What is the differential diagnosis and management for a 12-year-old girl with a 3-month history of anorexia (lack of appetite), dizziness, nausea, vomiting (emesis), and abdominal pain?

Differential Diagnosis and Management for a 12-Year-Old Girl with 3-Month History of Anorexia, Dizziness, Nausea, Vomiting, and Abdominal Pain

This constellation of chronic symptoms in an adolescent girl requires systematic evaluation for eating disorders, gastroparesis, functional gastrointestinal disorders, and organic pathology, with eating disorders being the most critical diagnosis to identify given the profound impact on morbidity, mortality, and quality of life in this age group. 1

Priority Differential Diagnoses

Eating Disorders (Highest Priority)

• Anorexia nervosa (AN) is the leading consideration given the triad of lack of appetite, 3-month duration, and female adolescent presentation, as peak onset occurs in early to mid-adolescence 1
• DSM-5 criteria no longer require the 85% expected body weight threshold or amenorrhea, making diagnosis more inclusive 1
• Look specifically for: restriction of food intake leading to lower than expected body weight, intense fear of weight gain, body image distortion, and any compensatory behaviors (vomiting, excessive exercise, laxative use) 1
• Critical physical examination findings include: vital signs for bradycardia and hypotension (physiologic adaptations to malnutrition), assessment for hypothermia, and evaluation of weight trajectory 1
• Medical complications from rapid or significant weight loss can manifest as the presenting gastrointestinal symptoms 1

Gastroparesis

• Consider especially if there is postprandial fullness, early satiety, and vomiting of undigested food 1, 2
• Gastric emptying scintigraphy performed for at least 2 hours (preferably 4 hours) is the diagnostic standard, with the radioisotope cooked into the solid portion of the meal 1, 2
• Physical examination should assess for succussion splash (suggestive of delayed gastric emptying or gastric outlet obstruction) 1
• Important to note: symptoms correlate poorly with degree of gastric emptying delay, so testing is essential 2

Functional Dyspepsia

• Defined by Rome IV criteria as bothersome epigastric pain, burning, postprandial fullness, or early satiation without structural disease 2
• Diagnosis requires at least 12 weeks of symptoms in the last 12 months 1
• Upper endoscopy is mandatory to exclude organic pathology before making this diagnosis 1, 2

Cyclic Vomiting Syndrome (CVS)

• Characterized by stereotypical episodes of acute-onset vomiting with symptom-free intervals 2
• Prevalence approximately 2% in US adults, but increasingly recognized in adolescents 2
• Critical history element: Ask specifically about cannabis use, as it is associated with CVS in 47% of cases in systematic reviews 2
• Psychiatric comorbidity, younger age, and tobacco use are associated features 2

Organic Pathology Requiring Urgent Evaluation

Life-threatening conditions to exclude immediately:

• Upper gastrointestinal bleeding: Dark vomit suggests hematemesis; consider peptic ulcer disease, gastric malignancy 3
• Bowel obstruction: Assess for abdominal distention, absent bowel sounds, colicky pain, inability to pass gas/stool 2, 3
• Malignancy: Epigastric mass was found in a case series of 12-year-old girls with similar presentations 4
• Infectious causes: Miliary tuberculosis with meningitis has presented with abdominal pain, nausea, and weight loss in this age group 5

Systematic Diagnostic Approach

Essential History Elements

Timing and Pattern:

• Duration and frequency of symptoms (chronic vs. episodic) 2, 6
• Relationship to meals: postprandial symptoms suggest gastroparesis or functional dyspepsia 1, 2
• Stereotypical episodes suggest CVS 2

Gastrointestinal Specifics:

• Vomiting characteristics: color (dark suggests bleeding), content (undigested food suggests gastroparesis), volume 3
• Bowel movement pattern: constipation is common in eating disorders and functional disorders 1, 7
• Pain location and quality: diffuse vs. localized, constant vs. colicky 3

Critical Red Flags:

• Weight loss trajectory and intentionality 1, 3
• Compensatory behaviors: self-induced vomiting, laxative/diuretic use, excessive exercise 1
• Body image concerns and fear of weight gain 1
• Cannabis use (distinguishes cannabinoid hyperemesis syndrome from CVS) 2
• Hot water bathing behavior (pathognomonic for cannabinoid hyperemesis syndrome) 2

Psychosocial Assessment:

• Recent stressors, family history of suicide, anxiety, depression 8
• Dieting behaviors (strong predictor of both eating disorders and paradoxically, weight gain) 1
• Eating behaviors: eating too quickly, insufficient chewing, overeating 2

Physical Examination Priorities

Vital Signs and General Appearance:

• Blood pressure (orthostatic changes suggest volume depletion) 3
• Heart rate (bradycardia in eating disorders) 1
• Temperature (hypothermia in malnutrition) 1
• Weight and BMI percentile for age 1

Abdominal Examination:

