Campylobacteriosis

Overview

Campylobacteriosis is an acute bacterial infection most often caused by Campylobacter jejuni. It primarily affects the intestine and is one of the common bacterial causes of diarrheal illness. Infection can occur after ingesting a small amount of contamination, so cross-contamination from raw poultry to ready-to-eat food can be enough to cause disease. ^{[1] [2]}

The bacteria invade and inflame the intestinal mucosa, producing abdominal pain and inflammatory diarrhea that may contain blood. Systemic infection is uncommon but can occur, especially in people with weakened immunity. Immune responses triggered by the infection can occasionally lead to post-infectious complications even after the diarrhea has resolved. ^{[1] [2]}

Campylobacter infection often resembles other bacterial gastroenteritis. A travel history, animal contact or poultry exposure can be useful, but no single exposure pattern is diagnostic. Clinical care focuses first on hydration and severity. Stool testing is particularly useful when illness is severe, persistent, bloody, occurs in a high-risk patient or has public-health implications. ^{[1] [2] [3]}

Symptoms and warning signs

Symptoms generally begin two to five days after exposure. Diarrhea, often bloody, is accompanied by abdominal cramps or pain, fever and nausea; vomiting can occur. Some patients develop severe abdominal pain that mimics appendicitis or inflammatory bowel disease. Most otherwise healthy people improve over several days. ^{[1] [2]}

Urgent assessment is appropriate for severe dehydration, inability to keep fluids down, fainting, very low urine output, high or persistent fever, severe abdominal pain, significant bloody diarrhea or signs of sepsis. Infants, older adults, pregnant people and those with weakened immune systems have a lower threshold for medical evaluation. ^{[1] [2]}

Diagnosis

Campylobacter can be identified from stool with culture-independent diagnostic testing such as PCR or antigen testing, or by culture. Molecular panels provide rapid detection but do not always yield antimicrobial susceptibility data. When resistance information or public-health typing is needed, culture confirmation of a positive molecular result can be useful. ^{[1] [2]}

Additional tests depend on severity. Electrolytes and kidney function may be checked in dehydrated patients. Blood cultures can be appropriate in severe systemic illness or marked immune compromise. A positive test must be interpreted in context because multiplex panels can identify more than one pathogen and management should match the clinical syndrome. ^{[1] [2] [3]}

Salmonella, Shigella, STEC, Yersinia, viral gastroenteritis, Clostridioides difficile and inflammatory bowel disease can produce similar symptoms. Severe right-lower-quadrant pain may resemble appendicitis. The presence of bloody diarrhea also affects decisions about empiric antibiotics because some enteric pathogens require different management. ^{[2] [3]}

Causes, risk factors and clinical context

Risk factors include eating undercooked poultry, cross-contamination during food preparation, drinking unpasteurized milk or untreated water, and contact with infected animals, including puppies. Person-to-person spread is less common. Older adults, pregnant people and immunocompromised patients are more likely to experience severe disease. ^{[1] [2]}

CDC notes that most people recover completely within about one week. Diarrhea can resolve before fatigue or appetite normalize. Antibiotics are not needed for most uncomplicated infections. Persistent symptoms should prompt reassessment for dehydration, another pathogen, inflammatory bowel disease or a complication. ^{[1] [2] [3]}

Complications and why the diagnosis matters

Post-infectious reactive arthritis and irritable bowel syndrome can occur. Campylobacter is also a recognized trigger of Guillain–Barré syndrome, an uncommon neurologic disorder causing progressive weakness. Bacteremia and other invasive complications are uncommon but matter in people with severe immune compromise. ^{[1] [2]}

The prognosis is excellent for most otherwise healthy people. CDC estimates that a small fraction of Campylobacter illnesses precede Guillain–Barré syndrome, although Campylobacter accounts for a substantial share of GBS cases overall. Severe dehydration and invasive infection are the main short-term threats. ^{[1] [2] [3]}

Treatment and management

Oral rehydration and continued fluid intake are the foundation of treatment. Most infections do not require antibiotics. Antibiotic therapy is considered for severe illness and for people at increased risk of severe disease. Azithromycin is commonly used; fluoroquinolones may be active but resistance is common, so susceptibility data and local guidance matter. ^{[1] [2]}

Use oral rehydration solution when fluid losses are substantial and seek intravenous fluids if oral intake cannot keep pace. Antidiarrheal medicines are not appropriate for every patient, particularly with high fever or bloody diarrhea, and should be discussed with a clinician. Nutrition can resume as tolerated. ^{[1] [2] [3]}

Do not take leftover antibiotics simply because diarrhea is bloody. Unnecessary antibiotics expose patients to side effects and may be inappropriate for another enteric pathogen. When antibiotics are indicated, selection should account for resistance and patient factors rather than relying on a one-size-fits-all regimen. ^{[1] [2]}

Follow-up, recovery and prevention

Most patients need no routine test of cure once symptoms resolve. Follow-up is warranted for prolonged diarrhea, recurrent fever, persistent weight loss, joint symptoms or new neurologic weakness. Progressive tingling or weakness after a diarrheal illness needs urgent assessment for possible Guillain–Barré syndrome. ^{[1] [2]}

Cook poultry thoroughly, prevent raw-poultry juices from contaminating other foods, wash hands after handling raw meat or animals, choose pasteurized dairy products and use safe drinking water. People with diarrhea should practice careful hand hygiene and avoid preparing food for others when advised by public-health guidance. ^{[1] [2] [3]}

Special situations and care pathway

Pregnancy, older age and immune suppression increase concern for severe disease. In outbreak settings, stool culture and isolate submission may be important for epidemiologic investigation. Travelers should pay attention to food and water safety, but many infections are acquired domestically. ^{[1] [2] [3]}

Assess hydration and red flags, obtain stool testing when severity or public-health context warrants it, treat fluid losses, reserve antibiotics for severe or high-risk disease, and review for post-infectious complications when symptoms persist. Culture can supplement molecular testing when susceptibility or strain data are needed. ^{[1] [2]}

When to seek urgent medical care

Seek urgent care for severe dehydration, fainting, reduced urination, persistent high fever, severe abdominal pain, large-volume bloody diarrhea, signs of sepsis or new progressive weakness after the gastrointestinal illness. ^{[1] [2]}

Sources

1. CDC — Clinical Overview of Campylobacter
2. CDC — Treatment of Campylobacter Infection
3. WHO — Campylobacter — fact sheet

This article is based on trusted medical sources and is awaiting clinician review. It is not a substitute for personalized medical advice.