Review Question - QID 106695

This patient’s clinical presentation, along with dermatologic and chest radiograph findings are highly suggestive of sarcoidosis. Of the choices provided, an increased CD4:CD8 in bronchioalveolar lavage (BAL) fluid is likely to be found.

Sarcoidosis is a noncaseating granulomatous disease that affects many organ systems. When it affects the lung, it typically causes restrictive lung disease. Patients with sarcoidosis can be completely asymptomatic, or have organ involvement. On chest imaging, bilateral hilar adenopathy is a classic feature. The etiology of sarcoidosis is unclear; however, it seems that genetically predisposed people may have a dysregulated immunologic response to an unknown antigen. T-cells play an important role in the development of sarcoidosis. CD4+ T-cells interact with antigen-presenting cells, eventually leading to IL-2 and IFN-y release, causing T-cells to expand, and macrophages to activate. Granuloma formation subsequently develops.

Wu and Schiff present a review on sarcoidosis. Clinical and radiologic findings, as well has histologic evidence of noncaseating granulomas, and exclusion of other granulomatous diseases play an important role in making the diagnosis. Even though corticosteroids is the mainstay of treatment, there is no well-defined way to optimally manage these patients.

Drent et al. present a review on bronchoalveolar lavage (BAL) in patients with sarcoidosis. Bronchioalveolar lavage (BAL) showing an elevated lymphocyte number along with a normal amount of neutrophils and eosinophils can be seen in many cases of sarcoidosis. CD4:CD8 ratio can be increased, normal, or decreased. BAL fluid analysis has decreased clinical relevance in assessing prognosis and treatment response.

Figure A shows an erythematous lesion termed erythema nodosum. This dermatologic finding is secondary to infection or inflammation, and thus is non-specific. These lesions can be painful, and are also tender to palpation. Figure B is a chest radiograph significant for bilateral hilar adenopathy, a common finding in patients with sarcoidosis.

Incorrect Answers:
Answer 1: An increased parathyroid hormone (PTH) would not be expected in sarcoidosis. Hypercalcemia is secondary to increased 1-alpha-hydroxylase activity in macrophages, which increases activated Vitamin D levels. Hypercalcemia would suppress PTH release directly.
Answer 2: Decreased serum angiotensin converting enzyme (ACE) level is incorrect. Though ACE levels are non-specific in sarcoidosis, about 75% of untreated patients would have their ACE levels elevated.
Answer 3: Caseating granulomas would be seen in diseases such as tuberculosis. Noncaseating granulomas is classic for sarcoidosis.
Answer 5: Ipsilateral facial muscle contraction post tapping the facial nerve describes Chvostek sign, a sign of hypocalcemia. One would expect hypercalcemia in sarcoidosis due to increased activated vitamin D levels.