Brucellosis Sung Chul Hwang, M.D. Dept of Pulmonary and Critical Care Medicine Ajou University School of Medicine

Introduction Also called undulant, Mediteranean, or Malta fever Zoonotic infection Four species : abortus(cattle) melitensis (goats and sheep) suis(swine) canis(dogs)

Febrile patterns of Brucellosis(Undulant fever)

Epidemiology Direct inoculation through cuts and abrasions Via conjunctiva Inhalation of aerosols Ingestion of contaminated food Venereal transmission has been suggested

Pathogenesis Invasion of body  phagocytized by PMN or Macrophages  spread to regional L/Ns  Blood stream  formation of granulomas with epitheloid cells, giant cells, lymphocytes and plasma cells in liver and RES

Acute Brucellosis Incubation 7 to 21 days to months Insidious onset of low grade fever, and no localizing complaints Anorexia, sweats, chills, weight loss, headache, backache, arthralgia Multiple complaints but a few physical findings Splenomegally (10-20%), lymphadenopathy(15%), hepatomegaly(10%)

Localized Brucellosis Any anatomic locations Osteomyelitis, splenic abscess, GU tract infections, pulmonary infection, endocarditis(most common cause of mortality)

Chronic Brucellosis Malaise asthenia, depression, chronic fatigue syndrome- like presentation Ill health of more than 1 year of following onset Brucellosis Mixed manifestations: 1)relapsing illness with or without localizing infection, 2)patients with no objective signs of infections, 3)no evidence of active Brucellosis by serology or culture

Diagnosis Clinical suspicion in chronic fever and non-specific complaints Routine Lab. and X-rays : non-specific Cultures: Blood, Bone Marrow, or liver biopsy in initial stage, but only 15 to 20% positive  slow growth  biphasic media (Ruiz-Castaneda) : 7 – 21 days to 35 days but usually Bactec culture system only grow it for 7 days then discard

Serologic Tests for Brucellosis Serum Agglutination ( Standard Tube Assay) : > 1: 160 or 4 fold increased titer Complement fixation Rose Bengal Agglutination Antibrucella Coombs ELISA

Treatment of Brucellosis Choice : Tetracycline 30 mg/kg/day gor 3 to 6 weeks + SM 15mg/kg q 12hrs for first 2 weeks Alternative : Tetracycline (or doxycycline plus GM or Rifampin Endocarditis : Antibiotics + Valve replacement

Prognosis Mortality < 5 % < 2 % with antibiotics Endocarditis is the most common cause of Mortality

Prevention Immunization of animals with live attenuated vaccine No vaccine available for human Pasteurization of the milk products Avoid contacts and exposure by protective garments and gloves