The mainstay of treatment includes combinations of antibiotics to cure symptoms and prevent relapse. Treatment adherence is the cornerstone of a successful outcome, as relapse is largely due to poor antibiotic compliance, and should be encouraged at every opportunity.
Uncomplicated disease
Brucellosis is considered uncomplicated if there are acute nonspecific features in the absence of focal infection. Antibiotic therapy shortens the duration of illness and relieves symptoms.[75]World Health Organization. Brucellosis in humans and animals. 2006 [internet publication].
https://www.who.int/publications/i/item/9789241547130
Up to 30% of patients treated with monotherapy experience relapses, and therefore a combination of antibiotics is routinely recommended. However, relapse is not actually related to emergence of antimicrobial resistance but rather to poor antibiotic compliance, and usually occurs within 6 months of completion of therapy.[41]Beeching NJ. Brucellosis. In Fauci AS, Braunwald E, Kasper DL, et al., eds. Harrison’s principles of internal medicine. 20th ed. New York, NY: McGraw-Hill; 2018:1192-6.[42]Beeching NJ, Madkour MM. Brucellosis. In: Farrar J, Hotez P, Junghanss T, et al, eds. Manson’s tropical diseases. 23rd ed. London: Elsevier; 2013:371-378, 378.e1.[128]Ariza J, Bosilkovski M, Cascio A, et al. Perspectives for the treatment of brucellosis in the 21st century: the Ioannina recommendations. PLoS Med. 2007 Dec;4(12):e317.
http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0040317
http://www.ncbi.nlm.nih.gov/pubmed/18162038?tool=bestpractice.com
The World Health Organization (WHO) recommends that adults and children aged ≥8 years should be treated with a tetracycline for 6 weeks (doxycycline is preferred due to its less frequent dose schedule and lower risk of adverse effects), plus either a parenteral aminoglycoside (streptomycin for 2-3 weeks or gentamicin for 7-10 days) or oral rifampin for 6 weeks.[75]World Health Organization. Brucellosis in humans and animals. 2006 [internet publication].
https://www.who.int/publications/i/item/9789241547130
The Centers for Disease Control and Prevention (CDC) recommend an oral regimen for uncomplicated disease (a tetracycline or trimethoprim/sulfamethoxazole plus rifampin for a minimum of 6 weeks).[63]Centers for Disease Control and Prevention. Brucellosis reference guide: exposures, testing and prevention. February 2017 [internet publication].
https://www.cdc.gov/brucellosis/pdf/brucellosi-reference-guide.pdf
Tetracyclines are generally contraindicated in children aged <8 years due to the risk of tooth discoloration and inhibition of bone growth. Therefore, tetracyclines can be replaced by trimethoprim/sulfamethoxazole in children aged <8 years. The WHO recommends trimethoprim/sulfamethoxazole for 6 weeks, plus either an aminoglycoside (streptomycin for 3 weeks or gentamicin for 7-10 days) or rifampin for 6 weeks.[75]World Health Organization. Brucellosis in humans and animals. 2006 [internet publication].
https://www.who.int/publications/i/item/9789241547130
The CDC recommend an oral regimen for uncomplicated disease (trimethoprim/sulfamethoxazole plus rifampin for 4-6 weeks).[63]Centers for Disease Control and Prevention. Brucellosis reference guide: exposures, testing and prevention. February 2017 [internet publication].
https://www.cdc.gov/brucellosis/pdf/brucellosi-reference-guide.pdf
Tetracyclines are contraindicated in pregnant women. Optimum treatment of pregnant and breast-feeding women is based on anecdotal reports.[58]Khan MY, Mah WM, Memish ZA. Brucellosis in pregnant women. Clin Infect Dis. 2001 Apr 15;32(8):1172-7.
