Analysis of distribution and drug resistance of pathogens isolated from 541 hospitalized children with burn infection

Objective To investigate the distribution and drug resistance of pathogens isolated from hospitalized children with burn infection. Methods Totally 541 patients were hospitalized in Fujian Medical University Union Hospital, the 180th Hospital of Chinese People′s Liberation Army(PLA), the 92th Hospital of PLA, and Longyan First Hospital from January 2013 to December 2015. Totally 848 clinical specimens (blood, catheter tip attachments, wound exudate, etc.) were collected for pathogen detection. After being identified by an automatic microbiological identification system, drug resistance of pathogens to 41 commonly-used antibiotics in clinic including gentamicin, aztreonam, erythromycin, clindamycin, etc. was tested by K-B paper disk diffusion method or minimal inhibitory concentration detection method. The SPSS 20.0 statistical software was used to analyze the following subjects: the detection rates of pathogens in different years, from different hospitals, and with different sources, the distribution of gram-negative bacteria, gram-positive bacteria, and fungi, the distribution of major pathogens, the detection rate of methicillin-resistant Staphylococcus, the resistant rates of common gram-positive bacteria and gram-negative bacteria to antibiotics. Results The total detection rate of pathogens was 35.14% (298/848). The detection rates of pathogens were 52.29% (114/218), 33.20% (83/250), and 26.58% (101/380) in 2013, 2014, and 2015 respectively, 38.45% (198/515), 51.43% (18/35), 71.70% (38/53), and 17.96% (44/245) from Fujian Medical University Union Hospital, the 180th Hospital of PLA, the 92th Hospital of PLA, and Longyan First Hospital respectively, and 136/261, 8/137, 3/4, and 7/48 from wound exudate, blood, drainage fluid or tissue fluid, and the other specimens (including catheter tip attachments, sputum, feces) respectively. Among the 298 pathogens, 159 (53.36%) strains were gram-positive bacteria, 129 (43.29%) strains were gram-negative bacteria, and 10 (3.36%) strains were fungi. The detection rate of Staphylococcus aureus was the highest, totally 68 strains, accounting for 22.82%, followed by Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus epidermidis, with 37, 31, and 22 strains, accounting for 12.42%, 10.40%, and 7.38% respectively. Among Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA) accounted for 70.59% (48/68). Among Staphylococcus epidermidis, methicillin-resistant Staphylococcus epidermidis (MRSE) accounted for 68.18% (15/22). The resistant rates of MRSA and MRSE to penicillin and ampicillin were all 100.0%, and the resistant rates of MRSA to erythromycin, tetracycline, clindamycin and those of MRSE to erythromycin, cotrimoxazole were high. The high resistant rate of Pseudomonas aeruginosa towards antibiotics was detected with cotrimoxazole (83.3%) only. The resistant rates of Acinetobacter baumannii towards piperacillin, ceftazidime, and cotrimoxazole were high (from 58.8% to 71.4%). Conclusions During the three years, there is large difference in the detection rate of pathogens from these four hospitals in Fujian province. The majority of pathogens were Gram-positive bacteria. The four dominant pathogens were Staphylococcus aureus, Pseudomonas aeruginosa, Acinetobacter baumannii, and Staphylococcus epidermidis. Most of the pathogens were resistant to antibiotics commonly used in clinic in different degree, especially MRSA, MRSE and Acinetobacter baumannii, which showed high resistance towards antibiotics.