Læknablaðið - 01.03.2022, Qupperneq 24

136 L ÆKNABL AÐIÐ 2022/108
E N G L I S H S U M M A R Y
Anna Kristín Gunnarsdóttir1
Helga Erlendsdóttir2,3
Magnús Gottfreðsson3,4,5
1Department of psychiatry, 2Department of clinical microbiology,
3Department of infectious diseases, 4Faculty of Medicine, School of
Health Sciences, University of Iceland, 5Department of science
Landspitali University Hospital.
Correspondence: Anna Kristín Gunnarsdóttir, annakg@landspitali.is
Key words: Bacillus species, Bacillus cereus, penicillin resistance, invasive
infections. sepsis, epidemiology, diagnostic criteria.
Invasive infections of Bacillus species in Iceland, 2006-2018
INTRODUCTION: The bacterial genus Bacillus is widely distributed environmentally and
is usually considered a low-virulence organism, except for B. anthracis. A blood culture
positive for Bacillus is often looked at as contamination. Nevertheless, B. cereus can cause
invasive infections in humans and produces harmful toxins. The epidemiology of these
infections remains poorly studied.
MATERIAL AND METHODS: All possible invasive infections caused by Bacillus during
2006-2018 at Landspitali University Hospital were identified from culture results.
Clinical information was used to evaluate if there was a possible infection or confirmed
infection. Here, the authors propose and use clinical criteria to categorize each case as
contamination, possible infection or confirmed infection. The incidence of possible or
confirmed infections was calculated using hospital catchment population data.
RESULTS: Positive cultures of Bacillus sp. from sterile sites during 2006-2018 were
identified from 126 patients; blood (116), synovial fluid (8) and cerebrospinal fluid (2).
In total, 26 cases were confirmed infection (20.6%), 10 possible infection (7.9%) and 90
contamination (71.4%). The incidence was 1.4 cases/100.000 inhabitants/year. Injection
drug use was a risk factor among 11/26 patients with confirmed infection. The most
common clinical presentation was sepsis. In this study, Bacillus was resistant to beta-
lactam antibiotics in 92% of confirmed infections and 66% of the cases considered
contamination (p=0.02).
CONCLUSION: Positive blood cultures of Bacillus sp. should be taken seriously, especially
among patients with injection drug use, malignancy or immunocompromised state. It is
important to draw two sets of blood cultures if there is a real suspicion of an infection to
establish diagnosis and avoid unnecessary antibiotic therapy.
doi 10.17992/lbl.2022.03.681
Heimildir
1. Drobniewski FA. Bacillus cereus and related species. Clin Microbiol Reviews 1993; 6: 324­
38.
2. Bottone EJ. Bacillus cereus, a volatile human pathogen. Clin Microbiol Rev 2010; 23: 382­
98.
3. Kutima PM, Foegeding PM. Involvement of the spore coat in germination of Bacillus cer­
eus T spores. Appl Environ Microbiol 1987; 53: 47­52.
4. Mandell GL, Bennet JE, Tuazon DR. Other Bacillus species. Principles and Practice of
Infectious Diseases. Churchill Livingstone, New York 2005.
5. McDowell RH, Sands EM, Friedman H. Bacillus Cereus. StatPearls (internet). ncbi.nlm.nih.
gov/books/NBK459121/­ september 2020.
6. Castedo E, Castro A, Martin P, et al. Bacillus cereus prosthetic valve endocarditis. Ann
Thorac Surg 1999; 68: 2351­2.
7. Hoffmaster AR, Ravel J, Rasko DA, et al. Identification of anthrax toxin genes in a Bacillus
cereus associated with an illness resembling inhalation anthrax. Proc Natl Acad Sci USA
2004; 101: 8449­54.
8. David DB, Kirkby GR, Noble BA. Bacillus cereus endophthalmitis. Br J Opthalmol 1994;
78: 577­80.
9. Ozkocaman V, Ozcelik T, Ali R, et al. Bacillus spp. among hospitalized patients with haem­
atological malignancies: clinical features, epidemics and outcomes. J Hosp Infect 2006; 64:
169­76.
10. Kuroki R, Kawakami K, Qin L, et al. Nosocomial bacteremia caused by biofilm­forming
Bacillus cereus and Bacillus thuringiensis. Intern Med 2009; 48: 791­6.
11. Sasahara T, Hayashi S, Morisawa Y, et al. Bacillus cereus bacteremia outbreak due to
contaminated hospital linens. Eur J Clin Microbiol Infect Dis 2011; 30: 219­26.
12. Baron S. Medical Microbiology 4th edition. University of Texas Medical Branch, Galveston
1996.
13. Weber DJ, Saviteer SM, Rutala WA, et al. In vitro susceptibility of Bacillus spp. to selected
antimicrobial agents. Antimicrob Ageents Chemother 1988; 32: 642­5.
14. European Committee on Antimicrobial Susceptibility Testing. Breakpoint tables for inter­
pretation of MICs and zone diameters. eucast.org/fileadmin/src/media/PDFs/EUCAST_
files/Breakpoint_tables/v_11.0_Breakpoint_Tables.pdf?fbclid=IwAR16THRnicCEEymTx­
sPFKbu4AJsonjfKN5NWZWr_pY6cDmskJBBLFbyJLYE ­ janúar 2019.
15. Duke Criteria for Endocarditis. reference.medscape.com/calculator/67/duke­criteria­for­
endocarditis ­ mars 2019.
16. Veysseyre F, Fourcade C, Lavigne J­P, et al. Bacillus cereus infection: 57 case patients and a
literature review. Med Mal Infect 2015; 45: 436­40.
17. Kato K, Matsumura Y, Yamamoto M, et al. Erratum to : Seasonal trend and clinical
presentation of Bacillus cereus bloodstream infection : association with summer and
indwelling catheter. Eur J Clin Microbiol Infect Dis 2016; 875­83.
18. Wiedermann CJ, Stockner I, Plattner B. Bacillus species infective arthritis after knee
arthroscopy. Surg Infect 2010; 11: 555­8.
19. Hjaltadóttir K. Viðbrögð við jákvæðum blóðræktunum á Landspítala. Janúar til ágúst
2010. BS­lokaverkefni í læknisfræði við Háskóla Íslands, 2010.
20. Káradóttir HL. Kóagulasa neikvæðir stafýlókokkar á Landspítala. Afturvirk rannsókn á
blóðsýkingum árin 2011­2016. BS­lokaverkefni í læknisfræði við Háskóla Íslands, 2018.
21. Ngow HA, Wan Khairina WM. Bacillus cereus endocarditis in native aortic valve. J Infect
Chemother 2013; 19: 154­7.
22. Thomas BS, Bankowski MJ, Lau WKK. Native valve Bacillus cereus endocarditis in a non­
intravenous­drug­abusing patient. J Clin Microbiol 2012; 50: 519­21.