Systematic Review of Hospital Treatment Outcomes for Naturally Acquired and Bioterrorism-Related Anthrax, 1880–2018

Abstract

Background Bacillus anthracis can cause anthrax and is a potential bioterrorism agent. The 2014 Centers for Disease Control and Prevention recommendations for medical countermeasures against anthrax were based on in vitro data and expert opinion. However, a century of previously uncompiled observational human data that often includes treatment and outcomes is available in the literature for analysis. Methods We reviewed treatment outcomes for patients hospitalized with anthrax. We stratified patients by meningitis status, route of infection, and systemic criteria, then analyzed survival by treatment type, including antimicrobials, antitoxin/antiserum, and steroids. Using logistic regression, we calculated odds ratios and 95% confidence intervals to compare survival between treatments. We also calculated hospital length of stay. Finally, we evaluated antimicrobial postexposure prophylaxis (PEPAbx) using data from a 1970 Russian-language article. Results We identified 965 anthrax patients reported from 1880 through 2018. After exclusions, 605 remained: 430 adults, 145 children, and 30 missing age. Survival was low for untreated patients and meningitis patients, regardless of treatment. Most patients with localized cutaneous or nonmeningitis systemic anthrax survived with 1 or more antimicrobials; patients with inhalation anthrax without meningitis fared better with at least 2. Bactericidal antimicrobials were effective for systemic anthrax; addition of a protein synthesis inhibitor(s) (PSI) to a bactericidal antimicrobial(s) did not improve survival. Likewise, addition of antitoxin/antiserum to antimicrobials did not improve survival. Mannitol improved survival for meningitis patients, but steroids did not. PEPAbx reduced risk of anthrax following exposure to B. anthracis. Conclusions Combination therapy appeared to be superior to monotherapy for inhalation anthrax without meningitis. For anthrax meningitis, neither monotherapy nor combination therapy were particularly effective; however, numbers were small. For localized cutaneous anthrax, monotherapy was sufficient. For B. anthracis exposures, PEPAbx was effective.

Early Hormone Administration and Antibiotic Treatment is Key to Managing Cutaneous Anthrax

“…Edema is the primary clinical manifestation of cutaneous anthrax, and its duration determines the length of hospital stay [3,10,11,12]. In this study, 76 patients were evaluated, 53 of whom had moderate or greater perifocal edema, and 35 patients also experienced signi cant systemic toxic symptoms, such as fever.…”

“…It can be classi ed into ve main clinical types: cutaneous anthrax, pulmonary anthrax, gastrointestinal anthrax, anthrax sepsis, and anthrax meningitis [8, 9,10,11]. Cutaneous anthrax is the most prevalent type, accounting for over 95% of all anthrax cases [11,12]. The initial symptoms of cutaneous anthrax include rash, papules, and blisters of unknown origin on exposed areas like the hands, forearms, face, and neck.…”

Rapidin vitroactivity of telavancin againstBacillus anthracisandin vivoprotection against inhalation anthrax infection in the rabbit model

“…The CDC recently sponsored and published an Anthrax Preparedness supplement [41] with over a dozen articles in response to bioterrorism concerns, given the potential for B. anthracis to be weaponized. Since prospective studies in humans are limited, the CDC evaluated the effectiveness of various classes and combinations of antimicrobials by reviewing the outcomes of over 600 patients hospitalized with anthrax published over the last century [42] and concluded combination therapy to be superior to monotherapy for inhalation anthrax; however, neither monotherapy nor combination treatment is effective against anthrax meningitis. These findings highlight the unmet need for anthrax meningitis and in vivo studies to evaluate new antimicrobials and determine whether these new and current anti-anthrax agents penetrate the blood-brain barrier to be effective treatments for anthrax meningitis.…”

Cutaneous anthrax causing periorbital cellulitis – A rare entity in current era

“…Specific risk factors of animal exposure is often associated with it. Isolated eyelid and periorbital involvement is very rare in tropical countries with only few cases reported in literature [1] , [2] . Detailed history of animal exposure should be taken when suspected.…”