Mycoplasma Pneumonia in Young Children, 2-5 Years of Age
Thanyanat Bunnag MD*, Sorasak Lochindarat MD*, Panida Srisan MD*, Pravit Jetanachai MD*
Affiliation : * Queen Sirikit National Institute of Child Health, College of Medicine, Rangsit University, Bangkok
Background : Mycoplasma pneumoniae is one of the most common causes of childhood community-acquired
pneumonia (CAP), particularly in school-age children. Information regarding this infection in pre-school
age children is lacking.
Objective : To determine the prevalence of M. pneumoniae in young children aged under 5 years with CAP.
Material and Method: This prospective study was conducted at Queen Sirikit National Institute of Child
Health (QSNICH), Bangkok, Thailand between December 2001 and November 2002. We enrolled children
aged 2 to 5 years with a clinical and radiological diagnosis of CAP. Acute and convalescent sera were
collected and measured by using a particle agglutination test. Polymerase chain reaction (PCR) assay for M.
pneumoniae was detected from nasopharyngeal secretions. Criteria for diagnosis were defined as > 4-found
rising of mycoplasma antibody or titer > 1:160 with positive PCR.
Results : Thirteen out of 113 CAP patients were diagnosed as mycoplasma pneumonia. Three of them were
diagnosed by > 4-fold rising of mycoplasma antibody while another 10 patients were diagnosed by myco-
plasma titer > 1:160 with positive PCR for M. pneumoniae. Clinical symptoms and signs of these 13 myco-
plasma pneumonia in young patients were fever (85%), cough (92%), dyspnea (85%), diarrhea (15%), rales
(85%), wheezing or rhonchi (46%), and skin rash (15%).Leucocytosis (wbc > 15,000/cumm) was found in
46%. Chest x-rays revealed interstitial infiltration (71%), patchy infiltration (29%) and no pleural effusion
was detected. Choices of antibiotic were erythromycin (31%), beta lactam antibiotics (61%), and antibiotic
was not prescribed in one patient (8%). Sixty-nine percent of the patients improved, while 31% did not,
possibly due to the use of beta lactam antibiotics, or non use of antibiotics.
Conclusion : Mycopalsma pneumonia is not uncommon in children aged 2-5 years with CAP. Clinical signs,
symptoms and radiological findings are non-specific and cannot be differentiated from other causes of CAP.
Keywords : Mycoplasma pneumoniae, Children, Community-acquired pneumonia
