A 21 year old medical student and his batchmate and girlfriend came to psychiatry outpatient for evaluation. The girlfriend of the patient, said that he is very boring and its getting difficult for her to continue in the relationship. She repoed that ‘He is way too serious about studies ‘. He goes to every single clinical posting and also asks the postgraduates to take attendance. After the college, he routinely goes to library, where he stays till late night and has staed reading Harrison’s medicine. A couple of days back he got into argument with a pharmacology professor about drug of choice of a paicular disorder and argued with the professor in front of entire batch. The patient on the other hand repoed, I don’t understand why is she upset with me. I am doing the right thing and i don’t understand why other students, teachers and principal cannot be as dedicated as me. What is the diagnosis?

**Core Concept**
The patient's behavior is characterized by an excessive preoccupation with academic and professional matters, social isolation, and an inability to understand how his actions are perceived by others. This presentation is suggestive of an obsessive-compulsive personality disorder, a type of personality disorder that is marked by a pervasive pattern of preoccupation with orderliness, perfectionism, and mental and interpersonal control.

**Why the Correct Answer is Right**
The patient's behavior is indicative of an obsessive-compulsive personality disorder, as he exhibits a rigid adherence to rules and expectations, a lack of flexibility, and an excessive preoccupation with details. His behavior is also characterized by an inability to relax and enjoy leisure activities, as evident from his routine of staying in the library till late night. His argument with the pharmacology professor and his insistence on taking attendance also suggest a rigid and perfectionistic attitude. The patient's inability to understand why his girlfriend is upset with him is also a hallmark of this disorder, as individuals with obsessive-compulsive personality disorder often have difficulty empathizing with others and understanding their perspectives.

**Why Each Wrong Option is Incorrect**
**Option A:** This option might be tempting, but it is incorrect because the patient's behavior is not primarily driven by anxiety or fear, which are the hallmark symptoms of anxiety disorders. While the patient may exhibit some anxious behavior, such as arguing with the professor, his overall behavior is more characteristic of a personality disorder.

**Option B:** This option is incorrect because the patient's behavior is not primarily driven by a lack of motivation or interest in social relationships. While the patient may be socially isolated, his behavior is more characteristic of a rigid and perfectionistic attitude, which is a hallmark of obsessive-compulsive personality disorder.

**Option C:** This option is incorrect because the patient's behavior is not primarily driven by a lack of impulse control or aggression. While the patient may exhibit some aggressive behavior, such as arguing with the professor, his overall behavior is more characteristic of a rigid and perfectionistic attitude, which is a hallmark of obsessive-compulsive personality disorder.

**Option D:** This option is incorrect because the patient's behavior is not primarily driven by a lack of emotional regulation or mood instability. While the patient may exhibit some emotional dysregulation, such as becoming upset with his girlfriend, his overall behavior is more characteristic of a rigid and perfectionistic attitude, which is a hallmark of obsessive-compulsive personality disorder.

**Clinical Pearl / High-Yield Fact**
Individuals with obsessive-compulsive personality disorder often have difficulty forming and maintaining relationships, as their rigid and perfectionistic attitudes can be off-putting to others. They may also have difficulty with intimacy and emotional expression, as they may view emotional expression as a sign of weakness or lack of control.

**Correct Answer: C. Obsessive-Compulsive Personality Disorder**

✓ Correct Answer: B. Anankastic personality disorder