Holocord syrinx presenting as hemi anhidrosis.

We present a 41-year-old man with Chiari type 1 malformation and syrinx up to tenth thoracic level who presented with left side hemi anhidrosis. Neurological findings of syrinx were absent in this case. Though Horner's syndrome is reported, this report is probably first.

INTRODUCTION

Horner's syndrome, along with weakness and atrophy of upper limb, as well as anaesthesia to pain and temperature, is well recognized finding in patients with syringomyelia. Few cases have been reported regarding isolated Horner's syndrome as a presenting manifestation of a Chiari I malformation with syringomyelia.[1] We report a 41 year old man with left side hemi hidrosis probably a part of Horner's syndrome who was found to have a Chiari I malformation with holocord syrinx.

CASE REPORT

A 41-year-old man presented in medicine ward with a complaint of neck and back pain and loss of sweating in right side of the body that had begun eight months before. There was no history of trauma that could account for the pain. There was no history of dizziness or difficulty in swallowing. There was no history of hypertension, diabetes, and immunocompromised status. On examination whole left side of body including face was dry, there was no evidence of sweating [Figures 1 and 2]. Anhidrosis was tested by spoon test. This test is described as drawing a metal spoon across the surface of the skin after adequate physical Exercise. We could not do iodine starch test due to inadequate facility. There was slight ptosis on left side with normal pupil size bilaterally. Neurological examination was unremarkable with no limb weakness, wasting or numbness and temperature impairment on the side of anhidrosis. There was no facial asymmetry. His routine laboratory tests were within normal parameters. His chest x-ray was normal. This was done to rule out any mass in the upper lobe of the lung which may present as Horner syndrome. MRI spine was performed which showed hyperintense signal (red arrow head) in T2-weighted sections extending whole spinal cord up to eighth thoracic cord level with herniation of cerebellar tonsil (blue arrow head) compatible with syringomyelia along with Chiari I malformation [Figure 3]. Surgical treatment was recommended but the patient refused.

Figure 1

Dry left nipple with anhyrosis

Figure 2

Dry left hand

Figure 3

Holocord syrinx up to 8th spinal cord level (red arrow head), herniation of cerebellar tonsil (blue arrow head)

DISCUSSION

Syringomyelia is the development of a fluid-filled cavity or syrinx within the spinal cord. More than half of all cases are associated with Chiari type 1 malformations in which the cerebellar tonsils protrude through the foramen magnum and into the cervical spinal canal.[2] The pathogenesis of syringomyelia is not fully understood. It may occur after a trauma, secondary to a tumor, craniocervical or intracerebral pathology or idiopathic.[3] The eccrine sweat glands are innervated by the sympathetic nervous system. Fibers originating in the cerebral cortex traverse the hypothalamus, and then cross in the medulla to the lateral horn of the spinal cord. These fibers leave the spinal cord to synapse in the sympathetic ganglia with neurons that innervate the sweat glands.[4] Thus, a cortical lesion will cause contralateral anhidrosis, a lesion in the medulla could result in contralateral or ipsilateral anhidrosis, and any lesion distal to the medulla will cause ipsilateral anhidrosis. Slowly progressive tissue damage around the syrinx reaches the lateral horn, it will segmentally affect the sympathetic preganglionic neurons or adjacent structures.[5] We performed a “PubMed”, and “Google Scholar” search for publications dealing with anhidrosis in syringomyelia there was lack of information regarding this. In our case probable hypothesis may be hypo activity due to autonomic disturbances because of progressive and irreversible damage to the sympathetic preganglionic neurons due to expanding syrinx. However more hypotheses should be explored for its mechanism. Physicians should be aware of the different ways in which syringomyelia can present to ensure its early diagnosis.

Anhidrosis of the face and upper part of the body, segmental anhidrosis is reported in Horner syndrome and syringomyelia but hemi hidrosis of the whole boy was unique in this case.