Campylobacter Species Overview and Pathogenesis

Study Notes

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

Description

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.