In this retrospective study, 75 primary care institutions in Guizhou Province were selected to describe the prescription patterns of antibacterial drugs among children in 2020. Overall, the rate of antibiotic prescriptions was highest in the fourth quarter, followed by the first quarter. Among them, penicillins and cephalosporins were the most commonly used antibiotics in outpatient primary care institutions. Sixty-nine percent of antibiotic prescriptions were inappropriate. The most common childhood diseases were the diseases of the respiratory system (86.8%), followed by diseases of the digestive system (6.0%) and diseases of the skin and subcutaneous tissue (2.1%). Penicillins (63.6%) and cephalosporins (18.8%) were the most commonly used antibiotics. Physicians with lower professional titles and more than 40 years of work duration were relatively more likely to prescribe inappropriate antibiotics.
Acute upper respiratory infections (J06, J03, J02, J00, J04) was the most common disease associated with antibiotic prescribing in children, accounting for 74.9%. In addition, although penicillins (63.7%) and cephalosporins (18.8%) accounted for a large proportion, the inappropriate rate of aminoglycosides (99.9%) and lincosamides (98.6%) was the highest. The top two diseases corresponding to aminoglycosides and lincosamides were acute upper respiratory infections of multiple and unspecifed sites, J06 (30.5%, 45.7%), and acute tonsillitis, J03 (18.3%, 17.0%) (additional file S2). Another study from China reported an antibiotic prescription rate for acute upper respiratory tract infections in children of 77.6% while other countries reported rates ranging from 28.7% (Japan) − 76.2% (Albania) [28–32]. However, the guidelines for the clinical application of antibiotics in China  and the United States CDC  state that acute upper respiratory tract infections are the most common community-acquired infections, most commonly caused by rhinoviruses, coronaviruses, influenza viruses, parainfluenza viruses, adenoviruses, and sometimes enteroviruses. Its course of disease is self-limited, generally do not require antibiotic treatment, and symptomatic treatment can be cured, especially in children. Hence, the use of antibiotics for acute upper respiratory tract infections, let alone lincosamides and aminoglycosides, was inappropriate because it may trigger allergies, infections, and even endanger the child’s life . This scenario likely to lead to AMR in children. The use of antibiotics in children is more likely to kill susceptible strains, leading to proliferation of resistant strains and replacement of susceptible strains, resulting in a sharp increase in drug resistance of bacteria .
Overall, unnecessary use of antibiotics accounted for 63.6% of all antibiotic prescriptions. The unnecessary use of antibiotics was found in the top 10 systemic diseases. It should be noted that the 10 sub-diseases under symptoms, signs and abnormal clinical and laboratory findings not elsewhere classified (R10, R05, R59, R50, R04, R07, R51, R22, R21, R11) were all diseases for which antibiotics are unnecessary. The rate of inappropriate antibiotics use for these diseases often reached 100%. When treating such childhood diseases, physicians should make specific clinical diagnoses based on typical signs and symptoms [17, 26]. It is particularly important to stress that when physicians suspect a child has severe pneumonia according to typical signs and symptoms, the child should be transferred to a superior hospital in a timely manner . According to National Health Commission of China for Guiding Principle of Clinical Use of Antibiotics introduced in 2015, there is a very limited range of antibiotics suitable for use by those aged 18 years and under . Physicians should be more cautious about prescribing antibiotics for children as widespread use could exacerbate AMR.
We also found from those antibiotic prescriptions with incorrect spectrum of antibiotics accounted for 4.9% of all antibiotic prescriptions. Except for the systemic disease of symptoms, signs and abnormal clinical and laboratory findings not elsewhere classified, the other 9 systemic diseases all had the condition of incorrect spectrum of antibiotics. Diseases of the eye and adnexa had the highest proportion of incorrect spectrum of antibiotics (37.0%). The proportion of incorrect spectrum of antibiotics was highest in the sub-disease (keratitis) of diseases of the eye and adnexa (97.8%). Penicillins, cephalosporins, macrolides, lincosamides and nitroimidazoles are the incorrect spectrum of antibiotics for these particular diseases. According to Ophthalmology Clinical Guidelines of American Academy of Ophthalmology (2nd edition) , Ophthalmology of China (9th edition)  and National Health Commission of China for Guiding Principle of Clinical Use of Antibiotics introduced in 2015 , quinolones and aminoglycosides are the preferred medication for keratitis treatment, especially in children.
In this study, intravenous antibiotics were more likely to be inappropriate than oral antibiotics. Wang et al.  also showed similar results in intravenous antibiotics. In addition, it was easier to prescribe appropriate antibiotics in the first quarter than in the other three. This may be due to the high incidence of infectious diseases in winter and spring [39, 40]. However, most of them were viral infectious diseases.
In our study, the majority of inappropriate antibiotic prescriptions were prescribed by physicians older than 40 years, with lower professional titles (resident physician / attending physician) and more than 40 years of work duration. Their education was mostly non-undergraduate, and their professional knowledge and experience are often inadequate. Based on this result, it may be necessary to provide refresher courses in antibiotic prescribing for these primary care physicians [41, 42]. Training should emphasize avoiding incorrect and unnecessary use of antibiotic prescriptions in children.
We found that inappropriate antibiotic prescription in children may be correlated with gender of children. It may be related with the fact that left-behind children in rural areas of China are often cared for by poorly educated grandparents, as well as gender discrimination. In addition, children aged 0–1 are more likely than any other age group to be prescribed inappropriate antibiotics. This may be related to physicians using antibiotics recommended for children in China’s antimicrobial guidelines (e.g., third-generation cephalosporins) instead of antibiotics prohibited (e.g., gentamicin in aminoglycosides) [43, 44]. A study by Elong et al  also reported that the main reason for children’s inappropriate use of antibiotics was that their parents could not correctly understand the harm of antibiotics. Antibiotics are sometimes considered as a panacea. Therefore, more information about antibiotic use, such as easy-to-understand brochures and learning videos, should be provided to caregivers of children.
Our study has several limitations. First, the study subjects in primary care institutions may not fully represent the general population of children in China. Second, the time frame of the survey was only one year, thus we could not judge whether the prevalence of paediatric diseases and antibiotic use differed over several years [46, 47].