Campylobacter Species Overview and Pathogenesis

Campylobacter Species Overview

• Gram-negative, oxidase-positive, motile rods with complex growth requirements
• Campylobacter jejuni is a subtype, appearing as a seagull-shaped rod with a single flagellum
• Isolation often uses Campy plates, a selective medium for stool samples

Campylobacter jejuni Pathogenesis

• Ingestion leads to invasion and damage of the jejunum, ileum, and colon mucosa
• Endotoxins, enterotoxins, and cytotoxins are produced, though their precise role isn't fully understood
• Gastric acid and the immune system (complement) initially inhibit the bacteria
• C. jejuni can penetrate host cells and pass the epithelial layer
• Mesenteric lymph nodes can become inflamed and enlarged in severe infections

Campylobacter jejuni Symptoms

• Common symptoms include watery, bloody diarrhea, malaise, fever, abdominal pain, and cramps
• Illness is usually self-limiting, lasting at least a week
• Symptoms peak in young adults

Epidemiology of C. jejuni Infection

• Risk factors of infection include lack of stomach acid and hypogammaglobulinemia
• Infection severity and incidence are higher in young adults

Clinical Findings and Diagnosis

• Average incubation period is 3-7 days
• Prominent symptoms are abdominal pain and diarrhea, with nausea being common and vomiting less so
• Severe, watery diarrhea is common
• White blood cells (leukocytes) are often found in feces
• Symptoms typically resolve within a few days
• C. jejuni infection is clinically similar to Salmonella or Shigella infections, but abdominal pain tends to be more severe with C. jejuni
• In less developed areas, infection may manifest as milder diarrhea, and asymptomatic colonization is more frequent

Laboratory Diagnosis of C. jejuni

• Refrigerate stool samples immediately for transport to the lab
• Use specialized transport media for rectal swabs
• C. jejuni can be identified directly in liquid stool samples via microscopy (assessing motility and morphology)
• Isolation relies on selective media to suppress other bacteria in the stool sample
• Culture is more often performed than direct microscopy

Treatment of C. jejuni Infection

• Rehydration is crucial
• Erythromycin or quinolones may be used for treatment

Prevention and Control of C. jejuni

• Safe food handling practices to prevent contamination (especially poultry, milk, and water) are key

This quiz covers essential information about Campylobacter species, focusing on Campylobacter jejuni. It explores its characteristics, pathogenesis, symptoms, and epidemiology. Test your knowledge on this significant pathogen and its impact on human health.