Step 1: Understanding the Question:
A man is convinced that his nose is too long, even though his friends and, by implication, three separate plastic surgeons do not find anything wrong with it. He has gone from surgeon to surgeon looking for correction, and each one has turned him down. We need the condition that fits this fixed, false belief about his own body.
Step 2: Key Concept:
Hypochondriasis is fear of having a serious underlying disease based on misreading normal body sensations, not a fixed belief about one's physical appearance.
Somatisation is repeated physical complaints in many body systems, without an organic cause, used to seek medical attention.
Munchausen syndrome is fabricating or inducing symptoms on purpose to play the sick role and gain attention.
Delusional disorder, somatic type, is a fixed, false belief about the body that will not budge even with clear evidence against it. This form has also been called monosymptomatic hypochondriacal psychosis in older texts.
Step 3: Detailed Explanation:
This man's belief about his nose is not backed by any objective defect, since his friends see nothing wrong and three independent plastic surgeons, who would have every professional reason to operate if a real deformity existed, all refused. Despite this consistent, repeated reassurance, he keeps chasing surgery. That refusal to accept solid outside evidence is what makes the belief delusional rather than an ordinary worry.
It is not hypochondriasis, because he is not worried about a hidden disease, he is fixed on how his body looks.
It is not somatisation, because there are no multiple unexplained physical symptoms across body systems here, only one fixed idea about the nose.
It is not Munchausen syndrome, because he is not faking a disease to get attention or play a sick role, he genuinely believes his nose has a physical flaw.
Note: in current classification, a milder version of this pattern with some retained insight is called body dysmorphic disorder, but when the belief is completely fixed and does not bend to repeated, consistent contrary evidence from multiple experts, as written here, it carries delusional intensity and is placed under delusional disorder, somatic type.
Step 4: Final Answer:
A fixed, unshakeable false belief about a body part, undisturbed by consistent reassurance from multiple specialists, is delusional disorder.