Clinical Evaluation of Inflammatory and Blood Parameters in the Workup of Pediatric Chronic Abdominal Pain

To investigate the additional value of blood parameters (hemoglobin, C-reactive protein, erythrocyte sedimentation rate) to anti-tissue transglutaminase (anti-tTG), fecal calprotectin, and Giardia lamblia when discriminating a functional from an organic cause in the clinical evaluation of children with chronic abdominal pain. This retrospective cohort study included patients (4-18 years of age) with abdominal pain for >2 months. Data on hemoglobin, C-reactive protein, erythrocyte sedimentation rate, anti-tTG, fecal calprotectin, alarm symptoms, and diagnosis were collected. We identified 853 patients, of whom 102 (12%) had an organic disorder. Sensitivity and the area under the curve of strategy 1 (fecal calprotectin, anti-tTG, G lamblia, blood parameters) were 90% (95% CI, 83-95) and 0.87 (95% CI, 0.81-0.93), respectively, compared with 88% (95% CI, 81-93) and 0.85 (95% CI, 0.79-0.91), respectively, for strategy 2 (fecal calprotectin, anti-tTG, G lamblia) (P = NS). In the presence of ≥1 alarm symptoms, the sensitivity of strategies 1 and 2 was 92% (95% CI, 83-96) and 92% (95% CI, 83-96), and the areas under the curve were 0.93 (95% CI, 0.89-0.98) and 0.90 (95% CI, 0.84-0.97) (P = NS). To distinguish between a functional and an organic cause for chronic abdominal pain, hemoglobin, C-reactive protein, and erythrocyte sedimentation rate can be left out from the clinical evaluation as they might have no additional diagnostic yield. However, caution should be taken not to miss extraintestinal infections (2%).