Bacillus anthracis: Difference between revisions

Revision as of 02:43, 23 October 2022

Gram-positive bacillus that is distinguished from other Bacillus by being non-motile and non-hemolytic
Colonies are gray, flat, and may have a "Medusa head" or "comet" appearance
The main toxin has subunits A and B
- A subunit may be either EF (edema factor) or LF (lethal factor)
- B subunit is the protective antigen, against which antibodies react
Lives in soil
Wild and farm animals that have contact with contaminated soil is a common exposure, including to wool and animal hides
Can also be acquired by inhalation of spores

Caused by inoculation of spores into soft tissue
Incubation period of 2 to 5 days
Lesion develops at site of inoculation, starting as erythemaous papule, then ulceration, then eschar
May progress to sepsis

Caused by inhalation of spores
Also known as woolsorter's disease
Start with malaise, fever, and nonproductive cough, followed by respiratory distress, severe pulmonary edema, and death

Inhalational anthrax: ciprofloxacin 400 mg IV q12h ± a second antibiotics
Cutaneous anthrax (mild): ciprofloxacin 500 mg p.o. q12h, doxycycline 100 mg p.o. q12h, or amoxicillin 500-1000 mg p.o. q8h
- Duration typically 7 to 10 days (naturally acquired) or 60 days (bioterrorism-related)
Meningitis: ciprofloxacin plus meropenem plus linezolid
- Duration 2-3 weeks, then prophylaxis to complete 60 days
Almost universally susceptible to ciprofloxacin and doxycycline^[1]
Generally susceptible to penicillin, though should wait for susceptibility results before using
Often resistant to extended-spectrum β-lactams such as ceftriaxone and ceftazidime, as well as aztreonam and TMP-SMX

↑ Tucker Maxson, Thiphasone Kongphet-Tran, Thitipong Mongkolrattanothai, Tatiana Travis, Katherine Hendricks, Corinne Parker, Heather P McLaughlin, Julia Bugrysheva, Frank Ambrosio, Pierre Michel, Blake Cherney, Christine Lascols, David Sue, Systematic Review of In Vitro Antimicrobial Susceptibility Testing for Bacillus anthracis, 1947–2019, Clinical Infectious Diseases, Volume 75, Issue Supplement_3, 15 October 2022, Pages S373–S378, https://doi.org/10.1093/cid/ciac520

@@ Line 32: / Line 32: @@
 *Infects oropharynx or abdomen
 *Causes sepsis{{DISPLAYTITLE:''Bacillus anthracis''}}
+== Management ==
+* Inhalational anthrax: [[ciprofloxacin]] 400 mg IV q12h  ± a second antibiotics
+* Cutaneous anthrax (mild): [[ciprofloxacin]] 500 mg p.o. q12h, [[doxycycline]] 100 mg p.o. q12h, or [[amoxicillin]] 500-1000 mg p.o. q8h
+** Duration typically 7 to 10 days (naturally acquired) or 60 days (bioterrorism-related)
+* Meningitis: [[ciprofloxacin]] plus [[meropenem]] plus [[linezolid]]
+** Duration 2-3 weeks, then prophylaxis to complete 60 days
+* Almost universally susceptible to [[ciprofloxacin]] and [[doxycycline]]<ref>Tucker Maxson, Thiphasone Kongphet-Tran, Thitipong Mongkolrattanothai, Tatiana Travis, Katherine Hendricks, Corinne Parker, Heather P McLaughlin, Julia Bugrysheva, Frank Ambrosio, Pierre Michel, Blake Cherney, Christine Lascols, David Sue,  Systematic Review of In Vitro Antimicrobial Susceptibility Testing for ''Bacillus anthracis'', 1947–2019, ''Clinical Infectious Diseases'', Volume 75, Issue Supplement_3, 15 October 2022, Pages S373–S378, <nowiki>https://doi.org/10.1093/cid/ciac520</nowiki></ref>
+* Generally susceptible to [[penicillin]], though should wait for susceptibility results before using
+* Often resistant to extended-spectrum β-lactams such as [[ceftriaxone]] and [[ceftazidime]], as well as [[aztreonam]] and [[TMP-SMX]]
 [[Category:Gram-positive bacilli]]