Clinical Vignette
Patient: "Mr. G," 45-year-old IT manager, self-referred after his wife threatened to leave if he 'doesn't stop Googling diseases.'
Chief Concern: "I'm constantly terrified that I have cancer or a brain tumor. I check my body for lumps every morning. I've had 4 MRIs in 2 years and 12 blood panels. Every test is normal but I can't believe it. I know it sounds crazy but the fear won't stop."
History of Present Illness: Mr. G reports a 4-year preoccupation with the possibility that he has an undiagnosed serious illness, primarily cancer or a brain tumor. His concern began after a coworker was diagnosed with pancreatic cancer. Despite no abnormal physical findings, he performs daily self-examinations (checking for lumps, examining moles, monitoring bowel habits). He researches symptoms online for 2-3 hours daily. He has sought medical reassurance extensively: 4 MRIs (brain and body), 12 comprehensive blood panels, 2 colonoscopies (both normal), 3 dermatology visits, and 2 cardiology consultations. Reassurance from negative results lasts approximately 2-3 days before anxiety returns. He reports minimal actual physical symptoms: occasional headaches and fatigue, which he attributes to his anxiety and sleep disruption rather than to illness. His primary complaint is the ANXIETY about illness, not the physical sensations themselves. He acknowledges his body feels 'mostly fine' but cannot stop the fear that something is being missed.
Medical History: No significant medical conditions. All investigations normal.
Mental Status Exam: Well-groomed. Cooperative. Speech normal. Mood 'terrified.' Affect anxious. Thought content: preoccupied with illness despite normal investigations. No psychotic symptoms. No depressive symptoms. Insight partial: recognizes his behavior is excessive but cannot control it.
Step 1: Illness Anxiety Disorder DSM-5-TR Criteria
Criterion A: Preoccupation with having or acquiring a serious illness.
Four-year preoccupation with cancer and brain tumors. Daily self-examinations. 2-3 hours daily online symptom research. MET.
Criterion B: Somatic symptoms are not present or, if present, are only mild in intensity.
Reports occasional headaches and fatigue only. He attributes these to anxiety and poor sleep, not to illness. Physical symptoms are minimal and not the primary clinical concern. MET — somatic symptoms are mild.
Criterion C: There is a high level of anxiety about health, and the individual is easily alarmed about personal health status.
Reports being 'constantly terrified.' Any new body sensation triggers immediate alarm and medical research. Negative results provide only 2-3 days of relief. MET.
Criterion D: The individual performs excessive health-related behaviors or exhibits maladaptive avoidance.
Excessive health behaviors: daily self-examinations, 2-3 hours online research, 4 MRIs, 12 blood panels, 2 colonoscopies, multiple specialist visits in 4 years. MET — care-seeking type.
Criterion E: ≥6 months, though specific illness feared may change.
Four-year duration. Initially feared pancreatic cancer (after coworker's diagnosis), then shifted to brain tumor, then melanoma, cycling through various cancers. MET.
Criterion F: Not better explained by another mental disorder.
Worry is specifically about health/illness. Does not extend to multiple domains (excludes GAD). Not focused on body appearance (excludes BDD). Not a specific feared stimulus (excludes specific phobia). MET.
Step 2: Differentiating from Somatic Symptom Disorder
The critical distinction between IAD and SSD is the role of somatic symptoms:
| Feature | Illness Anxiety Disorder | Somatic Symptom Disorder | This Patient |
|---|---|---|---|
| Somatic symptoms | Absent or mild | One or more distressing symptoms | IAD: minimal symptoms (occasional headache, fatigue) |
| Primary concern | Anxiety about having illness | Distress about somatic symptoms | IAD: fear of cancer, not distress about physical sensations |
| Self-monitoring | Checking for signs of disease | Focused on the symptoms themselves | IAD: body checking for lumps, moles |
| Medical utilization | Extensive investigation seeking | Extensive medical visits for symptom relief | IAD: 4 MRIs, 12 blood panels, 2 colonoscopies |
| Reassurance response | Brief relief from negative results | Symptoms persist despite normal results | IAD: 2-3 days relief, then anxiety returns |
Diagnostic Distinction
The absence of prominent somatic symptoms is the key differentiator. Mr. G's distress centers on the FEAR of illness, not on somatic experiences. His body 'feels mostly fine,' but the cognitive preoccupation with undetected disease drives his behavior. This is IAD, not SSD.
Diagnostic Formulation
Diagnostic Conclusion
Illness Anxiety Disorder, Care-Seeking Type (F45.21): All 6 DSM-5-TR criteria met. Four-year health preoccupation with minimal somatic symptoms. Care-seeking type (extensive medical utilization rather than care avoidance). SSD excluded by absence of prominent somatic symptoms. Treatment: CBT targeting health anxiety cognitions (catastrophic misinterpretation, intolerance of uncertainty, reassurance-seeking behavior), response prevention (limiting body checks and online research), and SSRI if CBT alone is insufficient.
Teaching Points
- IAD replaced DSM-IV 'Hypochondriasis' in DSM-5-TR. The DSM-IV category was split: patients with prominent somatic symptoms are now diagnosed with Somatic Symptom Disorder; patients with minimal somatic symptoms but high health anxiety receive IAD.
- IAD has two subtypes: care-seeking (frequent medical visits, testing) and care-avoidant (avoids medical care due to fear of receiving a diagnosis). Mr. G exemplifies the care-seeking type. The care-avoidant type may be harder to identify because these patients are NOT in the medical system.
- Reassurance-seeking is a core maintaining behavior in IAD. Negative medical results provide temporary relief but do not resolve the underlying anxiety. The brief 'reassurance window' (days to weeks) reinforces the cycle by teaching the patient that relief requires medical investigation.
- CBT for IAD includes cognitive restructuring (challenging probability overestimation of rare diseases, addressing intolerance of bodily uncertainty), behavioral experiments (delaying medical checks to test catastrophic predictions), and response prevention (limiting body checking and online research).
- Clinicians should avoid both extremes: dismissing the patient's concerns ('It's all in your head') and providing excessive reassurance (ordering unnecessary tests). A validating but firm approach that acknowledges the anxiety while declining unnecessary investigations is the recommended clinical stance.