Mycoplasma pneumoniae is a cell wall-less organism between a virus and a bacterium. The onset of Mycoplasma pneumoniae infection is slow and most patients are asymptomatic, while a small percentage of patients develop the disease. The typical presentation is a fever, paroxysmal, irritating cough, and a small amount of mucus. Laboratory tests may reveal that the total white blood cell count is within the normal range, with a small percentage of patients having an elevated white blood cell count, and a quarter of patients may have a white blood cell count of more than 10 x 10^9/L. There is a slight increase in neutrophils or eosinophils in the classification, and in a small percentage of patients, there is a decrease in platelets. Serological tests may reveal a 4-fold or greater increase in the potency of the acute duplex serum. IgM or IgG antibodies can also be detected, and generally the IgM antibodies are elevated after 7 days of illness, with a serum titer greater than 1:40.