Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative bacilli.
Infected animals may excrete Brucella spp, in their milk for prolonged periods and human infection is acquired by ingesting contaminated dairy products (especially unpasteurised milk), uncooked meat or offal.
Animal urine, faeces, vaginal discharge and uterine products may transmit infection through abraded skin or via splashes and aerosols to the respiratory tract and conjunctiva.
Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative bacilli.
Infected animals may excrete Brucella spp, in their milk for prolonged periods and human infection is acquired by ingesting contaminated dairy products (especially unpasteurised milk), uncooked meat or offal.
Animal urine, faeces, vaginal discharge and uterine products may transmit infection through abraded skin or via splashes and aerosols to the respiratory tract and conjunctiva.
Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative bacilli.
Infected animals may excrete Brucella spp, in their milk for prolonged periods and human infection is acquired by ingesting contaminated dairy products (especially unpasteurised milk), uncooked meat or offal.
Animal urine, faeces, vaginal discharge and uterine products may transmit infection through abraded skin or via splashes and aerosols to the respiratory tract and conjunctiva.
Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative bacilli.
Infected animals may excrete Brucella spp, in their milk for prolonged periods and human infection is acquired by ingesting contaminated dairy products (especially unpasteurised milk), uncooked meat or offal.
Animal urine, faeces, vaginal discharge and uterine products may transmit infection through abraded skin or via splashes and aerosols to the respiratory tract and conjunctiva.
Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative bacilli.
Infected animals may excrete Brucella spp, in their milk for prolonged periods and human infection is acquired by ingesting contaminated dairy products (especially unpasteurised milk), uncooked meat or offal.
Animal urine, faeces, vaginal discharge and uterine products may transmit infection through abraded skin or via splashes and aerosols to the respiratory tract and conjunctiva.
2. Introduction
■ Brucellosis is an enzootic infection (i.e. endemic in animal) caused by Gram-negative
bacilli.
■ The four species causing human disease and their animal hosts are:
1. Brucella melitensis (goats sheep and camels in Europe, especially the Mediterranean
basin, the Middle East,Africa, India, Central Asia and South America. B. melitensis
causes the most severe disease.
2. B. abortus (cattle, mainly in Africa,Asia and South America).
3. B. suis (pigs in South Asia) often associated with abscess formation.
4. B. can's (dogs).
3. Introduction
■ Infected animals may excrete Brucella spp, in their milk for prolonged
periods and human infection is acquired by ingesting contaminated
dairy products (especially unpasteurised milk), uncooked meat or offal.
■ Animal urine, faeces, vaginal discharge and uterine products may
transmit infection through abraded skin or via splashes and aerosols to
the respiratory tract and conjunctiva.
4.
5. Clinical features
■ Brucella spp. are intracellular organisms that survive for long periods within the reticulo-
endothelial system.
■ This explains the disease chronicity and tendency to relapse, even after antimicrobial
therapy.
■ Acute illness is characterised by a high swinging temperature, rigors, lethargy, headache,
joint and muscle pains, and scrotal pain.
■ Occasionally, there is delirium, abdominal pain and constipation.
■ Physical signs are non-specific, sig. enlarged lymph nodes.
■ Splenomegaly may cause thrombocytopenia.
■ Localised infection, which occurs in about 30% of patients, is more likely if diagnosis and
treatment are delayed.
6.
7. Diagnosis
1. Definitive diagnosis depends on culture of the organism.
2. Blood cultures are positive in 75-80% of B. melitensis and 50% of B. abortus infections.
3. Bone marrow culture is not routine but may increase the diagnostic yield if antibiotics
have been used prior to culture.
4. CSF culture in neurobrucellosis is Positive in about 30% of cases.
5. The laboratory should be alerted to a suspected diagnosis of brucellosis, as the organism
may infect laboratory workers and must be cultured at the appropriate biosafety level.
6. Serology may also aid diagnosis.
7. In endemic areas, a single high antibody titre of more than 1/320 or a fourfold rise in titre
is needed to support a diagnosis of acute infection.The test usually takes several weeks to
become positive but should eventually detect 95% of acute infections.
8. Management
1. Adults with non-localised disease
■ Doxycycline 100 mg twice daily orally for 6 weeks plus gentamicin 5 mg/kg IV once daily for 7 days.
or
■ Doxycycline 100 mg twice daily plus rifampicin 600-900 mg orally once daily for 6 weeks.
2. Bone disease
■ Doxycycline 100 mg twice daily plus rifampicin 600-900 mg once daily orally for 6 weeks plus
gentamicin 5 mg/kg IV once daily for 7 days.
or
■ Ciprofloxacin 750 mg twice daily orally plus rifampicin 600-900 mg orally once daily for 3 months.
9. Management
3. Neurobrucellosis
■ Doxycycline 100 mg twice daily plus rifampicin 600-900 mg orally once daily for 6 weeks plus
ceftriaxone 2vg IV twice daily until the cerebrospinal fluid is clear (though susceptibility should be
confirmed because sensitivity to third-generation cephalosporins varies among strains).
4. Endocarditis
■ Almost always needs surgical intervention.
plus
■ Doxycycline 100 mg twice daily, rifampicin 600-900 mg orally once daily and co-trimoxazole 5 mg/kg
of trimethoprim component for 6 months plus gentamicin 5 mg/kg IV once daily for 2-4 weeks.
5. Pregnancy
■ Rifampicin 600-900 mg orally once daily and co-trimoxazole 5 mg/ kg of trimethoprim component for
4 weeks, but caution in last week of pregnancy due to displacement of bilirubin from albumin by
drugs and risk of kernicterus to the fetus.
