Anchors Away

A CLINICAL PROBLEM-SOLVING article by Carolyn Calfee from University of California, San Francisco.
A 50-year-old Asian woman presented with a papulonodular, erythematous rash on her legs below the knees. The skin lesions were nontender and nonpruritic and were accompanied by paresthesias.
A biopsy of one of the skin lesions showed granulomatous dermatitis. Stains and cultures for acid-fast bacilli and fungal organisms were negative. On the basis of the clinical and histopathological findings, a diagnosis of sarcoidosis was made by the patient's physician.
A chest radiograph reportedly revealed scattered nodules and increased interstitial markings that were considered to be consistent with sarcoidosis. Three months later, shortly before her appointment with the pulmonologist, dyspnea on minimal exertion, hoarseness, and dysphagia with both solids and liquids developed.
In this case, several findings support the diagnosis of sarcoidosis. None of these findings, however, are specific enough to be considered diagnostic of sarcoidosis.
Why did the physicians initially involved in this case settle on a diagnosis of sarcoidosis? They most likely fell prey to two types of cognitive bias: the availability and anchoring heuristics.
The clinicians initially accepted the diagnosis and were falsely anchored to it from that point onward.

最終診断は、リンパ腫様肉芽腫症(lymphomatoid granulomatosis)だが、Discussantはサルコイドーシスにアンカリングされてしまった。