Assessment of conditions that are frequently missed and easily identified
| Clinical feature or abnormal test | Other features | Corroborative tests | Differential diagnoses |
|---|---|---|---|
| Serostis | Documented fever or arthropathy | CRP, FBC or genetic testing | Familial Mediterranean fever |
| Mucosal ulcers (oral/genital) | Arthropathy, pathergy or rash/EN | HLA-B51 | Behçet's disease |
| Sicca: oral/ocular | Arthropathy or chronic rash | Shirmer's test or auto-antibodies | Sjogren's syndrome |
| Osmotic symptoms | Weight loss or abdominal pain | Glucose, HbA1c or calcium | Diabetes or hypercalcaemia |
| Arthropathy | Photosensitivity, Raynaud's syndrome or rash | ANA, ENA, complement or ferritin | Lupus, adult Still's disease or Lyme disease |
| Urticaria | >48 hours or residual discolouration | ANA, anti-C1q Ab or complement | Urticarial vasculitis (HUVS) |
| Abdominal/pelvic pain | Dyspareunia, menorrhagia or infertility | Pelvic imaging or laparoscopy | Endometriosis or Crohn's disease |
| Extreme daytime somnolence | Snoring, obesity or airway issues | Specialist sleep study | Obstructive sleep apnoea |
| Lymphopenia | EN, lupus symptoms or infections | SACE, ANA or HIV testing | Sarcoid, lupus or HIV |
ANA = antinuclear antibodies; CRP = C-reactive protein; EN = erythema nodosum; ENA = extractable nuclear antigen; FBC = full blood count; HbA1c = glycated haemoglobin; HUVS = hypocomplementemic urticarial vasculitis syndrome; SACE = serum angiotensin-converting enzyme.