Abstract Introduction Sarcoid-associated pleural effusions (SAPE) are a rare extrapulmonary manifestation of sarcoidosis, estimated to occur in approximately 1-3% of patients1. When present, pleural effusions may be a feature of the initial presentation and ultimately lead to the diagnosis of sarcoidosis. Lymphocytic exudative effusions with a high concentration of protein are typical of SAPE2. We present a case of this rare diagnosis and highlight recently proposed clinical diagnostic criteria in the absence of pleural biopsy. Case Description A 68-year-old black male without significant past medical history presented to his primary care physician with 2 months of cough, dyspnea, weight loss, and night sweats. He was a never-smoker, had no significant occupational exposures, and had no recent travel. A chest radiograph revealed a large right-sided pleural effusion (Figure 1). Diagnostic thoracentesis revealed a lymphocyte-predominant (48%) effusion, with a protein level 6.5 g/dL (serum protein 8.0 g/dL), and LDH level of 441 U/L (Serum LDH 159 U/L). Gram stain and culture were not consistent with infection, and cytology was negative for malignant cells. Workup for tuberculosis was negative, including three negative AFB sputum cultures, a negative QuantiFERON Gold, and an unremarkable pleural adenosine deaminase level. Computed tomography of the chest after drainage revealed multiple enlarged mediastinal and bilateral hilar lymph nodes, a moderate right lower lobe consolidation, and diffuse micronodularity in a perilymphatic distribution (Figures 1.2). Bronchoalveolar lavage of the right lower lobe was lymphocyte predominant (29%). An endobronchial ultrasound-guided (EBUS) fine-needle aspiration of hilar lymph nodes revealed well-formed, noncaseating granulomas, confirming the diagnosis of sarcoidosis. A diagnosis of SAPE was made. The patient was started on daily prednisone without recurrence of the effusion. Discussion SAPE is an uncommon manifestation of sarcoidosis. Although non-caseating granulomas on pleural biopsy are required for the definitive diagnosis of SAPE, Chopra et al. have proposed clinical diagnostic criteria derived from a case series of 70 patients1. The four proposed criteria are: 1) diagnosis of sarcoidosis at an extra-pleural site, 2) pleural fluid cell count 500 with 50% lymphocytes, 3) exclusion of alternative diagnoses, and 4) resolution of effusion with steroids. The postulated mechanism driving SAPE is similar to that of other infiltrative diseases, in which pleural involvement leads to increased capillary permeability and leakage of protein-rich fluid3. Because SAPE shares many overlapping characteristics with other causes of lymphocytic effusions, particularly tuberculous effusions, clinicians should consider SAPE a diagnosis of exclusion4. This abstract is funded by: None
Nus et al. (Fri,) studied this question.