Main performed investigations
| First admission | Outpatient | Second admission | Third admission | |
| From symptom onset | 2–3 weeks | 9–12 weeks | 13 weeks | 15 weeks |
| Haematology tests | ||||
| Leucocytes (×109/L) | 10.8 | 12.4 | 6.9–10.0 | 10.6–13.0 |
| Haemoglobin (g/L) | 7*7 | 10.7 | 10.9 | 8.2 |
| MCV (fL) | 63.2 | 69.7 | 70.8 | 71.7 |
| ESR (mm/hour) | 80 | |||
| Biochemistry tests | ||||
| CRP (mg/L) (N <3) | 137 | 124–138 | 243 | |
| Ferritin (ng/mL) | 146 | 553 | 541 | |
| Fe (µg/dL) | 14 | 22 | 13 | |
| TSI (%) | 6.3–9.2 | 11.2 | 10.1 | |
| LDH (IU/L) (N 135–235) | 141–164 | |||
| TSH (µU/mL) | 1.89 | |||
| ANAs | + (citoplasmic pattern) | |||
| ENAs | ++ | |||
| Anti-SSA Ab | +++ | |||
| ANCAs | – | |||
| C3 (mg/dL) (N 75–140) | 163 | 151 | ||
| Faeces | ||||
| Calprotectin (ng/g) (N <30) | 274 | 2411 | ||
| Occult blood (×3) | – | |||
| Urinalysis | N | N | ||
| Microbiology tests | ||||
| Serologies | – | |||
| Leishmania PCR | – | |||
| Blood, urine cultures | – | – | – | |
| Stool culture | – | Campylobacter jejuni | ||
| IGRA | – | |||
| Clostridium difficile Ag | – | |||
| Image studies | ||||
| Chest X-ray | N | |||
| Abdominal ultrasound | N | |||
| Echocardiography | Mild pericardial effussion | Mild pericardial effusion/aortic regurgitation | ||
| Gastrointestinal transit | N | |||
| Abdominal CT | N | |||
| Brain MRI | Left maxillary sinusitis | Left maxillary sinusitis | ||
| Intestinal MRI | Thickening of the terminal ileum | |||
| MR angiography | Inflammation of the wall of the thoracic and abdominal aorta and supra-aortic trunks | |||
| PET–CT | Increase in metabolism in thoracic and abdominal aorta | |||
| Colonoscopy | Macroscopy: minimal changes in the terminal ileum Microscopy: compatible with Crohn’s disease |
*IV iron administered.
ANA, antinuclear antibody; ANCA, antineutrophil cytoplasmic antibody; CRP, C reactive protein; ENA, extractable nuclear antibody; ESR, erythrocyte sedimentation rate; IGRA, interferon-gamma release assay; LDH, lactate dehydrogenase; MCV, mean corpuscular volume; MR, magnetic resonance; N, normal; PET, positron emission tomography; TSH, thyroid-stimulating-hormone; TSI, transferrin saturation index.