Guideline for Antibiotic Use in Adults with Community-acquired Pneumonia

Lee, Mi Suk; Oh, Jee Youn; Kang, Cheol-In; Kim, Eu Suk; Park, Sunghoon; Rhee, Chin Kook; Jung, Ji Ye; Jo, Kyung-Wook; Heo, Eun Young; Park, Dong-Ah; Suh, Gee Young; Kiem, Sungmin

A S. pneumoniae urinary antigen test is performed for all patients with community-acquired pneumonia who require hospitalization. The urinary antigen test for S. pneumoniae detection produces results within 15 minutes, and can give positive results even when antibiotics are administered. It is reported to have sensitivity of 50-80% and specificity of over 90% for adults [82] [83] [84] . The drawbacks of this test are that it is expensive to perform, and it does not assess antibiotic susceptibility. It can also produce false positive results in pediatric patients with chronic lung diseases characterized by S. pneumoniae colonization, and patients who suffered from community-acquired pneumonia in the last four months [85, 86] . The test is unaffected by the normal bacterial flora in patients with chronic obstructive pulmonary disease [78, 85] . The positivity rate of the S. pneumoniae urinary antigen test and the severity of pneumonia are reported to be correlated [87] . In 80-90% of patients who tested positive in the S. pneumoniae urinary antigen test, positivity continue until 7 days after treatment was begun [88] , and the test can be performed using other bodily fluids such as pleural fluid [89] . Among studies on the effects of the results of S. pneumoniae urinary antigen test on treatment, a retrospective study has reported that pneumonia caused by S. pneumoniae was safely and effectively treated by high-dose penicillin administration in patients who tested positive in the S. pneumoniae urinary antigen test [90] . KQ 3. Is the Legionella urinary antigen test helpful for selecting therapeutic antibiotics for adults who may have contracted community-acquired pneumonia?