http://cid.oxfordjournals.org/content/32/8/1172.full
http://www.ncbi.nlm.nih.gov/pubmed/11283806?tool=bestpractice.com
A 6-week course of oral rifampin is generally recommended.[41]Beeching NJ. Brucellosis. In Fauci AS, Braunwald E, Kasper DL, et al., eds. Harrison’s principles of internal medicine. 20th ed. New York, NY: McGraw-Hill; 2018:1192-6.[42]Beeching NJ, Madkour MM. Brucellosis. In: Farrar J, Hotez P, Junghanss T, et al, eds. Manson’s tropical diseases. 23rd ed. London: Elsevier; 2013:371-378, 378.e1.[75]World Health Organization. Brucellosis in humans and animals. 2006 [internet publication].
https://www.who.int/publications/i/item/9789241547130
Rifampin plus trimethoprim/sulfamethoxazole for 4 weeks is an acceptable alternative.[58]Khan MY, Mah WM, Memish ZA. Brucellosis in pregnant women. Clin Infect Dis. 2001 Apr 15;32(8):1172-7.
http://cid.oxfordjournals.org/content/32/8/1172.full
http://www.ncbi.nlm.nih.gov/pubmed/11283806?tool=bestpractice.com
A specialist should be consulted for guidance on antibiotic selection in these patients.
Optimum regimens remain controversial, but the following principles are becoming clearer.[128]Ariza J, Bosilkovski M, Cascio A, et al. Perspectives for the treatment of brucellosis in the 21st century: the Ioannina recommendations. PLoS Med. 2007 Dec;4(12):e317.
http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0040317
http://www.ncbi.nlm.nih.gov/pubmed/18162038?tool=bestpractice.com
[129]Skalsky K, Yahav D, Bishara J, et al. Treatment of human brucellosis: systematic review and meta-analysis of randomised controlled trials. BMJ. 2008 Mar 29;336(7646):701-4.
http://www.bmj.com/content/336/7646/701
http://www.ncbi.nlm.nih.gov/pubmed/18321957?tool=bestpractice.com
[130]Solís García del Pozo J, Solera J. Systematic review and meta-analysis of randomized clinical trials in the treatment of human brucellosis. PLoS One. 2012;7(2):e32090.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032090
http://www.ncbi.nlm.nih.gov/pubmed/22393379?tool=bestpractice.com
[131]Yousefi-Nooraie R, Mortaz-Hejri S, Mehrani M, et al. Antibiotics for treating human brucellosis. Cochrane Database Syst Rev. 2012 Oct 17;10:CD007179.
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007179.pub2/full
http://www.ncbi.nlm.nih.gov/pubmed/23076931?tool=bestpractice.com
[132]Hashemi SH, Gachkar L, Keramat F, et al. Comparison of doxycycline-streptomycin, doxycycline-rifampin, and ofloxacin-rifampin in the treatment of brucellosis: a randomized clinical trial. Int J Infect Dis. 2012 Apr;16(4):e247-51.
http://www.ncbi.nlm.nih.gov/pubmed/22296864?tool=bestpractice.com
Regimens containing an injectable aminoglycoside are superior to those with two oral agents, mainly in reducing subsequent relapse.
6 weeks of oral therapy is superior to 4 weeks.
Fluoroquinolones are probably not suitable for inclusion in first-line regimens due to reduced efficacy compared with the above, and are not usually recommended. However, a fluoroquinolone plus rifampin is better tolerated than doxycycline plus rifampin.
Triple-therapy regimens (including an aminoglycoside) are probably superior to double antimicrobial regimens, and may be preferred in complicated disease.[128]Ariza J, Bosilkovski M, Cascio A, et al. Perspectives for the treatment of brucellosis in the 21st century: the Ioannina recommendations. PLoS Med. 2007 Dec;4(12):e317.
http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0040317
http://www.ncbi.nlm.nih.gov/pubmed/18162038?tool=bestpractice.com
[129]Skalsky K, Yahav D, Bishara J, et al. Treatment of human brucellosis: systematic review and meta-analysis of randomised controlled trials. BMJ. 2008 Mar 29;336(7646):701-4.
http://www.bmj.com/content/336/7646/701
http://www.ncbi.nlm.nih.gov/pubmed/18321957?tool=bestpractice.com
[130]Solís García del Pozo J, Solera J. Systematic review and meta-analysis of randomized clinical trials in the treatment of human brucellosis. PLoS One. 2012;7(2):e32090.
