S. Stanga, MD
Where the dose goes decides whether ILIT works. The trials that showed benefit put the allergen inside an inguinal lymph node under ultrasound; the ones that disappointed often did not. For a practice adding ILIT, the ultrasound is not optional equipment.
Finding the node
Superficial inguinal nodes sit in the crease between hip and thigh and are easy to see with a linear probe. The aim is the cortex, not the hilum, with a fine needle and a slow push of 0.1 ml. Most practitioners describe a learning curve of a dozen procedures with someone experienced watching.
Observation
Systemic reactions have been rare in the published series, but the dose is given in a well-vascularised tissue, so the same observation period and anaphylaxis readiness as for subcutaneous immunotherapy apply. Listed practices report 30 to 60 minutes.
What to tell patients
A pinch, some gel, drapes for privacy, and a wait afterwards. Patients who expect a blood-draw level of discomfort are rarely surprised. Patients who expect nothing sometimes are.
S. Shah, MD