Increased Macrolide-Resistant Mycoplasma pneumoniae Infections and Response to Doxycycline in Midwest United States.

37 cases of Mycoplasma pneumoniae pneumonia were diagnosed in children in North Dakota, over 3.5 months (35 by PCR); 44% harbored macrolide-resistance. Children with macrolide-resistant M. pneumoniae had a longer period of coughing prior to diagnosis (+ 3.9 days, p=0.048), a longer duration of illness (+ 5.4 days, p=0.011) and earlier resolution of fever after initiation of doxycycline (- 0.92 days, p=0.025) compared to those without macrolide resistant M. pneumoniae.