The role of high-mobility group box-1 (HMGB-1) in the management of suspected acute appendicitis: useful diagnostic biomarker or just another blind alley?

Acute abdominal pain is one of the most frequent reasons for admitting patients to the emergency department for surgical evaluation. A wide number of differential diagnoses are available and their pre-test likelihood ratio varies according to the patients' age, gender, duration of symptoms and overall clinical context. While many patients with abdominal pain do not need to be admitted to the hospital wards and even fewer need eventual surgical intervention, the diagnosis of acute appendicitis remains one of the most frequently entertained differential in patients with abdominal pain. In fact, surgery for appendicitis is one of the most frequently performed operations in the Western world. As the authors of the current study point out, the high mobility group box-1 protein (HMGB1) has been known for many years. The study demonstrates in a small pilot that there is a difference in expression of HMGB1 between those with and those without appendicitis. However, is this difference clinically important? Clinically relevant results can only be documented through larger studies comparing its use and expression levels in both healthy subjects, subjects with abdominal pain for other reasons, patients with 'clear-cut' (histopathologically confirmed) appendicitis and in the difficult subgroup of patients with suspected appendicitis and equivocal symptoms.