Carnett’s test for excluding intra-abdominal origins of abdominal tenderness

Interpretation of this study is difficult since the authors excluded patients with functional gastrointestinal disorders. I will continue to use Carnett’s sign as one vote among components of the evaluation of abdominal pain.

Methods

Patients and examiners

130 consecutive outpatients with abdominal tenderness. “Patients who had functional
gastrointestinal disorders such as functional dyspepsia or irritable bowel syndrome were excluded from the analysis because of the potential for comorbidity by psychiatric disorders.”

Two of 8 generalist physicians with a mean of 7 years in practice examined each patient. One examiner knew the patient’s medical history and one was blinded.

Description of the test

“After routine examination of the abdomen, the site of maximum
tenderness is determined. The patient is then asked to
contract the abdominal muscles by raising his/her head from
the examination table while the examiner continues to apply
pressure to the tender site. The test is positive if tenderness
becomes more severe or is unchanged. A positive test suggests
that the abdominal wall is the source of pain. On the
other hand, the test is negative when tenderness is reduced,
which suggests that the pain has an intra-abdominal source.”

Reference standard

Final diagnosis after clinical evaluation.

Results

Results are in the Figure. 86% of patients with abdominal wall or psychogenic pain had a positive test. 13% of patients with intra-abdominal causes of pain had a positive test.

The reproducibility was high, κ=0.81.

Citation

Takada T, Ikusaka M, Ohira Y, Noda K, & Tsukamoto T (2011). Diagnostic usefulness of Carnett’s test in psychogenic abdominal pain. Internal medicine (Tokyo, Japan), 50 (3), 213-7 PMID: 21297322