Korean J Lab Med.  2007 Jun;27(3):216-220. 10.3343/kjlm.2007.27.3.216.

Emergence of beta-Lactam-Dependent Bacillus cereus associated with Prolonged Treatment with Cefepime in a Neutropenic Patient

• Ko SY
• Chung HJ
• Sung HS
• Kim MN

• KMID: 1781487
• DOI: http://doi.org/10.3343/kjlm.2007.27.3.216

Abstract

Antibiotic dependence in clinical isolates has been reported, albeit rarely, such as vancomycindependent enterococcus and beta-lactam-dependent Staphylococcus saprophyticus. We report herein a clinical isolate of beta-lactam-dependent Bacillus cereus. A 16-yr-old female was admitted on 8 September 2005 with neutropenic fever during chemotherapy following surgical removal of peripheral neuroectodermal tumor. She had had an indwelling chemoport since August 2004 and experienced B. cereus bacteremia three times during the recent 3-month period prior to the admission; the bacteremias were treated with cefepime-based chemotherapy. On hospital days 1 and 3, B. cereus was isolated from blood drawn through the chemoport. The isolates were resistant to penicillin, ceftriaxone, and erythromycin, and susceptible to vancomycin and ciprofloxacin. The isolate of hospital day 3 grew only nearby the beta-lactam disks including penicillin and ceftriaxone on disk diffusion testing. The beta-lactam-dependent isolate required a minimum of 0.064 microgram/mL of penicillin or 0.023 microgram/mL of cefotaxime for growth, which was demonstrated by E test (AB Biodisk, Sweden). Light microscopy and transmission electron microscopy revealed a marked elongation of the dependent strain compared with the non-dependent strain. Prolonged therapy with beta-lactams in the patient with an indwelling intravenous catheter seemed to be a risk factor for the emergence of beta-lactam-dependence in B. cereus.

Keyword

beta-lactam-dependent; Bacillus cereus; Chemoport

MeSH Terms

Adolescent
Anti-Bacterial Agents/therapeutic use
Bacillaceae Infections/*drug therapy/microbiology
Bacillus cereus/cytology/*drug effects/isolation & purification
Bacteremia/drug therapy/microbiology
Cephalosporins/*therapeutic use
Female
Humans
Microbial Sensitivity Tests
Neutropenia/*complications/etiology
Risk Factors
*beta-Lactam Resistance

Figure

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  Fig. 1. Summary of blood culture results and antimicrobial treatment. Bacillus cereus were isolated from chemoport blood culture but not from peripheral blood culture on June 30, 2005, July 21, 2005, July 31, 2005, September 8, 2005 (hospital day 1), and September 10, 2005 (hospital day 3). β-lactam-dependent B. cereus was isolated on chemoport blood culture on Sep 10, 2005.

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  Fig. 2. Antimicrobial susceptibility tests with penicillin (P), ceftriaxone (CRO), erythromycin (E), vancomycin (VA), and ciprofloxacin (CIP) disks for β-lactam-independent Bacillus cereus isolated on hospital day 1 (A) and β-lactam-dependent B. cereus isolated on hospital day 3 (B). β-lactam-dependent isolates showed growth only around the penicillin or ceftriaxone disk. The results of E test with penicillin (C) and cefotaxime (D) showed the degree of β-lactam-dependence. The β-lactam-dependent isolate required a minimum of 0.064 μg/mL of penicillin (PG) or 0.023 μg/mL of cefotaxime (CT) for growth.

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  Fig. 3. Light microscopy (Gram stain, × 1,000) and electron microscopy (TEM, × 8,000) of β-lactam-independent (A) and β-lactam-dependent B. cereus(B). Predominance of markedly elongated rods in the β-lactam-dependent strain is noted.

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  Fig. 4. PFGE analysis of B. cereus isolated at July 31, 2005 (lane 1), hospital day 1 (lane 2), hospital day 3 (lane 3), respectively, after restriction with SmaI. B. cereus isolated at July 31, 2005 was closely related to the subsequent two isolates recovered at hospital day 1, which was β-lactam-independent, and hospital day 3, which was β-lactam-dependent, with only one restriction band difference. Isolates on hospital day 1 and hospital day 3 were identical with each other. Lane M, a concatamer of phage λ DNA as a size standard (New England BioLabs Inc., Ipswich, MA, USA). Abbreviations: ppl, peripheral; N.G., no growth.

Reference

References

1. Winn WC, Allen SD, editors. Color atlas and textbook of diagnostic microbiology. 6th ed.Philadelphia: J.B. Lippincott;2005. p. 778–81.

2. Christenson JC, Byington C, Korgenski EK, Adderson EE, Bruggers C, Adams RH, et al. Bacillus cereus infections among oncology patients at a children's hospital. Am J Infect Control. 1999; 27:543–6.

3. Srivaths PR, Rozans MK, Kelly E Jr, Venkateswaran L. Bacillus cereus central line infection in an immunocompetent child with hemophilia. J Pediatr Hematol Oncol. 2004; 26:194–6.

4. Fraimow HS, Jungkind DL, Lander DW, Delso DR, Dean JL. Urinary tract infection with an Enterococcus faecalis isolate that requires vancomycin for growth. Ann Intern Med. 1994; 121:22–6.

5. Yowler CJ, Blinkhorn RJ, Fratianne RB. Vancomycin-dependent ente-rococcal strains: case report and review. J Trauma. 2000; 48:783–5.

6. Worthington T, White J, Lambert P, Adlakha S, Elliott T. β-lactam-dependent coagulase-negative staphylococcus associated with urinary-tract infection. Lancet. 1999; 354:1097.

7. Green M, Shlaes JH, Barbadora K, Shlaes DM. Bacteremia due to vancomycin-dependent Enterococcus faecium. Clin Infect Dis. 1995; 20:712–4.

8. Murray BE. Vancomycin-resistant enterococci. AM J Med. 1997; 102:284–93.

9. Lorian V. Antibiotics in laboratory medicine. 4th ed.New York: Williams and Wilkins;1996. p. 397–414.

10. Tambyah PA, Marx JA, Maki DG. Nosocomial infection with vancomycin-dependent enterococci. Emerg Infect Dis. 2004; 10:1277–81.