection and the effectiveness of treatment. A positive IgG test indicates a previous Mycoplasma pneumoniae infection, while a positive IgM test indicates a possible acute infection. Since IgM is present in the body for a longer period of time, the diagnosis of Mycoplasma pneumoniae infection can be confirmed if the IgM level is four times higher or four times lower during the recovery period of Mycoplasma pneumoniae infection than during the acute infection. Therefore, mp-IgM is an important indicator for the diagnosis of Mycoplasma pneumoniae.