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032090
http://www.ncbi.nlm.nih.gov/pubmed/22393379?tool=bestpractice.com
[131]Yousefi-Nooraie R, Mortaz-Hejri S, Mehrani M, et al. Antibiotics for treating human brucellosis. Cochrane Database Syst Rev. 2012 Oct 17;10:CD007179.
http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD007179.pub2/full
http://www.ncbi.nlm.nih.gov/pubmed/23076931?tool=bestpractice.com
[133]Pappas G, Christou L, Akritidis N, et al. Quinolones for brucellosis: treating old diseases with new drugs. Clin Microbiol Infect. 2006 Sep;12(9):823-5.
http://www.ncbi.nlm.nih.gov/pubmed/16882286?tool=bestpractice.com
[134]Bosilkovski M, Kirova V, Grozdanovski K, et al. Doxycycline-rifampin versus doxycycline-rifampin-gentamicin in treatment of human brucellosis. Trop Doct. 2012 Jan;42(1):13-7.
http://www.ncbi.nlm.nih.gov/pubmed/22290107?tool=bestpractice.com
[135]Vrioni G, Bourdakis A, Pappas G, et al. Administration of a triple versus a standard double antimicrobial regimen for human brucellosis more efficiently eliminates bacterial DNA load. Antimicrob Agents Chemother. 2014 Dec;58(12):7541-4.
http://aac.asm.org/content/58/12/7541.full
http://www.ncbi.nlm.nih.gov/pubmed/25246401?tool=bestpractice.com
Regimens incorporating injectable drugs have the advantage that adherence can be confirmed due to daily attendance at a healthcare facility. However, disadvantages include the need for daily attendance at a healthcare facility (or inpatient management), and the possibility of irreversible 8th cranial nerve toxicity, which may occur late as an adverse effect of aminoglycoside administration.
Relapses are usually treated with the same regimen as initially used, as resistance to antimicrobials is rarely the cause. However, most clinicians would use a regimen containing an aminoglycoside for relapses, especially if an aminoglycoside had not been included in the initial regimen.
Complicated disease
Focal disease (orchitis, sacroiliitis, spondylitis, endocarditis, meningoencephalitis, focal brain or cranial nerve lesions) usually requires longer periods of treatment. Most treatment failures are associated with poor compliance, and, therefore, this is a major issue with prolonged courses of antibiotics. There is little evidence regarding optimum duration of treatment in cases of focal disease, but most authors favor triple antibiotic therapy for adults or adolescents, with an injectable aminoglycoside continued for 2 weeks combined with doxycycline and rifampin, which are continued for at least 3-6 months.[41]Beeching NJ. Brucellosis. In Fauci AS, Braunwald E, Kasper DL, et al., eds. Harrison’s principles of internal medicine. 20th ed. New York, NY: McGraw-Hill; 2018:1192-6.[42]Beeching NJ, Madkour MM. Brucellosis. In: Farrar J, Hotez P, Junghanss T, et al, eds. Manson’s tropical diseases. 23rd ed. London: Elsevier; 2013:371-378, 378.e1.[75]World Health Organization. Brucellosis in humans and animals. 2006 [internet publication].
https://www.who.int/publications/i/item/9789241547130
[128]Ariza J, Bosilkovski M, Cascio A, et al. Perspectives for the treatment of brucellosis in the 21st century: the Ioannina recommendations. PLoS Med. 2007 Dec;4(12):e317.
http://journals.plos.org/plosmedicine/article?id=10.1371/journal.pmed.0040317
http://www.ncbi.nlm.nih.gov/pubmed/18162038?tool=bestpractice.com
[129]Skalsky K, Yahav D, Bishara J, et al. Treatment of human brucellosis: systematic review and meta-analysis of randomised controlled trials. BMJ. 2008 Mar 29;336(7646):701-4.
http://www.bmj.com/content/336/7646/701
http://www.ncbi.nlm.nih.gov/pubmed/18321957?tool=bestpractice.com
Most patients with infective endocarditis end up needing valve replacement despite 6 months or more of antibiotic treatment.[5]Pappas G, Papadimitriou P, Akritidis N, et al. The new global map of human brucellosis. Lancet Infect Dis. 2006 Feb;6(2):91-9.
