January Case #3: Abdominal Pain

25 y/o WM presents to the ED with complaints of periumbilical abdominal pain for 2 days, which is now moved to his RLQ. He denies N/V, F/C.

PMHx: Asthma
PSHx: none
Meds: none
Allergies: NKDA
Soc Hx: denies ETOH, drugs or tobacco

PE:
VS: BP 125/70, P 90, R 18, T 98.5
GEN: WNWD, WM, NAD
CHEST: CTA B, nonlabored
CV: RRR, no M/R/G
ABD: TTP RLQ, garding, no rebound, +BS, guiac-
EXT: no C/C/E

Bedside ultrasound is performed:


What is the diagnosis?

What is the hyperechoic structure within the lumen?


Special thanks to Ruben Font for submitting this case!