Apparent neurosarcoidosis in a context of chronic beryllium disease

Background Chronic beryllium disease (CBD) is a granulomatous disease mimicking sarcoidosis. While the etiology of sarcoidosis remains elusive, CBD is caused by beryllium exposure, which leads to T-cell activation in predisposed individuals. Sensitization to beryllium can be diagnosed with high specificity by the beryllium lymphocyte proliferation test (BeLPT). Extra-pulmonary involvement is common in sarcoidosis, whereas CBD is mostly confined to the lungs. Central nervous manifestation of CBD has not been reported convincingly.

Case history In 2017, a 47 year old male presented with dyspnea and severe resting hypoxemia. Diffuse pulmonary nodules were found on chest-computed tomography, lymphocytic (46%) alveolitis and CD4/CD8 ratio of 5.3 in bronchoalveolar lavage (BAL) and non-necrotizing granulomas on lung biopsy. Sarcoidosis was diagnosed and corticosteroid treatment initiated. After tapering, the patient developed new onset hemiparesis and dysarthria. A diagnosis of neurosarcoidosis was made by multidisciplinary discussion based on highly suggestive cerebral imaging and cerebrospinal fluid lymphocytosis with a CD4/CD8 ratio in the upper range of normal (4.1). The course of the disease was marked by recurring flares and disease progression despite multiple lines of therapy. Work-up in our department suggested occupational beryllium exposure and demonstrated beryllium sensitization in BeLPT of peripheral blood and BAL cells even under immunosuppression.

Discussion We report a case of a pulmonary granulomatosis fulfilling criteria of CBD in a patient also presenting manifestations consistent with neurosarcoidosis. Although the cooccurrence of two distinct granulomatous diseases is unusual, there is no sufficient evidence to date to postulate central nervous involvement of CBD. Suspicion of extrapulmonary sarcoidosis should not per se exclude the possibility of CBD in a compatible occupational context. Our threshold to perform BeLPT should be low in such cases.

Publication History

Article published online:
09 March 2023