A 25-year-old male was injured during an earthquake. A social worker reports that he was later found in another town, and the man has no memory of how he got there or of his personal identity. What is the most likely diagnosis?

Correct Answer: C. Dissociative fugue

Dissociative fugue is characterized by sudden, unexpected travel away from home or workplace with inability to recall one's past identity and personal information. The key discriminating features in this case are: (1) sudden onset following acute trauma (earthquake), (2) purposeful travel to a distant location (found in another town), (3) complete amnesia for personal identity and how he got there, and (4) assumption of a new identity or confused wandering. Unlike acute stress disorder (which presents with hyperarousal, re-experiencing, and avoidance within minutes to days), fugue involves actual physical relocation with dissociative amnesia. The patient's inability to remember his identity or the journey itself—not just traumatic memories—is pathognomonic for fugue. In Indian psychiatric practice, fugue states are often triggered by severe psychosocial stressors (natural disasters, communal violence, family trauma) and typically last hours to days, occasionally weeks. The social worker's observation of the patient being found in a different location with no memory of transit is the critical clinical clue that distinguishes fugue from other dissociative or trauma-related disorders. Recovery is usually spontaneous and complete once the fugue state resolves.

Why the other options are wrong

A. Acute stress disorder — ASD presents with hyperarousal, intrusive memories, avoidance, and negative mood within 3 days to 1 month of trauma. It does NOT involve purposeful travel, loss of personal identity, or amnesia for how one reached a distant location. ASD patients remain in their familiar environment and are aware of their identity; they suffer from re-experiencing the trauma, not fugue-like wandering. B. Dissociative identity disorder — DID involves multiple distinct personality states with separate identities, memories, and behaviors that recurrently take control. This patient shows no evidence of switching between personalities or multiple identities—only amnesia for his own identity and travel. DID typically develops over years from childhood trauma, not acutely after a single disaster. D. PTSD — PTSD develops after 1 month of trauma exposure and is characterized by re-experiencing, avoidance, negative cognitions, and hyperarousal—not by sudden travel with complete amnesia for identity. While this patient may later develop PTSD, the acute presentation of fugue (purposeful relocation + identity amnesia) is the primary diagnosis at this moment.

High-Yield Facts

Mnemonics

FUGUE = Flight + Unaware + Gone + Unidentified + Ends Flight away from home, Unaware of identity, Gone to distant place, Unidentified how they got there, Ends spontaneously. Use this when you see 'found in another town with no memory of identity or travel.' Fugue vs ASD: LOCATION Fugue = patient LEAVES home; ASD = patient STAYS home (hyperaroused in place). If the question says 'found in another town,' think fugue.

NBE Trap

NBE pairs earthquake trauma with dissociative symptoms and expects students to default to PTSD or ASD (the 'obvious' trauma diagnoses). The trap is missing the specific feature of purposeful travel + identity amnesia, which is pathognomonic for fugue, not the more common post-trauma disorders.

Clinical Pearl

In Indian emergency departments, fugue states are often misdiagnosed as PTSD or acute confusion because clinicians focus on the trauma history rather than the specific triad of travel + identity loss + amnesia for transit. A simple bedside question—"Do you know who you are? How did you get here?"—rapidly distinguishes fugue (both answers 'no') from ASD/PTSD (identity preserved, trauma memories intrusive).

_Reference: Kaplan & Sadock's Synopsis of Psychiatry (dissociative disorders section); DSM-5 criteria for Dissociative Fugue; Harrison's Principles of Internal Medicine Ch. 387 (Psychiatric Disorders)_