Spirochetes

• What is the order of spirochetes?

  Spirochaetales
• Which families are included in spirochetes classification?

  Leptospiraceae and Spirochaetaceae
• Name three genera of spirochetes.

  Leptospira, Borrelia, and Treponema
• What diseases are caused by spirochetes?

  Syphilis, zoonoses, Lyme disease, relapsing fever
• Describe the morphology of spirochetes.

  Obligate aerobic helical rods, tightly coiled
• How do spirochetes move?

  Rapid translational and rotational motion
• What is a characteristic feature of Leptospira under electron microscopy?

  Long axial filament covered by a fine sheath
• Why can't Leptospira be readily stained?

  They require silver impregnation for visualization
• What is the incubation period for leptospirosis?

  3 to 30 days, usually 10 to 12 days
• What are the initial symptoms of leptospirosis?

  Fever, chills, headache, malaise, myalgia
• How do Leptospira enter humans?

  Through small breaks in skin or intact mucosa
• What virulence factors do Leptospira possess?

  Reduced phagocytosis, hemolysin, endotoxins
• What severe condition can result from Leptospira infection?

  Weil's disease, causing jaundice and renal failure
• What specimens are collected for leptospirosis diagnosis?

  Blood, cerebrospinal fluid, and urine
• When is the optimal time to collect urine for leptospirosis diagnosis?

  Higher yield after the first week
• What is the recommended protocol for specimen inoculation?

  Direct inoculation into specific laboratory media
• How should urine samples be treated before examination?

  Diluted to minimize inhibitory substances
• What is the morphology of Borrelia organisms?

  Flexible, varying in thickness, spirals of 3 to 10
• What distinguishes Borrelia from other spirochetes?

  Different pathogenic properties and host ranges
• What is the incubation period for B. recurrentis infection?

  2 to 15 days
• What characterizes relapsing fever caused by Borrelia?

  Acute febrile episodes that recur
• What are the two varieties of relapsing fever?

  Tickborne and louseborne
• What is the classic skin lesion of Lyme disease?

  Erythema migrans, a red macule
• How does B. burgdorferi facilitate tissue invasion?

  By binding plasminogen and acting as a protease
• What is the two-tiered approach for Lyme disease diagnosis?

  Screening test followed by confirmation test
• What is the primary prevention measure for Lyme disease?

  Control exposure to arthropod vectors
• What are the clinically significant species of Treponema?

  1. pallidum subsp. pallidum, pertenue, endemicum, carateum
• How are Treponema organisms visualized?

  Difficult to visualize with bright field microscopy
• What is the movement characteristic of Treponema?

  Graceful flexuous movements in liquid
• What are the key characteristics of spirochetes?

  • Obligate aerobic helical rods
  • Tightly coiled, thin, and flexible
  • Rapid translational and rotational motion
• What are the clinical manifestations of leptospirosis?

  • Initial phase: fever, chills, headache, malaise, myalgia
  • Subsequent phase: hepatic, renal, and CNS involvement
• What is the recommended specimen collection protocol for leptospirosis?

  • Collect blood or CSF in the first week
  • Collect urine after the first week
  • Direct inoculation into laboratory media
• What are the stages of Lyme borreliosis?

  • Stage 1: Erythema migrans
  • Stage 2: Early disseminated symptoms
  • Stage 3: Late persistent infections
• What are the methods for diagnosing Lyme disease?

  • Two-tiered approach: screening and confirmation tests
  • Serologic tests for IgM and IgG
  • PCR testing for leptospire DNA
• What are the morphological characteristics of Treponema?

  • Thin, spiral organisms
  • Regular and angular spirals
  • Three periplasmic flagella at each end
• What is the causative agent of Lyme disease?

  1. burgdorferi sensu lato
• How are organisms of B. burgdorferi sensu lato transmitted?

  Via bite of infected Ixodes ticks
• Which species of B. burgdorferi sensu lato cause Lyme disease?

  At least three species
• Where does B. burgdorferi stricto occur?

  North America & Europe
• Where do B. garinii and B. afzelii occur?

  Asia and Europe