Brucella species, mainly infect cattle, swine, goats, sheep and dogs. Most cases are caused by ingesting unpasteurized milk or cheese from infected goats or sheep.
About
- Intracellular bacteria only 4 are pathogenic
- Zoonosis. Human-to-human transmission is very rare.
Microbiology
- B. melitensis (goats, sheep and camels): most severe disease.
- B. abortus (cattle). B. suis (pigs) B. canis (dogs).
Clinical
- IP is 1 week to 4 weeks
- From infected animal : milk, cheese, yoghurt, butter, uncooked meat, respiratory
- Pyrexia, rigors, sweating, lethargy, headache
- Joint and muscle pains. Delirium, abdominal pain and constipation
- Suppurative arthritis, synovitis, bursitis; spinal spondylitis;
osteomyelitis; paravertebral or psoas abscess
- CNS Meningitis; stroke; cranial nerve palsies; myelopathy;
intracranial or subarachnoid haemorrhage; radiculopathy
- Ocular Uveitis; retinal thrombophlebitis
- Cardiac Myocarditis; endocarditis
- Respiratory Pneumonitis; lung abscess; hilar adenopathy
- Abdominal Splenic abscess or calcification, hepatitis, orchitis
Investigations
- Blood cultures: prolonged incubation may be required. B. melitensis
is the most readily cultured species.
- CSF in CNS disease
- Serology: a single titre of > 1/320 or a x4 rise in antibody
Management
- Aminoglycosides with tetracyclines when
used against brucellae: Doxycycline 100 mg BD 6 weeks + IV Gentamicin for 7 days. Streptomycin is also used.
- Add Rifampicin if bone involvement
- Add Ceftriaxone if there is neurobrucellosis.
- Children: trimethoprim/sulfamethoxazole (co-trimoxazole) combined with an aminoglycoside (streptomycin, gentamycin) or rifampicin.
References