Diagnosis of Acute Gouty Arthritis Obscured by Anchoring Bias

a. yes
b. no
c. unknown but likely

Anchoring bias fits the general umbrella of diagnostic errors. Diagnostic errors include diagnoses that were missed, incorrect or delayed.⁵ Unfortunately, these errors are not usually detected until patients suffer worsening consequences of their disease process, which include hospitalization or even death. Efforts have been made to identify errors by pinpointing possible trigger events. The limitations of managing complex patients in the out­patient setting heighten the risk of suffering a diagnostic oversight.

Question 7

What are ways physicians can help target when a previous diagnostic error has been made? (Multiple answer choices may be correct.)

a. review medications
b. identify unusual patterns of care
c. identify frequent hospitalizations and/or ED visits
d. review most common malpractice claims
e. utilize more laboratory and invasive techniques

Many studies have been performed to help identify and address diagnostic errors in routine outpatient practice. Most errors involve the breakdown of processes related to the patient–practitioner clinical encounter.⁶ Thus, it is important to prevent medical error by ensuring proper classification of symptoms and, therefore, diagnoses. By reviewing medications and identifying unusual patterns of care, such as frequent physician visits and/or hospitalizations, physicians can start to analyze diagnostic or medical errors.

The question can be asked, “At what point should one begin to consider alternative diagnoses if multiple treatment modalities have failed?”

In this case, the patient’s comorbidities made it especially difficult to manage medications because, although he was treated with several disease-modifying anti-rheumatic agents, some thera­peutic failures were attributed to his under­lying multi-organ disease. Methotrexate was stopped secondary to elevated liver enzymes from chronic alcohol use, hydroxychloroquine stopped secondary to worsening uveitis, tocilizumab stopped in the context of neutropenia and infliximab stopped in the setting of congestive heart failure.

It is important to keep the list of differential diagnoses broad and to limit anchoring bias.

Discussion

Gout affects multiple organ systems, most commonly joints but also skin, soft tissue and kidneys.⁷ In this case, the patient, who had a known diagnosis of RA, presented with arthritis and fevers; however, secondary to confounding comorbidities, it was only after undergoing multiple, highly invasive procedures and a prolonged hospital course that a diagnosis of gouty arthritis was made.

Gout is the most common form of inflammatory arthritis with a prevalence of 5% in the U.S., and is characterized by swollen, erythematous & tender joint(s).

This case highlights the prevalence of anchoring bias in medicine and the pitfalls that prevent us from formulating thorough differentials. This exercise expands on the concept of premature closure or the failure to consider alternative diagnoses after an initial impression is formed.⁸ In anchoring bias, there may be a continued fixation over the initial diagnostic impression in the face of other compelling data.