Introduction: Type I neurofibromatosis is an autosomal dominant disorder with an estimated prevalence of 1/3,000. Half of the new cases are due to mutations; their penetration is complete in adults and may affect any ethnic group. We describe the first reported case of type I neurofibromatosis in a Kaxinawa Indian from the state of Acre, Brazil, in whom the presenting symptoms were of progressive tetraparesis due to multiple paraspinal neurofibromata.
Clinical case: A 16 year old indigenous Kaxinawa boy presented with progressive myelopathy for the past six months. On neurological examination he had hyperreflexive spastic tetraparesia, predominantly on the right side, with the sensory level at C3/C4, multiple medullary automatisms and respiratory difficulty. He also had diffuse café-au-lait stains, including one particularly prominent one measuring 15 cm on his right buttock. MR of the spine showed many hypo-intense lesions at T1 and hyperintense lesions at T2, which took up contrast and were present at all the conjugation foramens bilaterally. These lesions originated at the roots and were suggestive of neurofibromata. On mediastinal tomography there were several neurofibromata in the mediastinum. The patient had a surgical operation for spinal decompression, with a laminectomy at C1/C2 and removal of the neurofibromata on the spinal cord at C1 and C2. The patient has a sister with multiple café-au-lait stains.
Conclusions: Because of the traditional isolation of the Kaxinawa Indians, with whom contact was made at the beginning of the twentieth century, this first case reported of type I neurofibromatosis may be due to a new mutation which presented as a florid form of the disease with multiple spinal neurofibromata.