Table 16.

Suggested diagnostic flowchart in some common conditions in high risk patients

ACE = angiotensin-converting enzyme; ANA = anti-nuclear antibodies; ANCA = anti-neutrophil cytoplasm antibodies; BNP = brain natriuretic peptide; CEA = carcinoembryonic antigen; CMV = cytomegalovirus; CT = computed tomography; EBV = Epstein-Barr virus; ENA = anti-extractable nuclear antigens; FMF = familial Mediterranean fever; HCV = hepatitis C virus; HHV = human herpesvirus; HIV = human immunodeficiency virus; IGRA = interferon-gamma release assay; MR = magnetic resonance; PCR = polymerase chain reaction; PET = positron emission tomography; spp = species; TB = tuberculosis; TRAPS = tumour necrosis factor receptor-associated periodic syndrome; TSH = thyroid stimulating hormone.

^aConsider storage of a sterile sample for further analyses.

^bSee viral pericarditis section—at present, these investigations have no therapeutic or prognostic implications.

IGRAs are whole-blood tests that can aid in diagnosing Mycobacterium tuberculosis infection. They do not help to differentiate latent TB infection from TB disease.