How should I evaluate and manage a 2‑year‑old female with sudden epigastric pain and vomiting after coconut water ingestion, vomiting that lasted three days and stopped, intermittent fever now resolved, currently drinking only small sips, urinating, yellow vomitus, and persistent epigastric discomfort?

Evaluation and Management of a 2-Year-Old with Epigastric Pain and Vomiting After Coconut Water Ingestion

Most Likely Diagnosis

This clinical presentation is most consistent with viral gastroenteritis that has already begun to resolve, though food protein-induced enterocolitis syndrome (FPIES) triggered by coconut water must be considered given the temporal relationship to ingestion. 1, 2

The key distinguishing features supporting viral gastroenteritis include:

• Self-limited course with vomiting stopping by day 4 1
• Non-bilious (yellow) vomitus without blood 1, 3
• History of intermittent fever (now resolved) 4
• Child maintaining some oral intake and urine output 4
• Absence of red flag signs (no bilious vomiting, no altered mental status, no severe dehydration, no bloody emesis) 3, 1

However, FPIES remains in the differential because:

• Vomiting began 1-4 hours after coconut water ingestion (timing consistent with acute FPIES) 2
• Repetitive vomiting over 3 days 2
• Complete resolution of vomiting after presumed elimination of trigger 2

Critical Red Flags to Exclude NOW

Immediately assess for these concerning features that would change management urgency:

• Bilious (green) vomiting - indicates intestinal obstruction requiring immediate surgical evaluation 1, 3
• Signs of severe dehydration (>10% deficit): sunken fontanelle, poor skin turgor, dry mucous membranes, <4 wet diapers in 24 hours, capillary refill >2 seconds 1, 4
• Abdominal distension, peritoneal signs, or palpable mass - suggests surgical pathology 1, 3
• Hemodynamic instability (tachycardia, hypotension) - requires IV resuscitation 5, 4
• Altered mental status or lethargy - concerning for metabolic derangement or CNS pathology 3, 2

Immediate Clinical Assessment

Hydration Status Evaluation

Perform a focused physical examination to determine dehydration severity using these specific parameters: 4, 1

• Mild dehydration (3-5% deficit): slightly dry mucous membranes, normal capillary refill
• Moderate dehydration (6-9% deficit): dry mucous membranes, decreased skin turgor, capillary refill 2-3 seconds
• Severe dehydration (≥10% deficit): very dry mucous membranes, tenting skin, capillary refill >3 seconds, sunken fontanelle, minimal urine output

Given that this child is drinking small amounts and urinating, she likely has at most mild dehydration. 4

Abdominal Examination Specifics

Palpate carefully for: 1, 3

• Epigastric tenderness severity and exact location
• Right lower quadrant tenderness (appendicitis can initially present with periumbilical/epigastric pain before localizing) 1
• Abdominal distension or masses
• Peritoneal signs (guarding, rebound tenderness)

The absence of these findings supports a non-surgical diagnosis. 1

Diagnostic Approach

When to Order Laboratory Tests

Laboratory testing is NOT routinely needed if: 3, 4

• Physical exam shows no/mild dehydration
• No red flag signs present
• Viral gastroenteritis is the likely diagnosis

Order labs (electrolytes, renal function, blood gas) ONLY if: 3

• Moderate to severe dehydration present
• Red flag signs identified
• Concern for metabolic derangement

When to Order Imaging

Imaging is NOT indicated in this case because: 1

• Vomiting is non-bilious
• Abdomen is soft and non-tender
• No signs of obstruction
• Self-limited course

Abdominal imaging would be indicated if: 1, 3

• Bilious vomiting develops
• Abdominal pain worsens or localizes to RLQ
• Peritoneal signs develop
• Concern for surgical pathology

Management Plan

Immediate Hydration Management

Administer oral rehydration solution (ORS) in small, frequent volumes (5 mL every 1-2 minutes initially using a spoon or syringe) to replace ongoing losses. 5, 4

Replace each vomiting episode with 10 mL/kg of ORS. 6

Advance to regular diet as tolerated - there is no need to restrict foods once vomiting has stopped. 4

Antiemetic Consideration

Ondansetron is NOT indicated in this case because: 6, 3

• Vomiting has already stopped
• Child is tolerating small amounts orally
• Antiemetics are generally not indicated for routine viral gastroenteritis in young children

Ondansetron (0.15-0.2 mg/kg oral, maximum 4 mg) would only be considered if: 6, 5, 3

• Persistent vomiting prevents any oral intake
• Moderate dehydration with inability to tolerate ORS

FPIES-Specific Management

If FPIES is suspected, eliminate coconut and coconut products from the diet completely and observe for symptom resolution. 2, 1

Key features that would strengthen FPIES diagnosis: 2

• Complete symptom resolution within days of coconut elimination
• Recurrence of vomiting 1-4 hours after re-exposure to coconut
• Absence of IgE-mediated symptoms (no urticaria, wheezing, or angioedema)

Formal oral food challenge (OFC) would be needed to confirm FPIES diagnosis but should only be performed in a supervised medical setting with IV access available, as reactions can cause hypotension and shock. 2

Disposition and Follow-Up

Safe to Manage at Home IF:

• No/mild dehydration
• Tolerating small amounts of fluids
• Producing urine
• No red flag signs
• Reliable caregiver with ability to return if worsens

Return Immediately or Call If: 1, 6

• Vomiting becomes bilious (green) or projectile
• Blood appears in vomit or stool
• Fewer than 4 wet diapers in 24 hours
• Abdominal pain worsens or localizes to right lower quadrant
• Child becomes lethargic or difficult to arouse
• Fever returns or increases
• Unable to tolerate any oral fluids
• Signs of dehydration develop (dry mouth, no tears, sunken fontanelle)

Follow-Up in 24-48 Hours to:

• Reassess hydration status and weight (poor weight gain would elevate concern for GERD or other chronic pathology) 6, 1
• Confirm complete resolution of symptoms
• Discuss FPIES further if symptoms recur with coconut re-exposure

Common Pitfalls to Avoid

Do not dismiss the coconut water temporal relationship - while viral gastroenteritis is more common, FPIES can present identically and requires dietary elimination. 2, 1

Do not assume appendicitis is ruled out by initial soft abdomen - periumbilical/epigastric pain in a 2-year-old warrants serial abdominal examinations over 12-24 hours, as appendicitis can evolve. 1

Do not use antidiarrheal or antimotility agents - these are contraindicated in young children with gastroenteritis and shift focus away from appropriate fluid therapy. 6

Do not restrict breastfeeding or formula - continue full-strength feeds as tolerated once vomiting stops. 6