CHUARD C, FRACHEBOUD D, PERRIARD F, REGAMEY C; Interscience Conference on Antimicrobial Agents and Chemotherapy.

Abstr Intersci Conf Antimicrob Agents Chemother Intersci Conf Antimicrob Agents Chemother. 1999 Sep 26-29; 39: 189 (abstract no. 207).

Hosp. Cantonal, Fribourg, SWITZERLAND.

BACKGROUND: Quite often, clinicians requesting sputum bacteriology order the collection of multiple specimens to increase the odds of obtaining at least one specimen that is not contaminated by oropharyngeal flora.METHODS: Using the laboratory computer system, we assessed retrospectively the utility of submitting multiple specimens to obtain good quality sputum as judged by the polymorphonuclear neutrophils / squamous epithelial cells ratio on Gram stain (modified Q score). Requests for mycobacteriology were excluded.RESULTS: During a 18-month period, 1086 sputum specimens were sent to the microbiology laboratory for bacteriological examination; 574 were single specimens and 512 belonged to 209 sets of multiple specimens collected during the same or consecutive days (126 sets with 2 specimens, 74 sets with 3 specimens, 7 sets with 4 specimens and 2 sets with 5 specimens). The 209 sets came from 188 patients (117 males; mean age 68.5 years, SD 15.8). The first specimen submitted was of good quality in 146/209 sets (70%) and of poor quality in 63/209 sets (30%). For the 146 episodes with a good quality first specimen, 220 following specimens were processed superfluously. For the 63 episodes with a contaminated first specimen, 81 following specimens were processed; 49 (60%) of them were of poor quality and 32 (40%) were of good quality. The analysis of the 63 sets with a contaminated first specimen showed that the probability of a good quality second specimen was 41% (26/63); when the first and the second specimens were contaminated, the probability of a good quality third specimen was 11% (1/9).CONCLUSION: Initial ordering of multiple specimens for sputum bacteriology is not cost-effective since in most cases the first specimen is of good quality. When the quality of the first specimen is poor, submitting a second one may be useful. If the first and the second specimens are contaminated, additional specimens should not be sent to the microbiology laboratory.

Publication Types:

• Meeting Abstracts

Keywords:

• Bacteriology
• Humans
• Laboratory Techniques and Procedures
• Male
• Neutrophils
• Respiratory System
• Sputum
• microbiology

Other ID:

• GWAIDS0007777

UI: 102245274

From Meeting Abstracts