Clinical features predicting failure of pathogen identification in patients with community acquired pneumonia

Abstract

Community acquired pneumonia (CAP) is caused by a variety of microorganisms. By identifying patients at risk for failure of pathogen identification, it is possible to make an early decision on the extent of diagnostic procedures to be performed. This is especially important in patients with severe CAP. The aim of this study was to identify these patients by using clinical and laboratory features. In 201 patients hospitalized for CAP, clinical and laboratory variables were collected. Pathogen identification was performed by culture of sputum and blood, urine antigen tests, polymerase chain reaction of sputum, serological testing and viral culture of the pharynx. In 128 patients a respiratory microorganism was identified. In both univariate and multivariate analysis, failure of pathogen identification was predicted by pre-hospital antibiotic therapy, a medical history of hypertension and a low C-reactive protein. We conclude that patients with pre-hospital antibiotic therapy, a medical history of hypertension and a relatively low C-reactive protein are at risk for failure of pathogen identification. These predictors should be confirmed in a larger population. Invasive testing in high-risk patients with CAP in the presence of these predictors should be considered at an early phase of hospitalization.

Antibiotic screening of urine culture as a tool for internal quality audit

“…2 The false-negative UABA could also indicate the empiric antibiotic to be used by the physician in the treatment of the suspected UTI. In our study, 60.1 per cent of positive UABAs showed no growth, re-emphasising the fact from earlier studies 2,[8][9][10] that samples sent to the microbiology laboratory during a course of antibiotic treatment may not yield clinically significant results.…”

“…3 The absence of pyuria provides strong evidence against the presence of urinary tract infection. 10,12 However, sterile pyuria (3.9 per cent of cases with pus cells ≥ 10/HPF in our Obtaining recent antibiotic history from a patient and including it in the request forms is often neglected, and this diagnostic information can influence interpretation of culture results. Limited sensitivity of urine cultures due to prior antibiotic consumption enforces the need to take proper history and avoid sending such samples for culture to the microbiology lab.…”

Antibiotic screening of urine culture as a useful quality audit

“…The false-negative UABA could also indicate the empiric antibiotic to be used by the physician in the treatment of the suspected UTI. In this study, 88.92% of positive UABAs showed no growth, reemphasizing the fact that samples sent to the microbiology laboratory during a course of antibiotic treatment may not yield clinically significant results [6,9]. Efficacy on the selection of antimicrobial agents using cultures repeated two to three days after beginning therapy as suggested by Barsanti et al [8] cannot be recommended as evidenced from our study.…”

“…The absence of pyuria provides strong evidence against the presence of urinary tract infection [9,11,14]; however, sterile pyuria should induce a high suspicion of antibiotic usage [3] and if urinary tract infection is further suspected as in our study, i.e., when pus cells ≥ 10/HPF (29.64%), alternative systems using non culture based systems may be effective in diagnosing such infectious agents.…”

Microbial evaluation of proton-pump inhibitors and the risk of pneumonia

“…Cases were patients with confirmed pneumonia who participated in two clinical trials [16,17] , ,4610 6 cells?L -1 or .10% rods in leukocyte differentiation); and C-reactive protein more than three times the upper limit of normal. Patients who were immunocompromised (haematological malignancies or immunosuppressive therapy, including the use of .20 mg prednisone equivalent per day for .3 days) were excluded.…”