A 6-year-old male fully vaccinated with no chronic medical conditions presents with abdominal pain and emesis for the past 48 hours.  Over the past year, the patient has had intermittent episodes of abdominal pain and emesis, typically self-resolving within a few hours. Two days ago, after eating, he developed intense abdominal pain and non-bloody but “greenish” emesis. Mom thought it might have been one of his usual episodes but he was screaming out in pain and kept vomiting. The family visited the ED, where an abdominal XR revealed “Relative paucity of bowel gas within the right lower quadrant, otherwise no dilated bowel loops or pathologic air-fluid levels. Overall mild to moderate colonic stool volume.” CBC, CMP, and UA were unremarkable. He was treated with Zofran and an enema after which he reportedly had a large stool output and felt better. Mom states that after they left the hospital he continued vomiting consistently, prompting a return to the ED 24 hours later. Denies headache, confusion, AMS, abnormal gait, weakness, and fever. No longstanding history of constipation but has not stooled since the enema.

No PMH, PSH, Daily medications, Allergies, or relevant family history

Physical Exam:
VS: T 36.8, HR 80, RR 20, BP 112/76, SpO2 98%

General:  awake, alert, interactive, talkative, answers questions appropriately. intermittently clutches his abdomen and cries out, but is distractible.
Skin:  Warm.  dry.  
Head:  Normocephalic.  atraumatic.  
Eye:  Pupils are equal, round and reactive to light.  normal conjunctiva.  no discharge.  
Ears, nose, mouth and throat:  Oral mucosa moist.  No pharyngeal erythema or exudate.  
Cardiovascular:  Regular rate and rhythm.  No murmur.  Normal peripheral perfusion.  normal perfusion with cap refill <2 seconds, not flash, strong 2+ radial pulses.  
Respiratory:  non-tachypneic, no increased work of breathing, no retractions or accessory muscle use, normal aeration bilaterally without wheeze, crackles or other adventitious sounds
Gastrointestinal:  abdomen is soft and compressible with no masses palpated, no involuntary guarding, patient has diffuse tenderness to palpation and cries out when palpate in all areas. You observe the patient have a medium volume of emesis that is light greenish in color.
Neurological:  Alert.  No focal neurological deficit observed.  
Genitourinary:  testicles descended bilaterally; normal cremasteric reflex bilaterally; no tenderness to palpation of bilateral testicles or penis; penis circumcised normal in appearance

Abdominal US showed: Small bowel to small bowel intussusception is seen in the right lower quadrant measuring 2.9 x 2.4 x 1.5 cm. Reactive enlarged mesenteric lymph nodes are seen in the right lower quadrant . Normal sonographic appearance of the appendix

AXR reveals: Nonobstructive bowel gas pattern with mild colonic stool volume. No significant interval change from most recent comparison radiographs.

CBC is unremarkable, CMP reveals only a slightly increased BUN from yesterday, urine unremarkable with only increased spec gravity.

A PO challenge was attempted however the patient had another episode of emesis – not clear if it was green as he discarded the emesis bag. The patient was made NPO with IVF and admitted to the hospitalist service. No significant changes to the exam. Patient was intermittently crying out in pain, but at other times calm and watching TV or napping.