Journal List > Ann Clin Microbiol > v.16(1) > 1078494

Shin, Kim, Kim, Koh, Lee, Koo, Cho, Kim, and Ryoo: A Multicentre Study about Pattern and Organisms Isolated in Follow-up Blood Cultures

초록

Background

This study analysed patterns of requests for repeated blood cultures and the microorganisms isolated in follow-up cultures.

Methods

The frequencies and intervals of repeated blood cultures performed during January and Feb-ruary of 2010 at seven university-affiliated hospitals in Korea were evaluated. Results of microbiological cultures at follow-up were analysed with respect to pathogen replication, immune clearance, appearance of new pathogens, and skin contaminants.

Results

Among 3,072 patients who received repeated blood cultures, the average number of requests was 3.2. Of the 5,241 follow-up blood culture events recorded, durations of 1, 2, and 3 days between cultures were identified for 23.1%, 21.4%, and 15.0% of events, respectively. Relative to each initial culture, persistent pathogen growth in subsequent culture(s) accounted for 2.3% of events, whereas immune clearance was confirmed in 8.5% of events. Previously undetected pathogens were isolated in 5.2% of the follow-up cultures, the majority of which grew after an interval of six days. Skin contaminants were detected in 7.6% of the repeated cultures, and 76.1% of the follow-ups displayed no growth of microorganisms.

Conclusion

The most common numbers of repeat culture requests were two and three, and these were typically performed within three days of the initial culture. Among the follow-up cultures, new pathogens were identified in 5.2%, and the majority of this group likely presented for follow-up during a new disease episode.

REFERENCES

1.Clinical and Laboratory Standards Institute. Principles and Procedures for Blood Cultures; Approved Guideline. Document M47-A. Wayne PA. Clinical and Laboratory Standards Institute. 2007.
2.Fowler VG Jr., Olsen MK., Corey GR., Woods CW., Cabell CH., Reller LB, et al. Clinical identifiers of complicated Staphylococcus aureus bacteremia. Arch Intern Med. 2003. 163:2066–72.
3.Mylotte JM., Tayara A. Blood cultures: clinical aspects and controversies. Eur J Clin Microbiol Infect Dis. 2000. 19:157–63.
crossref
4.Grace CJ., Lieberman J., Pierce K., Littenberg B. Usefulness of blood culture for hospitalized patients who are receiving antibiotic therapy. Clin Infect Dis. 2001. 32:1651–5.
crossref
5.Sarkar S., Bhagat I., Wiswell TE., Spitzer AR. Role of multiple site blood cultures to document the clearance of bacteremia in neonates. J Perinatol. 2007. 27:101–2.
crossref
6.Hall KK., Lyman JA. Updated review of blood culture contamination. Clin Microbiol Rev. 2006. 19:788–802.
crossref

Table 1.
Summary of initial and follow-up blood culture results (%) by hospital
Initial/follow-up culture Hospitals
A (82) B (279) C (334) D (424) E (447) F (533) G (973) Total (3,072)
Growth/growth 7.3 2.2 1.2 2.6 1.3 3.0 3.1 2.3 (70)
No growth/growth 14.6 5.0 4.5 2.1 4.5 4.7 6.8 5.2 (161)
Growth/no growth 12.2 7.2 4.8 5.7 11.0 6.0 11.3 8.5 (261)
Contaminants 13.4 11.8 2.1 5.0 7.4 8.6 8.3 7.6 (232)
No growth/no growth 52.5 73.8 87.4 84.6 75.8 77.7 70.5 76.4 (2,348)

Number of patients;

Detection of pathogens;

Normal skin flora detected in only one set.

Table 2.
Culture intervals for patients harboring persistently growing microorganisms
Microorganism Interval days
1 2 3 4-6 7 Total (%)
Staphylococcus aureus 7 3 2 3 1 16 (22.9)
Eschericia coli 8 1 1 1   11 (15.7)
Klebsiella pneumoniae 4 1 1   1 7 (10.0)
Enterococcus faecalis 2 5       7 (10.0)
Candida spp. 1   2 2   5 (7.1)
Other Gram (+) bacteria 6 2 1 1 2 12 (17.1)
Other Gram (‒) bacteria 6 2 4     12 (17.1)
Total (%) 34 (48.6) 14 (20.0) 11 (15.7) 7 (10.0) 4 (5.7) 70 (100)
Table 3.
Intervals between blood cultures for cases in which pathogens were identified only upon follow-up culture
Microorganism Interval days
1 2 3 4 5 6 7 Total (%)
Staphylococcus aureus 4 4 3 2 4 1 10 28 (17.4)
Acinetobacter baumannii 2 1 2 2 1 1 5 14 (8.9)
Klebsiella pneumoniae   2   1 1 1 8 13 (8.1)
Eschericia coli 3 1     1 2 4 11 (6.8)
Pseudomonas aeruginosa 1 4         4 9 (5.6)
Candida albicans   1 1     3 4 9 (5.6)
Enterococcus faecium 2 2 1       3 8 (5.0)
Other Gram (+) bacteria 7 8 3 5 3 1 13 38 (23.6)
Other Gram (‒) bacteria 1 6 1 1 3   10 22 (13.7)
Non-albicans Candida 2     1     4 7 (4.3)
Total (%) 23 (14.3) 31 (19.3) 11 (6.8) 12 (7.5) 10 (6.2) 9 (5.6) 65 (40.4) 161 (100)
TOOLS
Similar articles