How can I differentiate between genuine hyperemesis gravidarum (HG) symptoms and factitious illness in a patient with persistent nausea, occasional dry heaving, significant weight loss, and ketonuria, despite unremarkable bloodwork?

This Patient Has Genuine Hyperemesis Gravidarum

Your patient's presentation is entirely consistent with hyperemesis gravidarum (HG), and questioning whether symptoms are "in her head" reflects a dangerous misunderstanding of this serious medical condition. The clinical picture—14-pound weight loss, ketonuria, orthostatic symptoms, and severe functional impairment—represents objective evidence of disease that cannot be fabricated or psychosomatic 1.

Why This is Genuine HG

Objective Clinical Markers Present

Your patient meets the diagnostic criteria for HG, which requires persistent vomiting, weight loss ≥5% of pre-pregnancy weight, dehydration, and ketonuria 1. She has:

• Significant weight loss (14 pounds represents >5% for most women) 1
• Ketonuria (objective metabolic evidence of starvation) 1, 2
• Orthostatic/presyncope symptoms (indicating volume depletion despite "normal" bloodwork) 3
• Severe functional impairment (14-18 hours bedbound daily) 1

The Vomiting Misconception

A critical pitfall: HG does not require frequent vomiting. The defining feature is intractable nausea that prevents adequate oral intake, not the act of vomiting itself 3, 1. Many HG patients experience predominantly nausea with minimal vomiting because they learn to avoid eating to prevent vomiting—this is adaptive behavior, not malingering 1. Your patient's pattern of extreme food aversions, inability to tolerate more than 2-3 bites, and reliance on Ensure on bad days demonstrates this exact phenomenon 3.

Why "Normal" Labs Don't Rule Out HG

The absence of concerning bloodwork is actually typical in early-to-moderate HG 3, 1. Electrolyte abnormalities often don't appear until dehydration is severe, and liver enzyme elevations (seen in 40-50% of HG cases) are not universal 3, 1. Ketonuria alone is sufficient metabolic evidence of inadequate caloric intake 2. The orthostatic symptoms indicate volume depletion that precedes laboratory abnormalities 3.

Differentiating HG from Factitious Illness

Features Supporting Genuine HG

• Consistent symptom pattern: Nausea rated 3-4 on good days, 8-9 on bad days with predictable triggers (food, smells) follows the typical HG course 1
• Appropriate coping mechanisms: Using Ensure drinks and eating small portions when tolerable represents rational adaptation, not attention-seeking 1
• Functional impairment: Being bedbound 14-18 hours daily with orthostatic symptoms reflects genuine physiologic compromise 1
• Weight trajectory: Progressive weight loss despite attempts to eat demonstrates involuntary caloric deficit 1

Red Flags for Factitious Illness (Absent Here)

• Inconsistent symptom reporting between visits
• Symptoms that improve when unobserved
• Resistance to effective treatments
• Secondary gain seeking (disability claims, attention)
• Discordance between reported symptoms and objective findings

Your patient shows none of these red flags. Her symptoms align perfectly with validated HG assessment tools like the PUQE score, which would rate her symptoms as severe 1, 2.

Immediate Management Required

First-Line Interventions

• Thiamine supplementation immediately: 100 mg daily minimum for 7 days, then 50 mg daily maintenance to prevent Wernicke encephalopathy 3, 1. Given her prolonged inadequate intake, she is at high risk for thiamine depletion 1
• Doxylamine-pyridoxine combination: First-line pharmacologic treatment, safe throughout pregnancy 1
• IV fluid resuscitation: Normal saline with potassium chloride guided by daily electrolyte monitoring, even if current labs appear "normal" 1, 2

Second-Line Options if First-Line Fails

• Metoclopramide: Preferred second-line agent with less sedation than alternatives 3, 1
• Ondansetron: Reserve for case-by-case basis, particularly effective but use cautiously before 10 weeks gestation 3, 1

Third-Line for Refractory Cases

• Methylprednisolone: 16 mg IV every 8 hours for up to 3 days, then taper over 2 weeks (maximum 6 weeks total) 3, 1
• Multidisciplinary involvement: Gastroenterology, nutrition, mental health support 3, 1

Critical Pitfalls to Avoid

The most dangerous error is dismissing HG as psychological or exaggerated. This leads to:

• Delayed treatment allowing progression to severe malnutrition 1
• Maternal complications including Wernicke encephalopathy (preventable with thiamine) 3, 1
• Fetal complications including low birth weight and preterm delivery 1
• Psychological trauma from medical gaslighting 3

HG has a 40-92% recurrence risk in subsequent pregnancies 1. Proper documentation and aggressive treatment now will inform future pregnancy management.

Severity Assessment

Use the PUQE score to objectively quantify severity rather than relying on subjective impressions 1, 2. Her symptoms (constant nausea rated 8-9 on bad days, inability to eat more than 2-3 bites, 14-pound weight loss, ketonuria, orthostatic symptoms) would score in the severe range 1.

This patient requires immediate escalation of care, not skepticism about symptom validity. Early aggressive intervention prevents progression to life-threatening complications 1.