Table 1.
Role of laboratory tests used in the clinical management of Crohn’s disease.
| LABORATORY TEST | ROLE | COMMENT |
|---|---|---|
| CRP and ESR | Assessment of disease activity Monitoring disease activity Predicting disease course Monitoring response to therapy |
Used in clinical practice Objective measure of inflammation Cheap Low specifity |
|
Other acute phase-reactant: Orosomucoids Beta2microglobulin Sialic acid |
Assessment of disease activity | Not routinely available Potentially useful to integrate CRP |
| Fecal calprotectin | Assessment of disease activity Monitoring disease activity Predicting disease course Monitoring response to therapy |
A surrogate marker of intestinal inflammation in IBD related to endoscopy activity Discriminating IBD from irritable bowel syndrome Can be used to avoid invasive procedures Accuracy demonstrated in the assessment of response to anti-TNF therapy Increasingly use in clinical trials of novel therapies |
| Fecal lactoferrin | Assessment of disease activity Monitoring disease activity Predicting disease course Monitoring response to therapy |
A surrogate marker of intestinal inflammation in IBD Used in the assessment of response to anti-TNF therapy Less stable at room temperature, used in research |
| Complete blood cell count (WBC, Hb, platelets) | Assessment of disease activity Monitoring disease activity Identifying complications |
Routine evaluation of recurrence Diagnosis of intercurrent infections Diagnosis of anemia Monitoring of drug safety (thiopurines) |
| Serum iron, TIBC, transferrin, ferritin, Albumin, Vitamin B12, folate | Assessment of nutrional status Identifying complications |
Diagnosis of iron-deficiency anemia Evaluation of malnutrition and selective deficiencies |
| Anti-Saccharomyces cerevisiae antibodies (ASCA) Anti-ompc Anti-pseudomonas 12 Anti-flagellin |
Antibodies- anti serum microbial antigens more specific for Crohn’s disease | Discriminating Crohn’s disease from ulcerative colitis in colonic IBD High titres related to early surgery and complications |
| Intestinal fatty acid binding proteins (FABPs) | Plasma and urine marker that indicates intestinal damage | Evidence from research Not used in clinical practice |
| PGRN antibodies (PGRN-Abs) | Proinflammatory effects | Evidence from research Not used in clinical practice |
|
Virology studies: HBV Markers Anti-HCV Anti-HIV EBV status CMV-DNA Tuberculin Skin Test (TST) Quantiferon-TB |
Screening candidates to biologics and thiopurines Assessment of refractory colitis |
Recommended by clinical practice guidelines to prevent viral infections and latent TB reactivations CMV superinfection related to refractoriness of acute colitis EBV negative subjects can develop EBV-related lymphoproliferative dysorders |
| Anti-TNF trough levels and antibodies Thiopurine metabolites |
Therapeutic drug monitoring | Approach to personalized therapy and safety and costs optimization strategy |
| TPMT (thiopurine polymorphisms) testing | Selecting candidates to thiopurines | Pharmacogenomic approach Use in clinical practice debated |