Increased rates of intensive care unit admission in patients with Mycoplasma pneumoniae: a retrospective study

Mycoplasma pneumoniae is a leading cause of respiratory disease. In the Intensive Care Unit (ICU) setting M. pneumoniae is not considered a common pathogen. In 2010-13 an epidemic of M. pneumoniae-associated infections was reported and we observed an increase of M. pneumoniae patients admitted to ICU. We analysed the cohort of all M. pneumoniae-positive patients' admissions during 2007 to 2012 at the Hadassah-Hebrew University Medical Centre (a 1100-bed tertiary medical centre). Mycoplasma pneumoniae diagnosis was made routinely using PCR on throat swabs and other respiratory samples. Clinical parameters were retrospectively extracted. We identified 416 M. pneumoniae-infected patients; of which 68 (16.3%) were admitted to ICU. Of these, 48% (173/416) were paediatric patients with ICU admission rate of 4.6% (8/173). In the 19- to 65-year age group ICU admission rate rose to 18% (32/171), and to 38.8% (28/72) for patients older than 65 years. The mean APACHE II score on ICU admission was 20, with a median ICU stay of 7 days, and median hospital stay of 11.5 days. Of the ICU-admitted patients, 54.4% (37/68) were mechanically ventilated upon ICU admission. In 38.2% (26/68), additional pathogens were identified mostly later as secondary pathogens. A concomitant cardiac manifestation occurred in up to 36.8% (25/68) of patients. The in-hospital mortality was 29.4% (20/68) and correlated with APACHE II score. Contrary to previous reports, a substantial proportion (16.3%) of our M. pneumoniae-infected patients required ICU admission, especially in the adult population, with significant morbidity and mortality.