Conjunctival biopsy to diagnose neurosarcoidosis in patients with inflammatory nervous system disease of unknown etiology

Neurosarcoidosis in an adult man with a family history of MS: A case report

Key clinical message

According to this report, a biopsy revealed a diagnosis of neurosarcoidosis in a patient with a history of MS. The development of the disease can be slowed down by early diagnosis and appropriate treatment.

Abstract

Neurosarcoidosis is a rare type of sarcoidosis that affects the central nervous system (CNS). Herein, we present a case of neurosarcoidosis with a history of multiple sclerosis (MS). Based on the pathological findings of the biopsy, a diagnosis of neurosarcoidosis was established. The administration of appropriate treatment at an early stage can assist in decelerating its progression.

Neuro-Ophthalmic Manifestations of Sarcoidosis

BACKGROUND

Sarcoidosis is an idiopathic, multisystem, inflammatory disease that has central nervous system involvement in 5%-15% of cases. The presentation of neurosarcoidosis is highly variable, and the MRI findings often mimic the appearance of other central nervous system diseases. Therefore, the diagnosis can be challenging. About one-third of neurosarcoidosis cases have neuro-ophthalmic manifestations and, thus, may be evaluated by a neuro-ophthalmologist early in the disease course.

METHODS

We performed a retrospective review of 22 cases of biopsy-proven sarcoidosis with neuro-ophthalmic manifestations, seen at the Wilmer Eye Institute from January 2013 to September 2019, in which we described the demographic information, clinical presentations, neuroimaging findings, and diagnostic evaluations.

RESULTS

Twenty-two patients were included. Fifteen patients identified as black and 7 as white. Fifteen were women, and 7 men. Mean age at sarcoidosis diagnosis was 45.9 years (range 26-66). Neuro-ophthalmic findings included optic neuropathy in 11 (50%); proptosis/orbital inflammation in 5 (23%); abducens palsy in 5 (23%); trochlear palsy, trigeminal distribution numbness, and bitemporal hemianopia in 2 each (9%); and oculomotor palsy, facial palsy, optic perineuritis, dorsal midbrain syndrome, central vestibular nystagmus, and papilledema in 1 each (5%). Eight (36%) had a pre-existing diagnosis of sarcoidosis; however, in 14 (64%), the neuro-ophthalmic presentation led to the sarcoidosis diagnosis. Patients with a pre-existing sarcoidosis diagnosis were younger than those without this diagnosis (38.5 vs 50.1 years, P = 0.035). Brain MRI was abnormal in all but 1 case (95%). In patients without a pre-existing sarcoidosis diagnosis, all 7 tested for angiotensin converting enzyme (ACE) had normal values, and 75% of the 12 who had computed tomography (CT) chest had findings suggestive of sarcoidosis (86% of black patients vs 50% of white patients).

CONCLUSIONS

Patients with neurosarcoidosis may present initially with a neuro-ophthalmic manifestation, and this presentation may be more common in older patients. MRI usually is abnormal, although findings may be nonspecific. Serum testing for ACE is not helpful. Normal CT chest does not rule out underlying sarcoidosis, particularly in white patients.

Definition and Consensus Diagnostic Criteria for Neurosarcoidosis: From the Neurosarcoidosis Consortium Consensus Group

Importance

The Neurosarcoidosis Consortium Consensus Group, an expert panel of physicians experienced in the management of patients with sarcoidosis and neurosarcoidosis, engaged in an iterative process to define neurosarcoidosis and develop a practical diagnostic approach to patients with suspected neurosarcoidosis. This panel aimed to develop a consensus clinical definition of neurosarcoidosis to enhance the clinical care of patients with suspected neurosarcoidosis and to encourage standardization of research initiatives that address this disease.

Observations

The work of this collaboration included a review of the manifestations of neurosarcoidosis and the establishment of an approach to the diagnosis of this disorder. The proposed consensus diagnostic criteria, which reflect current knowledge, provide definitions for possible, probable, and definite central and peripheral nervous system sarcoidosis. The definitions emphasize the need to evaluate patients with findings suggestive of neurosarcoidosis for alternate causal factors, including infection and malignant neoplasm. Also emphasized is the need for biopsy, whenever feasible and advisable according to clinical context and affected anatomy, of nonneural tissue to document the presence of systemic sarcoidosis and support a diagnosis of probable neurosarcoidosis or of neural tissue to support a diagnosis of definite neurosarcoidosis.

Conclusions and Relevance

Diverse disease presentations and lack of specificity of relevant diagnostic tests contribute to diagnostic uncertainty. This uncertainty is compounded by the absence of a pathognomonic histologic tissue examination. The diagnostic criteria we propose are designed to focus investigations on NS as accurately as possible, recognizing that multiple pathophysiologic pathways may lead to the clinical manifestations we currently term NS. Research recognizing the clinical heterogeneity of this diagnosis may open the door to identifying meaningful biologic factors that may ultimately contribute to better treatments.