Lack of Usefulness of the Immunochromatographic Urinary Pneumococcal Antigen Test in Maximizing Pneumococcal Yield in a Community-Acquired Pneumonia Clinical Trial

Early etiological diagnosis of acute pneumococcal community-acquired pneumonia (CAP) would be very useful in helping clinicians to prescribe correct antibiotic treatment, in maximizing patient prognosis and avoiding the selection and spread of resistant bacterial strains to the community, above all, in regions with a high prevalence of macrolide-resistant Streptococcus pneumoniae 1. The development of new antibiotics requires robust clinical and microbiological efficacy data. So, every effort to help investigators to identify patients with a high likelihood of pneumococcal involvement and recovery will impact on the total number of subjects to be screened, the study cost and the validity of the study data. So far, the most common laboratory samples used for etiological diagnosis of pneumococcal CAP are blood and expectorated sputum cultures. Blood culture has the highest specificity but a low sensitivity (1% to 16%) 2. Expectorated sputum cannot always be obtained, 3 and samples of good enough quality as to yield a relevant microorganism are difficult to obtain 4. Real-time PCR techniques are still far from being useful in the short and medium terms in clinical practice. The immunochromatographic assay-based rapid Journal of Chemotherapy Vol. 18 n. 5 (562-564) 2006