OBJECTIVETo investigate the clinical features of Mycoplasma pneumoniae pneumonia (MPP) among children of different ages.

METHODSRetrospective analysis was performed on the clinical data of 112 children who were hospitalized due to MMP between January 2010 and December 2011. The children were divided into 3 groups according to their ages: infants (<3 years; n=20), preschool-aged children (≥3 years; n=41), and school-aged children (6-15.2 years; n=51). The three groups were compared in terms of their clinical symptoms, pulmonary signs, chest X-ray findings and laboratory test results.

RESULTSThe infant group presented mainly with expectoration and wheezing, accompanied by low fever. They showed gastrointestinal symptoms as the most common extra-pulmonary manifestation and had evident pulmonary signs. The majority of the school-aged children group presented with high fever and a severe dry cough, and wheezing was seen in several of them. They showed rash as the most common extra-pulmonary manifestation and had slight pulmonary signs. The symptoms of the preschool-aged children group were in between. In the infant and preschool-aged children groups, most showed bronchopneumonia on chest X-ray, while in the school-aged children group, chest X-rays mostly showed segmental parenchymatous infiltration. The infant group had a higher lymphocyte count than the school-aged children group, while the school-aged children group had a higher serum C-reactive protein level than the infant group.

CONCLUSIONSThe clinical features of MPP are different among children of different ages, especially between infants and school-aged children.

Adolescent ; Age Factors ; Antibodies, Bacterial ; blood ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Pneumonia, Mycoplasma ; diagnosis ; diagnostic imaging ; drug therapy ; Radiography, Thoracic ; Retrospective Studies

OBJECTIVETo investigate the effect of granulocyte colony stimulating factor (G-CSF) on myeloid-derived suppressor cells (MDSCs) in the bone marrow and peripheral blood, and explore the relationship between MDSC and graft-versus-host disease (GVHD).

METHODSBone marrow, peripheral blood and peripheral blood stem cells were obtained from 12 healthy hemopoietic stem cell donors before and on day 5 after G-CSF mobilization. Flow cytometry was employed to examine the number of MDSC, and the relationship between MDSC number and the incidence of GVHD was analyzed.

RESULTSIn normal physiological conditions, MDSC could be detected in the peripheral blood and bone marrow with a cell percentages of (1.35±0.35)% and (2.44±1.11)%, respectively, showing a significantly higher cell percentage in the bone marrow (P=0.015). On the 5th day after G-CSF mobilization, the percentage of MDSCs increased to (4.01±1.82)% in the peripheral blood and to (4.38±2.19)% in the bone marrow, showing no significant difference between them (P=0.083). The mobilization caused a significant increase in the number of MDSCs in the peripheral blood (P=0.047) but not in the bone marrow (P=0.761). The number of MDSCs in the collected samples showed a significant inverse correlation to the incidence of GVHD (P=0.048).

CONCLUSIONSMDSCs are present in the peripheral blood and bone marrow of healthy donors, with a greater number in the bone marrow. G-CSF can mobilize the MDSCs from the bone marrow to the peripheral blood to increase number of MDSCs in the peripheral blood, which may contribute to a lowered incidence of GVHD in hematopoietic stem cell transplantation (HSCT).

Adolescent ; Adult ; Bone Marrow Cells ; cytology ; Female ; Graft vs Host Disease ; prevention & control ; Granulocyte Colony-Stimulating Factor ; administration & dosage ; Hematopoietic Stem Cell Mobilization ; methods ; Hematopoietic Stem Cell Transplantation ; Humans ; Male ; T-Lymphocytes ; cytology ; drug effects ; metabolism ; Young Adult