Mycoplasma pneumoniae is not a respiratory pathogen only: two case reports of ''atypical'' clinical presentations.

Mycoplasma pneumoniae is a common intracellular pathogen, which is responsible for infections of the respiratory tract, particularly in patients between 5 and 30 years of age. Nevertheless, there is increasing evidence that Mycoplasma pneumoniae plays a role in determining clinical presentations different from the respiratory ones. Among extra pulmonary complications skin eruptions are more frequent than others, even with severe clinical features such as Stevens Johnson syndrome. It is important to note that dermatological involvement can occur before, during or after the appearance of respiratory symptoms or without them. We report two patients whose onset of symptoms was not a respiratory tract disease, as usual in Mycoplasma pneumoniae infections, but prolonged and high grade fever with a relevant skin involvement pointing out the importance of researching Mycoplasma pneumoniae in the pathogenesis of peculiar clinical features. The first patient is a 4-year-old boy with signs of Stevens Johnson syndrome while the second patient is a 16-year-old girl with red-purple maculae on both legs and arms; in both cases we detected Mycoplasma IgM antibodies as a part of differential diagnosis. We discuss below the immunological mechanism by which Mycoplasma pneumoniae can determine the clinical features shown by our patients.