STD

Question 1

Which organism gives rise to Syphilis

Answer 1

T. pallidum

a spirochaete

Question 2

Characteristics of T. pallidum

Answer 2

• Spiral bacteria
• 5-15 um in length
• Limited reproductive ability in vitro
  
  • Obligate human parasite
• Transmission: sexually, vertical, blood

Question 3

Classification of T. pallidum infections

Answer 3

• Acquired:
  
  • Early
    
    • Primary: microscopy, not painful, highly infectious, males — 9-90 days incubation
    • Secondary: Multisystem, skin lesions, meningititsm palsy, within 8 weeks of infection,
  • Late
    
    • ​Late: >2 years of infection
    • Neurosyphilis, Cardiovscular syph, gummatus syph(skin lesions)
• Congenital

Question 4

Diagnosing T. pallidum

Answer 4

Primary lesion: Dark field microscopy

Other: Serology

• Treponemal specific screening test
• Non-treponemal specific test

Both need to be possitive

Question 5

Treatmen for T. pallidum

Answer 5

Procaine penicillin

Question 6

A gram negative diplococchi

Answer 6

N. gonnorhoea

Question 7

Which tissues are affected by direct ghonoreal infection

Answer 7

Mucosal tissues

Urethra, cervic, opthalmic disease in newborwns

Question 8

Sites of local extension in gonnorhea

Answer 8

• Prostatis, vesiculitis, epididymtis, infertility

Endometritis, pelvic perotinits, infertility

Question 9

Some special characteristics of ghonnorea

Answer 9

• Pus filled lesions e.g. foot
• Amplifies HIV infection
• Infected cells capable of bacterial DNA uptake, can switch on/off proteins

Question 10

Diagnosis of gonnorhea

Answer 10

• Nucleis acid amplification test on urine
• Characteristic diplococci

Question 11

Treatment of ghonnorea

Answer 11

• Some are untreatable, resistance major problem
  
  • Resistance to peincillin, tetracycline, fluoroquines
• Give third gen cehpalosporins
  
  • Ceftriaxone
  • or Ciprofloxacin

Question 12

How does chlamydia exist in eukaryotes

Answer 12

• As in intracellular parasites, exists as an inert elementary body EB
  
  • Attachment: EB interacts with cell surface
  • Ingestion: Phagocyte phagocytoses
  • Phagosome fusion: Chlamydia able to survive this
  • Reorganisation: EB transforms to RB
  • Multiplication: RB multiplies in phagosome
  • Condensation: RB->EB
  • Mature inclusion: Increase in number
  • Extrusion and release: Infectious EB released and process continues

Question 13

Clinical features of Chlamydia

Answer 13

• Trachoma
• Inclusion conjuctivitis
• Lymphogranuloma venerum
• Urethritis
• Epididymitis
• Proctitis