Spirochetes (not syphilis)

Question 1

Geo distribution of endemic spirochetes

• Yaws (T pallidum subsp pertenue)
• Bejel/endemic syphilis (T pallidum subsp endemicum)
• Pinta (T carateum)

Answer 1

• humid/tropical forests; Africa, Asia, Latin America, PAcific
• seminomadic tribes on isolated, dry areas of Sahel (southern border of Sahara), Arabian peninsula
• low-altitude areas/river basins of Central/South America, Caribbean

**In General: rural areas, or overcrowded conditions/poor hygeine. Rarely seen above/below 30th parallel

Question 2

Answer 2

Primary stage/lesion of Yaws

• raised, papular lesion at inoculation site - enlarges into nodules that ulcerate (resemble “raspberries” = “frambesia”)
• highly contagious
• pruritic –> autoinnoculation
• heals after several mos into hypopigmented area

Question 3

Answer 3

Secondary manifestations of Yaws

• secondary papules/scaly plaques
• plantar/palmar hyperkeratosis → “crab yaws” (children will have painful crab-like gait)
• conyloma lata in moist crevices
• periostitis/osteitis - long bones and phalanges (digital swelling)
• resolves w/in wks/mos (w/o scarring) even if untx

Question 4

Answer 4

Late/tertiary stage of Yaws

• occurs in 10% of untx pts - can be yrs later w/ asx latency stage
• Gangosa (rhinopharyngitis mutilans) = disfiguring chronic destruction of nasal/facial bone, cartilage, soft tissue
• Goundou = hypertrophic periostitis leading to exostosis of paranasal maxillae
• Saber shins = bowing of tibia d/t chronic periostitis
• Gummatous SQ nodules
• CNS/CV complications can occur

Question 5

Endemic Syphilis/Bejel = T pallidum subsp endemicum

Stages and most affected population

Answer 5

Primarily effects children (ages 2-15yo). Transmitted via direct contact/fomites

1. Primary - painless papula/ulcer in oropharynx (most don’t know, lasts for mos-yrs)
2. Secondary - after 3-6mos (resembles venereal syphilis). Heals w/in 6-9mos
   
   1. MM lesions, variable skin manifestations, laryngitis, cervical LAD
   2. long bone/hand osteitis/periostitis (similar to Yaws)
3. Tertiary - common (25-50%) by teenage yrs/early adult
   
   1. Gummatous lesions in skin/mucosal areas
   2. Gangosa (similar to yaws)
   3. Saber shins
   4. Neuro/CV involvement

Question 6

Answer 6

Lepto - very fine coils, hooked ends (question mark hooks)

Question 8

conjunctival suffusion and muscle tenderness (calf, lumbar spine)

Answer 8

characteristic signs of acute, septicemic stage of lepto

lasts 5-7 days

Question 9

Immune phase of lepto

Answer 9

(in addition to acute phase symptoms)

• jaundice (d/t liver failure)
• renal failure - nonoliguric, hypoK, impaired Na resorption
• aseptic meningitis (intense fronto-temporal HA) - lymphocytic pleocytosis
• pulmonary hemorrhage, ARDS
• rare: encephalitis, TM, GBS

Question 10

Tx of lepto

Answer 10

• mild (PO)
  
  • doxy x7 days or azithro x3 days
• severe
  
  • IV PCN
  • CRO
  • Doxy

Question 11

2 types of relapsing fever

Answer 11

1. Epidemic TBRF
   
   1. >20 spp of Borrelia spp
   2. Argasidea tick
2. Endemic LBRF
   
   1. B recurrentis
   2. Pediculus humanus (body louse)

Question 12

RF for LBFR

Answer 12

(d/t B recurrentis from body louse)

• endemic in Horn of Africa
• commonest in rainy seasons
• overcrowding (homeless, crowded shelters), refugee camps, poor hygiene, famine, waters
  
  • epidemics during WWI and WWII

Question 13

Answer 13

Borrelial lymphocytoma

• solitary red-blue lesion, painless
• often on ear, nipple, scrotum
• histo = polyclonal B cell infiltrate
• Mostly w/ B afzelii (Eurasian)