INITIAL SYMPTOMS:
Irregular fever with sweating, headache, arthralgias, myalgias, weakness, fatigue, and weight loss; [CCDM, p. 78];
FINDINGS:
Patients recover in 2-3 weeks in uncomplicated cases. The three forms are acute (<8 weeks), undulant (<1 year), and chronic (>1 year). Arthralgias are common in all forms. Both infectious and reactive arthritides occur. Bone involvement is also common. About 3% to 15% of patients have spondylitis, usually of the lumbar spine. Less than 1/3 of patients have lymphadenopathy and hepatosplenomegaly. Abnormal liver function tests are common in acute and undulant brucellosis. Gastrointestinal symptoms occur in up to 70% of patients. Anemia, leukopenia, and thrombocytopenia are common in the undulant form. Patients in endemic areas may have constipation. Travelers are more likely to present with diarrhea. Respiratory findings are rare. [ID, p. 164, 1362, 1717-20; PPID, p. 2584-8; Guerrant, p. 271-5; Merck Manual, p. 1246-7; Cohen, p. 1240] Two stockbreeders presented with high fever and severe exudative pharyngitis. [
PMID 18397911] About 1/2 of patients have myalgia and difficulty walking. A maculopapular rash is an uncommon finding. [Harrison ID, p. 593-4] See "Arthritis, reactive."
COMPLICATIONS:
The chronic form affects mainly older individuals and includes depression, eye disease, and CNS infections. About 10% of infected men develop epididymitis and/or orchitis. Endocarditis, usually involving the aortic valve, has been reported as one of the common causes of death in patients with brucellosis. Myocarditis and pericarditis are complications. Brucella is a common cause of uveitis in endemic areas. Neurobrucellosis (meningitis, encephalitis, brain abscess, myelitis, radiculitis, and neuritis) affects approximately 2% to 5% of patients. Guillain-Barre syndrome has been reported. Pancreatitis is rare. About 5% of patients have skin lesions including papules, ulcers, petechiae, and erythema nodosum. Chronic brucellosis is associated with hypergammaglobulinemia. [ID, p. 164, 1362, 1717-20; PPID, p. 2584-8; Guerrant, p. 271-5; Merck Manual, p. 1246-7; Cohen, p. 1240]
EPIDEMIOLOGY:
Brucellosis is a generalized bacterial infection characterized by irregular fever (undulant fever). It is an occupational disease for workers who handle infected animals and their tissues. Affected workers include farmers, hunters, veterinarians, butchers, and slaughterers. Airborne transmission occurs in animal stables and pens, slaughterhouses, and medical laboratories. A vaccine to prevent the disease in animals is available. Infections have been reported in cattle, swine, goats, sheep, dogs, coyotes, bison, elk, caribou, and deer. Transmission by raw milk and cheese and by contaminated meat has been reported. [CCDM, p. 78-80; Foodborne Illnesses. CDC. 4/16/04; ID, p. 1717] Humans may acquire infections from infected chickens or desert rats. [Merck Manual, p. 1246] There are reports of sexually transmitted brucellosis. [Cecil, p. 1891]
For updated text and symptoms of infectious diseases, see iddx.com.