Brucellosis (Mediterranean Fever) | Transmission, Pathogenesis, Symptoms, Diagnosis, Treatment

Summary

Brucellosis is a zoonotic infection caused by *Brucella* bacteria, primarily affecting animals and transmitted to humans through animal contact, unpasteurized dairy, or contaminated bodily fluids. The disease is globally widespread and impacts all age groups and genders equally. Symptoms include fever, night sweats with a moldy odor, malaise, weight loss, and joint pain, often making diagnosis challenging. Diagnosis involves culturing the bacteria or detecting antibodies through serology. Treatment varies, with doxycycline for non-pregnant individuals and rifampin for pregnant patients. Brucellosis is preventable by avoiding exposure to infected animals and unpasteurized products.

Takeaways

• 😀 Brucellosis is a zoonotic infection caused by bacteria of the genus *Brucella*, primarily affecting humans who come into contact with infected animals or their bodily fluids.
• 😀 This disease is also known as Malta fever and Mediterranean fever, and it is caused by four species of *Brucella* that can infect humans.
• 😀 Brucellosis is widespread globally, particularly in regions like the Mediterranean, Sub-Saharan Africa, the Middle East, Central Asia, South Asia, China, and South America.
• 😀 It is the most common zoonotic disease in the world, affecting all age groups and genders equally.
• 😀 The main sources of transmission include direct contact with animals (e.g., cattle, goats, sheep, pigs, camels, dogs), consumption of unpasteurized dairy products, and exposure to contaminated bodily fluids.
• 😀 Drinking unpasteurized milk is the most common risk factor for acquiring brucellosis, while exposure to animal tissues, especially during birth, is also a significant risk.
• 😀 The bacteria enter the body through the gastrointestinal tract, are engulfed by macrophages, and then travel to the lymphatic system, where they can persist for weeks or even months.
• 😀 Symptoms often begin with constitutional signs like fever, night sweats (with a distinctive moldy odor), malaise, and weight loss. These symptoms can resemble other infections or conditions.
• 😀 Physical signs of brucellosis can include hepatosplenomegaly (enlarged liver and spleen) and lymphadenopathy (enlarged, tender lymph nodes).
• 😀 Diagnosis is made through bacterial culture or serology, with a fourfold increase in antibody titers between the acute and convalescent phases being a key diagnostic marker.
• 😀 Treatment varies by patient group; non-pregnant adults are typically treated with doxycycline, often combined with gentamicin or Septra, while pregnant patients are treated with rifampin, sometimes with Septra.

Q & A

What is brucellosis and what causes it?

Brucellosis is a zoonotic infection caused by bacteria of the genus *Brucella*. It primarily affects animals but can also infect humans through various means of transmission.

Where is brucellosis most commonly found?

Brucellosis is found worldwide, with endemic areas including the Mediterranean, Sub-Saharan Africa, the Middle East, Central Asia, South Asia, China, and Central and South America.

How is brucellosis transmitted?

Brucellosis is transmitted through contact with infected animals (such as cattle, goats, sheep, pigs, camels, and dogs), ingestion of unpasteurized dairy products, or exposure to contaminated bodily fluids.

What are the primary risk factors for contracting brucellosis?

The primary risk factors include direct contact with infected animals, handling animal tissues or fluids, and consuming unpasteurized dairy products.

What is the incubation period for brucellosis?

The incubation period for brucellosis typically ranges from 2 to 4 weeks but can vary from a few days to several months.

What are the common clinical symptoms of brucellosis?

Common symptoms include fever, night sweats (with a moldy odor), malaise, weight loss, headache, joint pain, abdominal pain, indigestion, cough, and depression.

What physical signs may be present in individuals with brucellosis?

Physical signs can include hepatosplenomegaly (enlarged liver and spleen) and lymphadenopathy (swollen and tender lymph nodes).

How is brucellosis diagnosed?

Brucellosis is diagnosed through culture of the *Brucella* bacteria or through serology testing for antibody titers. A fourfold increase in antibody titers between the acute and convalescent phases is an important diagnostic indicator.

What is the typical treatment for brucellosis in non-pregnant patients?

Non-pregnant patients are typically treated with doxycycline, often in combination with gentamicin or septra.

How is brucellosis treated in pregnant patients or children?

In pregnant patients or children, doxycycline is avoided. Treatment usually involves rifampin with or without septra.