ED Sonographic Score Helps Rule in or Exclude Acute Cholecystitis

By Marilynn Larkin

January 21, 2021

NEW YORK (Reuters Health) - A bedside scoring tool could help identify or rule out sonographic acute cholecystitis (SAC) in the emergency department (ED), researchers say.

The study builds on previous work and "defines a way to potentially rule in or out acute cholecystitis at the time of initial presentation, using only history, physical exam, and bedside ultrasound," Dr. Andrew Liteplo of Massachusetts General Hospital in Boston told Reuters Health by email.

"While mid-range scores may be indeterminate and thus require additional work-up, a low (<2) Bedside SAC Score effectively rules out acute cholecystitis and a high (7 or greater) score essentially rules it in," he said.

"Proficiency in performance and interpretation of point-of-care ultrasound is important," he noted, "but this is a skill that emergency physicians and doctors in other specialties learn during training and incorporate routinely into daily clinical practice."

The prospective, observational validation study published in the American Journal of Emergency Medicine included 153 patients (mean age, 44; 34% men overall) with suspected acute cholecystitis.

To calculate the SAC score, researchers combined three symptoms and signs - post-prandial symptoms, right upper-quadrant tenderness, and Murphy's sign - and two sonographic findings (gallbladder wall thickening and presence of gallstones). The diagnosis was confirmed from chart review or patient follow-up up to 30 days after the initial assessment.

Surgical pathology was used to confirm the diagnosis in patients who underwent surgery.

Using a previously defined cutoff of 4 or more, the Bedside SAC Score had a sensitivity of 88.9% and a specificity of 67.5% overall. A score of < 2 had a 100% sensitivity and 35% specificity. A score of 7 or more had a sensitivity of 44.4% and specificity of 95.7%.

Dr. Liteplo said, "While larger studies to confirm findings could provide additional external validity, this score can already be used in settings where healthcare providers have experience performing and interpreting their own ultrasound."

Dr. Thomas Costantino, Professor of Clinical Emergency Medicine and Director of the Emergency Medicine Ultrasound Fellowship at the Lewis Katz School of Medicine at Temple University in Philadelphia, commented in an email to Reuters Health that the score "could have utility in the ED."

"It seems especially useful in ruling out cholecystitis in patients with a low score without the need for further laboratory tests or radiologic imaging," he said. "This could save patients both time and unnecessary venipuncture."

"A higher score, whether >4 or >7, had less value and would be unlikely to spare patients either further imaging or venipuncture," he added. "However, the study is small (only 36 patients had cholecystitis) and larger studies would have to be done to corroborate these findings."

SOURCE: https://bit.ly/2XZvtH6 American Journal of Emergency Medicine, online January 4, 2021