Table 1

Clinical and genetic summary of congenital insensitivity to pain and erythromelalgia cases

CaseOnsetSexFamily historySCN9A mutationEMG†QST‡ for heat painLaser doppler tested§TST¶ or ARS†† anhidrosisNerve biopsy‡‡
#1InfancyMNo Nl>99%NoNlYes
#2InfancyMNo Nl>99%NoNlYes
#3InfancyFNo Nl>99%NoNlYes
#4InfancyMNo Nl>99%NoNlYes
#5InfancyFNo NlNoNoNlYes
#6InfancyMNo*R523>X, IVS8-2A>G, K655>RNlNoNoNoYes
#1TwentyFYes Nl<1%YesGlobalNo
#2TeensFYes Nl>99%YesNlNo
#3TeensFNo Nl<1%NoRegionalNo
#4SixtiesFNo NlNoNoNoNo
#5TeensFYes NlNoYesNlNo
#6TeensFNo NlNoYesRegionalYes
#8TeensFNo NlNlYesRegionalNo
#9SixtiesFYes Nl>99%YesNlNo
#10InfancyMYes NlNoYesRegionalNo
#11FortiesFYes NlNlYesRegionalNo
#12FiftiesFYes NlNoYesRegionalNo
#13TeensFYes Nl>99%YesRegionalNo
  • *Novel mutant variants. 

  • †EMG is electromyography and inclusive of sural and median sensory, peroneal, tibial and ulnar motor nerve conduction studies.

  • ‡QST is quantitative sensory testing that measures heat pain recognition where >95% represents insensitivity and <5% hyperalgesia compared with matched age and gender controls.19

  • §Erythromelalgia laser Doppler-tested patients who had findings consistent with erythromelalgia by having elevated skin temperature and blood flow at symptomatic distal extremities.2 ,3

  • ¶TST is thermoregulatory sweat test with regions of anhidrosis noted.38

  • ††ARS is autonomic reflex screen with abnormalities limited to sudomotor sweat function loss by quantitative sudomotor reflex testing with regions of anhidrosis noted.38

  • ‡‡All congenital insensitivity to pain patients had whole sural nerve biopsy studied with normal sensory fibre evaluation apart from CIP index case #6 who had skin biopsy nerve studied by PGP9.5 immunostaining.

  • CIP, congenital insensitivity to pain; Nl, tested and normal; QST, quantitative sensation testing.