RESUMO
Pain insensitivity disorders are rare; however, when individuals are insensitive to pain, they are significantly more vulnerable to physical injuries, with higher morbidity and mortality rates, compared with the general population. The authors present the case of an 11-month-old male infant with SCN 9A gene mutation that resulted in congenital insensitivity to pain, while his mother, with a different mutation of the same gene, had hypersensitivity to pain. This is a rare familial presentation of the extreme ends of pain sensitivity, and might be the first such example in medical literature. There is little available information regarding the treatment of pain insensitivity disorders. The authors provide a brief discussion regarding diagnosis (including differentials), known etiology, and treatment of congenital insensitivity to pain, of which a multidisciplinary treatment approach is recommended.