SPIROCHETES

• What are spirochetes classified as?

  Gram-negative bacteria
• What is the order that spirochetes belong to?

  Spirochaetales
• What are the key structural features of spirochetes?

  • Helically coiled shape
  • Axial fibrils (endoflagella) for motility
• Which genera of spirochetes are of clinical importance?

  Treponema, Borrelia, Leptospira
• What are the general characteristics of Treponema?

  • Slender spirochetes with tight coils
  • Microaerophilic
  • Best observed using dark-field microscopy
  • Poorly stainable with Gram or Giemsa stains
• What is the pathogenic species of Treponema that causes venereal syphilis?

  Treponema pallidum subsp. pallidum
• How is Treponema pallidum subsp. pertenue characterized?

  It causes Yaws
• What is the transmission method for Treponema pallidum?

  Sexual contact, transplacental, non-venereal
• What are the stages of venereal syphilis caused by Treponema pallidum subsp. pallidum?

  1. Primary: Painless chancre
  2. Secondary: Rash, flu-like symptoms
  3. Latent: Asymptomatic with reactive serology
  4. Tertiary: Gummas, neurosyphilis, cardiovascular issues
  5. Congenital: Hutchinson’s triad and bone deformities
• What are the symptoms of congenital syphilis?

  Hutchinson’s triad and bone deformities
• What are the laboratory diagnosis methods for Treponema infections?

  • Specimen collection from primary lesions
  • Dark-field microscopy
  • Fluorescent antibody test (DFA-TP)
  • Nontreponemal tests (VDRL, RPR)
  • Treponemal tests (FTA-ABS, TPHA, MHA-TP)
  • Molecular methods (PCR)
• What is the optimal method for detecting Treponema pallidum in primary lesions?

  Dark-field microscopy
• What does the VDRL test measure?

  Reagin antibodies against cardiolipin
• What is a limitation of the RPR test?

  False-negative results in early infections
• What are the characteristics of Borrelia spirochetes?

  • Thicker spirochetes with 3–10 loose coils
  • Actively motile with endoflagella
  • Stain well with Giemsa and Wright stains
  • Microaerophilic or anaerobic
• What is the primary pathogenic species of Borrelia that causes relapsing fever?

  Borrelia recurrentis
• What are the stages of Lyme disease?

  1. Stage 1: Erythema migrans, flu-like symptoms
  2. Stage 2: Neurological and cardiac symptoms
  3. Stage 3: Chronic arthritis and skin rash
• What is the most common method for detecting Borrelia during febrile episodes?

  Dark-field microscopy
• How is Lyme disease transmitted?

  Via Ixodes ticks
• What is the primary screening test for Lyme disease antibodies?

  Enzyme-Linked Immunosorbent Assay (ELISA)
• What are the general characteristics of Leptospira?

  • Spiral-shaped spirochetes
  • Right-handed helices with hooked ends
  • Free-living and parasitic
  • Classified into saprophytic and pathogenic strains
• What is the primary pathogenic strain of Leptospira responsible for most human cases?

  Leptospira interrogans
• How is leptospirosis transmitted?

  Contact with infected animal urine or tissues
• How do pathogenic leptospires enter the body?

  Through breaks in skin or mucous membranes
• What are the key features of leptospirosis pathogenesis?

  • Zoonotic disease
  • Rapid invasion of the bloodstream
  • Symptoms include fever, chills, and muscle aches
• What is PCR widely used for in Lyme disease diagnosis?

  Diagnosis of erythema migrans and neuroborreliosis
• Why can PCR results for Borrelia in CSF be variable?

  Results depend on the stage of disease
• What shape are Leptospira organisms?

  Spiral-shaped spirochetes
• What are the two types of Leptospira strains?

  Saprophytic and pathogenic strains
• Which strain of Leptospira is responsible for most human leptospirosis cases?

  Leptospira interrogans
• How are Leptospires classified?

  Based on molecular techniques like 16S rRNA sequencing
• How is leptospirosis transmitted?

  Through contact with infected animal urine or tissues
• How do pathogenic leptospires enter the body?

  Through breaks in the skin or mucous membranes
• What organs do pathogenic leptospires spread to after entering the bloodstream?

  Liver, kidneys, and central nervous system
• What characterizes anicteric leptospirosis?

  High fever and severe headache
• What is Weil’s Disease?

  Severe disease involving liver failure and kidney dysfunction
• What is the mortality rate for Weil’s Disease?

  Can reach 10%
• What specimens are collected during the acute phase of leptospirosis diagnosis?

  Blood, CSF, and peritoneal dialysate
• When is urine collected for leptospirosis diagnosis?

  From the second week to 30 days after onset
• What microscopy method is used to visualize motile Leptospira?

  Dark-field microscopy