We describe the case of a patient presenting with bilateral mydriasis and first diagnosis of Hodgkin’s lymphoma.
Pathophysiologically, we consider the enlarged lymph nodes as irritating the pericarotid sympathetic nerves, causing oculosympathetic spasm and ultimately resulting in autonomic dysfunction clinically manifested by pupillary dilation.
The pupillary dilator muscle is innervated by the sympathetic nervous system . The first neuron of this pathway is located in the hypothalamus. Exiting axons descend uncrossed through the brainstem tegmentum into the spinal cord to the level of C8–T1, where the second-order fibers begin and ascend in the sympathetic chain over the pulmonary apex to the superior cervical ganglion.
Postganglionic sympathetic fibres ascend from the superior cervical ganglion, along the walls of the internal carotid artery and innervate the ciliary ganglion activating the pupillary dilator muscle.
Pathologies of the brain stem as a potential differential diagnosis were clinically unlikely since all other brain stem reflexes, like the corneal reflex, remained intact and were eventually excluded by two unremarkable MRI scans of the brain.
We assume the detection of HSV-DNA in the CSF with low genome concentration to be a reactivation, possibly due to altered immune system in Hodgkin’s lymphoma disease, and in no causal link to the mydriasis.
The mild improvement of the mydriasis after the start of chemotherapy supports our hypothesis. However, as in most observational case studies a causality cannot be proved with absolute certainty.
Neurologic complications from Hodgkin’s lymphoma are overall rare. Direct neurologic dysfunction can be caused by metastases of the central nervous system and depending on the site of metastasis result in cranial nerve palsies, headaches and gait disturbance. Indirect affection of the central or peripheral nervous system by paraneoplastic syndromes can cause cerebellar degeneration and clinically present with dysarthria, nystagmus and ataxia .
The case presented herein shows a bilateral mydriasis as the primary clinical manifestation of Hodgkin’s lymphoma.
To the best of our knowledge, this is the first reported case of mydriasis in association with Hodgkin’s lymphoma. Other reports described Horner syndrome in a patient with Hodgkin’s lymphoma with enlarged mediastinal lymph nodes  and oculosympathetic spasm with unilateral, intermittent mydriasis in a case of dissection of the internal carotid artery .
In conclusion, this case emphasizes the importance of detailed diagnostic, especially imaging of structures around the sympathetic pathway, in cases of autonomic dysfunction such as mydriasis.