• Inspection for distention 3
• Auscultation for bowel sounds and bruits (celiac artery compression syndrome) 1
• Palpation for masses, tenderness, peritoneal signs 3, 4
• Percussion for succussion splash 1
• Assess for ascites 1

Additional Findings:

• Digital ulcers and telangiectasia (scleroderma) 1
• Enlarged lymph nodes (malignancy) 1

Initial Laboratory and Imaging Studies

Mandatory Initial Labs:

• Complete blood count (anemia suggests bleeding or malignancy) 1, 3, 4
• Basic metabolic panel (electrolyte abnormalities in eating disorders, especially hyponatremia from water loading) 1, 8
• Liver chemistries 1
• Thyroid function (can mimic eating disorder symptoms) 1

Selective Testing Based on Clinical Suspicion:

• Antiendomysial antibodies (celiac disease) 1
• Lactic acid (if concerned about mesenteric ischemia) 3
• Stool studies if diarrhea present 1
• Pregnancy test in adolescent females 7

Imaging:

• Upper endoscopy with esophageal biopsy is indicated to exclude peptic ulcer disease, malignancy, eosinophilic esophagitis, and gastritis before diagnosing functional disorders 1, 2
• Abdominal radiograph if obstruction suspected 3
• CT abdomen/pelvis with IV contrast if peritoneal signs, suspected mass, or obstruction 3

Specialized Testing:

• Gastric emptying scintigraphy (4-hour study preferred) if gastroparesis suspected after excluding anatomic causes 1, 2
• Antroduodenal manometry if gastric emptying is normal but symptoms persist 1

Management Algorithm

If Eating Disorder Identified (Most Critical for Mortality/Morbidity)

Immediate Actions:

• Assess for medical instability requiring hospitalization: severe bradycardia, hypotension, hypothermia, electrolyte abnormalities, rapid weight loss 1
• Hospitalization is indicated if hemodynamic instability, severe malnutrition, or psychiatric crisis 1
• Multidisciplinary team involvement: medical provider, mental health professional, nutritionist 1

Outpatient Management:

• Family-based therapy is first-line for adolescents 1
• Cognitive behavioral therapy and nutritional rehabilitation 1
• Address comorbid anxiety and depression 1
• Avoid dieting interventions, as dieting increases risk of both eating disorders and paradoxical weight gain 1

If Gastroparesis Confirmed

Dietary Modifications (First-Line):

• Frequent smaller meals, replace solids with liquids (soups), low fat and fiber content 1
• Liquid diet for severe cases 1

Pharmacologic Management:

• Metoclopramide 10 mg three times daily before meals and at bedtime for at least 4 weeks is the only FDA-approved medication 1
• Counsel about black box warning for tardive dyskinesia, though risk may be lower than previously estimated 1
• Antiemetic agents for nausea: prochlorperazine, trimethobenzamide, promethazine, or 5-HT3 antagonists (ondansetron) 1
• Erythromycin as alternative prokinetic agent 1

Refractory Cases:

• Consider combining prokinetic agents 1
• Enteral feeding via J-tube for severe cases 1
• Gastric electrical stimulation 1
• Endoscopic botulinum toxin injection into pylorus 1

If Functional Dyspepsia Diagnosed

• Treat with dietary modifications and symptomatic over-the-counter therapy for mild cases 1
• Proton pump inhibitors or H2 blockers 1
• Cognitive behavioral therapy/hypnotherapy 1
• Address comorbid affective disorders 1

If Organic Pathology Found

Upper GI Bleeding:

• Immediate resuscitation with IV fluids, NPO status 3
• Blood transfusion if hemodynamic compromise 3
• Urgent gastroenterology consultation for endoscopy 3

Bowel Obstruction:

• Surgical consultation for peritoneal signs, complete obstruction 3
• IV fluids, nasogastric decompression 3

Malignancy:

• Oncology referral 3
• Staging and treatment planning 3

Common Pitfalls to Avoid

• Missing eating disorders by focusing solely on gastrointestinal workup: Always assess eating behaviors, body image concerns, and compensatory behaviors in adolescent females with chronic GI symptoms 1
• Performing gastric emptying studies <2 hours duration: These are inaccurate and lead to false negatives 1, 2
• Not controlling blood glucose during gastric emptying testing: Hyperglycemia delays gastric emptying and causes false positives 2
• Failing to ask about cannabis use: This is critical for distinguishing cannabinoid hyperemesis syndrome from CVS 2
• Diagnosing functional disorders without upper endoscopy: Mechanical obstruction and malignancy must be excluded first 1, 2
• Overlooking hyponatremia from water loading in eating disorders: This can cause neurologic complications 8
• Not accounting for medications affecting gastric emptying: Opioids, anticholinergics, and prokinetics alter test results 2
• Recommending dieting for weight concerns: This paradoxically increases risk of both eating disorders and weight gain 1