jejuni

Campylobacter jejuni, commonly referred to as C. jejuni, is a Gram-negative, curved- to spiral-shaped bacterium in the family Campylobacteraceae. It is a leading cause of bacterial gastroenteritis worldwide and is primarily associated with animal reservoirs, especially poultry, cattle, and swine. The organism is microaerophilic, grows best under reduced oxygen conditions, and is often cultured at around 42°C to reflect its preference for avian hosts.

Humans acquire C. jejuni mainly by consuming undercooked or contaminated animal products, particularly poultry, or through cross-contamination in the kitchen. Other routes include unpasteurized milk and contaminated water. The incubation period is typically two to five days. Infected individuals commonly experience fever, abdominal cramps, and diarrhea that may be watery or bloody. Most cases are self-limited, but severe disease or complications may require antimicrobial therapy, with azithromycin or other macrolides often preferred over fluoroquinolones in areas with high fluoroquinolone resistance.

Pathogenesis involves colonization and invasion of the intestinal mucosa, contributing to inflammatory diarrhea; toxins may play a lesser role. A notable post-infectious complication is Guillain-Barré syndrome, linked to molecular mimicry between C. jejuni antigens and nerve tissue.

Diagnosis relies on stool culture using selective media, supported by microscopy, antigen testing, or molecular methods. Prevention focuses on proper food handling and cooking, pasteurization, and reducing exposure from animal reservoirs to minimize transmission.