Pathogens: Campylobacter and Bordetella

Campylobacter-Reed

• Campylobacter enteritis is typically caused by C. jejuni or C. coli.
• Causes fever, severe abdominal pain, and diarrhea (watery or bloody stools).
• Fever usually resolves within 2 days, but diarrhea and abdominal pain can last 4-6 days.
• Diagnosis involves stool or blood cultures, showing gram-negative, curved rods
• Commonly found in the gastrointestinal tract of many animals, including household pets (cats, dogs, and birds).
• Can be present in virtually all parts of the body, especially in immunocompromised individuals.
• The disease is self-limiting and treatment can be shortened by 1 day with antibiotics like azithromycin (single 1g dose or 500mg daily for 3 days).
• Potential sequelae include Guillain-Barré syndrome, multiple sclerosis, grave's disease, and other potentially fatal conditions like primary bacteremia, endocarditis.

Bordetella Pertussis

• The organism's most important virulence factor is pertussis toxin.
• Toxin ADP-ribosylates a guanine nucleotide, affects the circulation of lymphocytes, and serves as an adhesin
• Risk: High risk in children under 2 years of age
• Has 3 phases: catarrhal, paroxysmal, and convalescent, which have specific symptoms/timeframes.
• Diagnosis: Clinical presentation and nasopharyngeal secretion culture or PCR.
• Treatment options: supportive care as needed and macrolide (azithromycin PO × 5 days)
• Other Treatment: if contraindicated, TMP-SMX can be used.
• Potential sequelae: pneumonia, and failure to thrive, in severe cases.

Chlamydia Trachomatis

• STD that causes lesions of the genitalia.
• Four main serotypes cause infections, two with significant systemic manifestation and two that cause eye infections (conjunctivitis).
• Diagnosed with urine culture or cervical swab and NAAT test of the sample.
• Treatment options: azithromycin or doxycycline
• Complications include Pelvic inflammatory disease (PID) and ectopic pregnancy in some cases.
• Other complications: epididymitis, and potentially urethritis

Haemophilus Influenzae

• Gram-negative coccobacillus that enter the respiratory tract.
• Facultative anaerobe.
• Encapsulated, which allows resistance to phagocytosis.
• Mostly affects the nose, throat, and respiratory system.
• Treatment: Antibiotics (Bactrim if a beta-lactamase is produced, first-generation cephalosporins for skin infections, and ampicillin/Rocephin IV for epiglottitis)
• Potential sequelae: Epiglottitis, and breathing failure are particularly serious.
• Other conditions include aegyptus which causes conjunctivitis, and ducreyi that causes painful genital chancre.

Moraxella Catarrhalis

• Gram-negative, aerobic diplococcus.
• Very similar to Neisseria.
• Primarily colonizes the respiratory tract in healthy adults
• Symptoms: sinusitis, otitis media, bronchitis, and pneumonia
• Treatment: Beta-lactamase antibiotics, such as Augmentin or Unasyn (amoxicillin-clavulanate potassium).
• Potential sequelae: mastoiditis

Neisseria Gonorrhoeae

• Colonizes the mucosal surfaces of the genital tract.
• Diagnosis:
• Male: urine test
• Female: cervical swab.
• Symptoms: milky white discharge, burning during urination
• Treatment: First-line treatment: ceftriaxone IM injection (500mg).
• Other potential sequelae: Meningitis and other complications (e.g severe, immunocompromised)

Neisseria Meningitidis

• Found in the nasopharyngeal region (3-25% of individuals are colonized).
• Transmitted through epithelium to the submucosa and then the bloodstream.
• Commonly causes infections of the meninges resulting in meningitis.
• Symptoms: fever, headache, stiff neck; disseminated intravascular coagulation may result in skin rash (purpura) in more severe cases.
• Treatment: IV ceftriaxone 2g every 12 hours.

Salmonella

• One of the most common causes of diarrhea.
• Symptoms develop 12–36 hours after infection.
• Gram negative, motile rod, peritrichous flagella, non-spore forming, and facultative aerobe
• Common symptoms: diarrhea, fever, and abdominal cramps.
• Treatment: ciprofloxacin for severe illness.

Borrelia Burgdorferi

• Transmitted via ixodides (deer tick bite).
• Early localized infection (EM) is characterized by erythema migrans, which is a characteristic skin rash (7-10 days after).
• Early disseminated (days to weeks later) involves the joint, cardiac (pericarditis, arrhythmia, heart block), and musculoskeletal symptoms.
• Late persistent infection includes arthritis, chronic neurological problems (e.g., encephalopathy), and other systems.
• Diagnosis: Primarily based on clinical presentation and lab investigation (e.g., ELISA)

Staphylococcus Aureus

• Common skin and soft tissue infections: impetigo, abscesses, TSST-1, pneumonia, osteomyelitis
• Risk factors: Immunocompromised patients, broken skin, or cuts
• Diagnosis: Wound or blood cultures
• Treatment: Antibiotics 4-6 weeks of IV antibiotics, and removal of medical implants in severe cases.
• Potential complications: osteomyelitis, bacteremia, endocarditis, and toxic shock syndrome.

Streptococcus

• Gram positive, arrangement- in pairs or chains
• Mostly facultative anaerobes.
• Common infections- pharyngitis (strep throat), impetigo, cellulitis.
• The most serious potential complication of strep throat is acute rheumatic fever and rheumatic heart disease.
• Other conditions: puerperal fever, bacterial endocarditis, and pneumonia.

Bacillus Anthracis

• Three types (cutaneous, pulmonary, GI tract)
• Cutaneous: Spores enter through skin breaks causing an ulcer with black eschar.
• Pulmonary (Inhalation): spores inhaled leading to lung and mediastinal infections
• Diagnosis: clinical presentation (e.g. ulcers, lymph node swelling, chest pain) and laboratory tests
• Treatment: antibiotics needed immediately (e.g., ciprofloxacin, doxycycline).

Escherichia Coli

• Many forms with varying symptoms and treatments
• EIEC: causes bloody diarrhea.
• ETEC: most common cause of traveler's diarrhea. Bloody diarrhea
• EPEC: causes watery diarrhea in infants/young children.
• EHEC or STEC: associated with diarrhea (possibly bloody) and can cause hemolytic uremic syndrome.

Shigella

• Caused by infection with Shigella species.
• Disease: transmitted by ingestion of Shigella via contaminated hands, food, and water
• Can cause dysentery (bloody diarrhea) in severe cases, often in children
• Treatment: Primarily supportive care (hydration, rest). Ciprofloxacin or azithromycin for severe conditions, Anti-motility drugs avoided

Mycobacterium

• Leading cause of death from infectious agent worldwide
• Two main forms: TB, MAC
• Transmission: inhalation of aerosolized droplets
• Treatment: multi-drug regimen for months; for TB, four drugs (RIPE); MAC typically involves different antibiotics

Explore the characteristics and effects of Campylobacter and Bordetella pertussis in this quiz. Learn about the symptoms, diagnosis, and potential complications associated with these pathogens. Test your knowledge on their virulence factors and treatments available for infections.