Congenital Syphilis

• Passes placenta after the third month of gestation

• Osteoblasts eventually contain spirochetes

• Skeletal lesions early in disease are

• Osteochondritis

• Osteomyelitis (diaphyseal)

• Periostitis

• These all occur early in the course of disease

• Osteochondritis

• Occurs at metaphysis

• Widens the zone of provisional calcification until there is epiphyseal separation (usually before age 3 moths)

• Dislocation is not pronounced

• X-ray shows lucent metaphyseal band

• Heals after 6 months of age

• Osteomyelitis

• In skull, may get geographic areas of destruction

• Periostitis

• Less common than osteomyelitis

• Course

• Even if lesions at this stage are not treated, they regress

• Remains latent for years and appears again around age 4 or later

• In later life, lesion is gummatous or non-gummatous osteomyelitis

• Usually affects skull, radius, tibia, ulna-especially skull and tibia

• Saber tibia results from growth stimulation of the tibia with forward bowing (in rickets the bowing is lateral and not forward)

• Also may get dactylitis, especially of proximal phalanx of index finger

• DDX: Birth trauma, rickets, severe malnutrition

• Other changes

• Nose-saddle nose

• Notched and narrowed incisors-Hutchinson’s teeth

• Periosteal reaction and new bone formation

• Especially proximal 2/3 of tibia shaft common late manifestation  

• Saber shin

• Bilateral forward bowing of tibia is conclusive evidence for acquired, tertiary syphilis although similar changes can occur with congenital form

• Acquired syphilis affects skull (mixed sclerosis and lysis)

• Clavicle and tibia