Microbiology
Summary
Campylobacter jejuni is a curved, gram-negative, oxidase-positive rod. It is thermophilic and prefers to grow in temperatures around 42¬°C. The main reservoir for Campylobacter is the intestinal tract of animals, especially poultry, and transmission occurs through the fecal-oral route during the slaughtering process.
Infection with Campylobacter can lead to symptoms such as bloody diarrhea and possible bacteremia, as the bacterium is invasive, penetrating the gut mucosa and entering the bloodstream. One potential complication of a Campylobacter infection is reactive arthritis (Reiter's syndrome), a seronegative spondyloarthropathy. Another rare but testable complication of Campylobacter infections is Guillain-Barr≈Ω Syndrome, an autoimmune response causing demyelination of peripheral nerves and resulting in an ascending paralysis.
Lesson Outline
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FAQs
Campylobacter jejuni is a common cause of gastroenteritis, which is an inflammation of the gastrointestinal tract involving the stomach and small intestine. The infection usually manifests as diarrhea, abdominal pain, cramping, nausea, and sometimes fever. It often results from the consumption of contaminated food or water, particularly poultry, which acts as a reservoir for the bacteria.
Guillain-Barr≈Ω Syndrome (GBS) is a rare neurological disorder in which the body's immune system attacks the peripheral nervous system. In some cases, GBS has been associated with a preceding Campylobacter jejuni infection. About 30% of GBS cases worldwide are thought to result from the immune system's abnormal response to a C. jejuni infection, leading to damage to nerves and their protective covering called myelin sheath.
As a thermophilic bacterium, C. jejuni thrives at higher temperatures. Optimal growth occurs at 42¬°C, which is the body temperature of birds, particularly poultry. This attribute makes C. jejuni one of the most common foodborne pathogens, especially through undercooked chicken, as well as through cross-contamination in the kitchen.
Fecal-oral transmission plays a significant role in the spread of Campylobacter jejuni. The bacterium is commonly found in the intestines of animals, particularly poultry. Contaminated fecal matter containing the bacteria may contaminate food or water sources, leading to ingestion by humans. Inadequate cooking or handling of contaminated food can result in infection, causing symptoms such as diarrhea, bloody stool, and abdominal cramps.
Reactive arthritis is a condition where the body's immune system reacts to an infection in another part of the body, causing inflammation in the joints. It has been reported that some people develop reactive arthritis after a Campylobacter jejuni infection. This autoimmune response can result in symptoms such as joint pain, swelling, and stiffness, typically affecting the knees, ankles, and feet. The onset of reactive arthritis may appear several weeks after the initial C. jejuni infection.