Isolated dysphagia unmasking bulbar neurosarcoidosis and pulmonary sarcoidosis

Comparison of lung microbiota between antineutrophil cytoplasmic antibody-associated vasculitis and sarcoidosis

Microbial involvement in the pathogenesis have been suggested in both antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and sarcoidosis, both of which have lung involvement. However, exhaustive research to assess the bacteria in the lung in AAV and in sarcoidosis have not been performed. We sought to elucidate the distinct dysbiotic lung microbiota between AAV and sarcoidosis. We used 16S rRNA gene high-throughput sequencing to obtain the bacterial community composition of bronchoalveolar lavage fluid (BALF) in patients with AAV (n = 16) compared to patients with sarcoidosis (n = 21). The patients had not undergone therapy with immunosuppressive medication when their BALF was acquired. No difference was observed in α-diversity between patients with AAV and patients with sarcoidosis when using all the detected taxa. We defined the taxa of the oral cavity by using the data of oral microbiota of healthy individuals from the Human Microbiome Project (HMP). The analysis using only oral taxa made the difference in α-diversity between AAV and sarcoidosis clearer compared with those using all the detected taxa. Besides, the analysis using detected taxa except for oral taxa also made the difference in α-diversity between AAV and sarcoidosis clearer compared with those using all the detected taxa. A linear negative relationship between the α-diversity and Birmingham vasculitis activity score (BVAS) was detected in the AAV group. The observed p-value for the effect of the disease groups on the ß-diversity was small while the effect of other factors including sex and smoking status did not have small p-values. By excluding oral taxa from all the detected taxa, we found a cluster mainly consisted of sarcoidosis patients which was characterized with microbial community monopolized by Erythrobacteraceae family. Our results suggested the importance of considering the influence of oral microbiota in evaluating lung microbiota.

[A patient with neurosarcoidosis presenting with easy falling and dysphagia]

A 68-year-old woman was referred to our hospital for progressive dizziness, gait disturbances and weight loss for 18 months. The patient was alert and showed dysphagia and a marked tendency to fall backward. Electronystagmography showed bilateral vestibular dysfunction and audiometry showed right sensorineural hearing disturbance. Cerebrospinal fluid exam showed mononuclear pleocytosis and elevated protein levels. On ¹⁸F-FDG PET/CT, abnormal uptake was observed in the mediastinal lymph nodes, from which biopsy specimens were obtained. Histological findings showed non-caseous granuloma and a diagnosis of bilateral vestibulocochlear, glossopharyngeal and vagal nerve palsies due to neurosarcoidosis was made. Steroid therapy resulted in improvement in her clinical symptoms. Neurosarcoidosis should be included in the differential diagnosis of patients showing progressive easy falling and dysphagia.

Isolated Bulbar Palsy: A Rare Presentation of Neurosarcoidosis

Sarcoidosis, which is a non-caseating granulomatous chronic inflammatory disease, can affect virtually any organ system, including the central nervous system (CNS). Very rarely, patients may present solely with neurosarcoidosis. It commonly presents with unilateral or bilateral seventh nerve palsy. Rarely it can present as dangerous progressive bulbar palsy and is a diagnostic and clinical challenge. We present a case of sarcoidosis with a unique presentation of isolated bulbar palsy. A 38-year-old male presented to the emergency with a sudden onset of dysphonia followed by dysphagia for both solids and liquids for one week and 5 kg weight loss in two months. The rest of the CNS exam was unremarkable. On labs, he had hypercalcemia and suppressed parathyroid hormone (PTH) intact. Detailed radiological investigations, lab tests, and lymph node biopsy helped confirm the diagnosis of neurosarcoidosis. The patient did not respond to first-line steroid therapy and hence received intravenous immunoglobulin (IVIG) subsequently with adequate response and complete neurologic recovery, confirmed by a follow-up visit.