Child health
AKT · Child health/Infection & rashlow yield
Mesenteric adenitis
Reactive mesenteric lymphadenitis (often post-viral)
Overview
Self-limiting inflammation of mesenteric lymph nodes, often following a viral URTI, causing abdominal pain that mimics appendicitis — a diagnosis of exclusion once appendicitis is ruled out.
Recognise
- Central/right iliac fossa abdominal pain, often after/with a URTI
- Higher fever, less localised tenderness than appendicitis
- Associated coryza/sore throat, cervical lymphadenopathy
Red flags
- Do not miss appendicitis — if in doubt, observe/image/operate
Differentials & how to tell them apart
Appendicitisprogressive, localised RIF tenderness with guarding, anorexia — the must-not-miss; surgical
Gastroenteritisdiarrhoea/vomiting predominate
Intussusceptioncolic, target sign on USS
Investigations
Clinical; USS may show enlarged mesenteric nodes with a normal appendix. Bloods often less deranged than appendicitis.
Management
Supportive (self-limiting); ensure appendicitis is excluded
- 1Supportive care once appendicitis is excluded — analgesia, fluids, safety-net.Gate: If appendicitis cannot be confidently excluded → observe, re-examine, image or operate
- 2Reassure; resolves spontaneously.
Supportive — analgesia, fluids; no specific treatment
Key points
A diagnosis of exclusion — the priority is not missing appendicitis. Recent/concurrent URTI supports it.
Monitor & prognosis
Re-examine if not settling; safety-net for appendicitis.
Self-limiting.
Source: Paediatric surgery; NICE