Cox’s Conference: Brucellosis with spondylitis and endocarditis

In today’s Cox’s Conference, Dr. Jessy Barnes presented a case of disseminated brucellosis to expert discussant, Dr. James Luby. Case highlights and pearls are summarized below. 

Case:

The patient is a 59 year old Hispanic woman with non-insulin dependent type 2 diabetes mellitus and hypertension who presented to clinic with 3 months of daily fevers, night sweats, chills, and low back pain. She moved to the United States from Mexico where she was noted to regularly consume unpasteurized cheese, goat milk, and cow’s milk. Her brother was recently diagnosed with Brucellosis, prompting earlier suspicion for Brucellosis. Serologies and cultures for Brucella were positive for Brucella melitensis. She was treated with rifampin and doxycycline and discharged on a prolonged regimen. However, her outpatient course was complicated significant antibiotic nonadherence.

On follow up in infectious disease clinic, she was found to have a new diastolic murmur. Transesophageal echocardiography demonstrated new aortic insufficiency and a thickened aortic valve concerning for Brucella endocarditis. She is currently continuing treatment.

Discussion:

Brucellosis is a zoonotic infection transmitted through the food products (classically unpasteurized milk or milk products) of infected animals (cows, pigs, goats, livestock). The diagnosis is difficult due to its initial presentation being marked by non-specific constitutional symptoms. These include:

  • fever
  • fatigue
  • night sweats
  • weight loss
  • pain
  • anorexia
  • headaches
Epidemiology

The distribution of Brucellosis cases as of 2006 are shown below. In North America, Mexico remains a notable reservoir. In the United States, nearly 80% of patients with Brucellosis were of Hispanic origin. Of note, there has been an increased number of cases in Texas over this past year.

brucella world map
Lancet Infect Dis. 2006 Feb;6(2):91-9.
brucella US
Lancet Infect Dis. 2006 Feb;6(2):91-9.

 

Exposure Risks:
  • travel to an endemic region
  • consumption of unpasteurized milk products or exposure to livestock
  • occupation: slaughterhouse workers, meat-packing workers, veterinarians, laboratory workers, farmers, hunters of wild game animals (feral swine are known reservoir in the U.S.)
Multi-systemic Presentation:

Acute brucellosis can affect virtually any organ system. In our patient, her course was complicated by both spondylitis and endocarditis, due in part to treatment nonadherence.

  • MSK: spondylitis
  • Cardiovascular: endocarditis, pericarditis, myocarditis, enarteritis
  • Neurologic: meningitis, encephalitis, myelitis, neuritis
  • Gastrointestinal: hepatitis, abscess, colitis, ileitis, peritonitis, pancreatitis
  • Genitourinary: orchitis, epididymitis
  • Heme: cytopenias and DIC
  • Pulmonary: bronchitis, pneumoitis, pneumonia
  • Ophthalmic: uveitis
Chronic Brucellosis:

Manifestations of disease lasting longer than year is considered chronic brucellosis. Even in the absence of local symptoms, it is not uncommon for patients to have persistent chronic fatigue syndrome, depression, arthralgias, and night sweats.

Treatment:

Treatment is typically prolonged, usually with doxycycline as the backbone of therapy. This is often combined with rifampin, streptomycin, or gentamicin. Alternative agents include fluoroquinolones or bactrim.

Of note, the Jarisch-Herxheimer reaction is a known complication of treatment of Brucella.