http://www.ncbi.nlm.nih.gov/pubmed/16439329?tool=bestpractice.com
[41]Beeching NJ. Brucellosis. In Fauci AS, Braunwald E, Kasper DL, et al., eds. Harrison’s principles of internal medicine. 20th ed. New York, NY: McGraw-Hill; 2018:1192-6. There is evidence that early surgery improves mortality.[136]Keshtkar-Jahromi M, Razavi SM, Gholamin S, et al. Medical versus medical and surgical treatment for brucella endocarditis. Ann Thorac Surg. 2012 Dec;94(6):2141-6.
http://www.ncbi.nlm.nih.gov/pubmed/23102495?tool=bestpractice.com
In cases of neurologic manifestations, streptomycin or gentamicin use is usually discouraged because of questionable ability of aminoglycosides to penetrate the cerebrospinal fluid and the potential for neurotoxicity, which may further complicate the clinical presentation.[137]Pappas G, Akritidis N, Christou L. Treatment of neurobrucellosis: what is known and what remains to be answered. Expert Rev Anti Infect Ther. 2007 Dec;5(6):983-90.
http://www.ncbi.nlm.nih.gov/pubmed/18039082?tool=bestpractice.com
Ceftriaxone or trimethoprim/sulfamethoxazole may be added as a third drug for better central nervous system penetration.[41]Beeching NJ. Brucellosis. In Fauci AS, Braunwald E, Kasper DL, et al., eds. Harrison’s principles of internal medicine. 20th ed. New York, NY: McGraw-Hill; 2018:1192-6.[42]Beeching NJ, Madkour MM. Brucellosis. In: Farrar J, Hotez P, Junghanss T, et al, eds. Manson’s tropical diseases. 23rd ed. London: Elsevier; 2013:371-378, 378.e1.[48]Beeching NJ, Erdem H. Brucellosis. In: Cohen J, Powderly WG, Opal SM, eds. Infectious diseases. 4th ed. London: Elsevier Science; 2016:1098-1101.[137]Pappas G, Akritidis N, Christou L. Treatment of neurobrucellosis: what is known and what remains to be answered. Expert Rev Anti Infect Ther. 2007 Dec;5(6):983-90.
http://www.ncbi.nlm.nih.gov/pubmed/18039082?tool=bestpractice.com
[138]Erdem H, Ulu-Kilic A, Kilic S, et al. Efficacy and tolerability of antibiotic combinations in neurobrucellosis: results of the Istanbul study. Antimicrob Agents Chemother. 2012 Mar;56(3):1523-8.
http://aac.asm.org/content/56/3/1523.long
http://www.ncbi.nlm.nih.gov/pubmed/22155822?tool=bestpractice.com
[139]Tajerian A, Sofian M, Zarinfar N, et al. Manifestations, complications, and treatment of neurobrucellosis: a systematic review and meta-analysis. Int J Neurosci. 2022 Aug 5 [Epub ahead of print].
https://www.doi.org/10.1080/00207454.2022.2100776
http://www.ncbi.nlm.nih.gov/pubmed/35930502?tool=bestpractice.com
A triple antibiotic regimen is generally recommended for complicated infection, and courses may need to be prolonged for longer periods of time according to clinical and radiologic response.[140]Ulu-Kilic A, Karakas A, Erdem H, et al. Update on treatment options for spinal brucellosis. Clin Microbiol Infect. 2014 Feb;20(2):O75-82.
http://www.ncbi.nlm.nih.gov/pubmed/24118178?tool=bestpractice.com
In the absence of evidence (regarding treatment of focal disease with or without neurologic manifestations), similar considerations may apply for children, and should be evaluated on an individual basis for pregnant or breast-feeding women. Consultation with an infectious-diseases specialist is, therefore, advised before commencing treatment in pregnant or breast-feeding women and in children.
Relapses are usually treated with the same regimen as initially used, as resistance to antimicrobials is rarely the cause.