infectious diseases
Anthrax
Treatment of Anthrax
Antibiotics Other medications Pleural fluid drainage If treatment of anthrax is delayed (usually because the diagnosis is missed), the risk of death is increased. Cutaneous anthraxwithout significant edema or systemic symptoms or risk of inhalation exposure is treated with one of the following antibiotics for 7 to 10 days: Ciprofloxacin500 mg (10 to 15 mg/kg for children) orally every 12 hours Levofloxacin500 mg orally every 24 hours Moxifloxacin400 mg orally every 24 hours Doxycycline100 mg (2.5 mg/kg for children) orally every 12 hours Amoxicillin1 g every 8 hours may be used if the strain is susceptible to penicillin. Mortality is rare with treatment, but the lesion will progress through the eschar phase. Children and pregnant or breastfeeding women, who typically should not be givenciprofloxacin,levofloxacin,moxifloxacin, ordoxycycline, should nonetheless be given one of these antibiotics to treat anthrax. However, if prolonged treatment is needed, after 14 to 21 days (and if the organism is shown to be susceptible to penicillin), they may be switched toamoxicillin500 mg (15 to 30 mg/kg for children) 3 times a day. Inhalation and other forms of anthrax,including cutaneous anthrax with significant edema or systemic symptoms, require therapy with 3 antibiotics. Antibiotic therapy should include ≥ 2 antibiotics with bactericidal activity, and ≥ 1 should be a protein synthesis inhibitor, which may block toxin production. If theB. anthracisstrain is susceptible to penicillin,penicillin Gis considered equivalent to a fluoroquinolone. Treatment should be given intravenously for ≥ 2 weeks or until the patient is clinically stable, whichever is longer. Once IV combination therapy is completed, therapy should be continued with a single oral antibiotic given for 60 days to prevent relapse resulting from ungerminated spores in the lungs. Appropriate antibiotics with bactericidal activity include A fluoroquinolone (eg,ciprofloxacin400 mg [10 to 15 mg/kg for children] IV every 12 hours,levofloxacin750 mg IV every 24 hours, ormoxifloxacin400 mg IV every 24 hours) A carbapenem (meropenem2 g IV every 8 hours or imipenem 1 g IV every 6 hours) VancomycinIV dosing to maintain serum trough concentration of 15 to 20 mcg/mL (10.4 to 13.8 micromol/L) For penicillin-susceptible strains,penicillin G4 million units IV every 4 hours orampicillin3 g IV every 4 hours Appropriate antibiotics that inhibit protein synthesis include Linezolid600 mg IV every 12 hours Clindamycin900 mg IV every 8 hours Rifampin600 mg every 12 hours Chloramphenicol1 g IV every 6 to 8 hours Linezolidshould be used with caution in patients with myelosuppression; it cannot be used for long periods because of its neurologic side effects. has good central nervous system penetration and has been used to successfully treat anthrax ( Treatment reference ). Rifampin, although not a protein synthesis inhibitor, may be used in this capacity because it has a synergistic effect with the primary antibiotic. Doxycyclineis an alternative protein synthesis inhibitor option iflinezolidorclindamycinis contraindicated or unavailable. Ifmeningitisis suspected,meropenemshould be used with other antibiotics because it has good central nervous system penetration. Ifmeropenemis not available,imipenem/cilastatinis an equivalent alternative. Corticosteroids may be useful for meningitis and severe mediastinal edema but have not been evaluated adequately. Raxibacumab and obiltoxaximab are monoclonal antibodies that bind to the protective antigen component ofB. anthracistoxin and can be used in combination with antibiotics to treat inhalation anthrax. These monoclonal antibodies have shown efficacy in animal models of inhalation anthrax, particularly when given early. IV anthrax human immune globulin prepared from the plasma of donors who have been vaccinated against anthrax can be used in combination with antibiotics to treat inhalation anthrax. manifests inducible beta-lactamases ( Treatment reference ), so single-drug therapy with a penicillin or a cephalosporin is generally not recommended. Patients with inhalation anthrax require supportive care and sometimes mechanical ventilation. Prompt and continuous pleural fluid drainage by chest tube is critical. 1.Hendricks KA, Wright ME, Shadomy SV, et al: Centers for Disease Control and Prevention Expert Panel meetings on prevention and treatment of anthrax in adults.Emerg Infect Dis20(2), 2014. doi: 10.3201/eid2002.130687 