An undertrial prisoner repeatedly gives absurdly approximate answers: he writes '2 plus 2 equals 5' and says a week has ten days, yet answers simple everyday questions correctly when distracted. He shows no other psychotic features. The most likely diagnosis is:

• A Malingering
• B Schizophrenia, disorganised type
• C Ganser syndrome ✓
• D Dementia

Explanation

Ganser syndrome is a dissociative disorder characterised by approximate answers, seen classically in prisoners awaiting trial, often called prison psychosis. The hallmark is answers that are near misses rather than random errors, with intact function elsewhere, suggesting unconscious production rather than deliberate fabrication. It kills the malingering distractor because the answers cluster close to correct values, a pattern malingerers rarely produce so consistently and unconsciously.

Reference: Gelder's Shorter Oxford Textbook of Psychiatry, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.