Lalu prasad 45 yrs old male presents to OPD with complaining about the continuous non-progresive headache from last 7 days. He believes that he has a brain tumor. for that, there is he consulting many neurologists in past even all of the investigation have been within normal limits. The patient requested for other investigation to reveal that he has a brain tumor. The psychiatric evaluation shows the disease on the background of a normal investigation. The most probable diagnosis is –

**Core Concept**
The patient's presentation of persistent, non-progressive headaches despite normal investigations, along with a belief in having a brain tumor, suggests a psychiatric disorder rather than a neurological one. This condition is characterized by a preoccupation with having a serious medical condition, despite medical reassurance and the absence of any underlying pathology.

**Why the Correct Answer is Right**
The patient's symptoms and behaviors are indicative of **Illness Anxiety Disorder (IAD)**, formerly known as Hypochondriasis. This disorder is marked by excessive worry about having a serious illness, despite medical reassurance and a lack of evidence to support these fears. In IAD, the individual's anxiety and fear are disproportionate to the actual risk of illness. The patient's repeated consultations with neurologists and requests for further investigations are attempts to alleviate their anxiety and confirm their feared diagnosis.

**Why Each Wrong Option is Incorrect**
* **Option A:** This is incorrect because the patient's symptoms do not meet the diagnostic criteria for Conversion Disorder (also known as Functional Neurological Disorder). Conversion Disorder is characterized by symptoms that affect voluntary motor or sensory function, such as paralysis or numbness, without a clear medical explanation. The patient's headache, while persistent, is not a focal symptom that would suggest Conversion Disorder.
* **Option B:** This is incorrect because the patient's symptoms do not meet the diagnostic criteria for Somatization Disorder (now known as Somatic Symptom Disorder). Somatization Disorder is characterized by multiple, recurring physical complaints that are not explainable by a medical condition, but the patient's primary concern is a specific diagnosis of a serious medical condition (in this case, a brain tumor).
* **Option C:** This is incorrect because the patient's symptoms do not meet the diagnostic criteria for Factitious Disorder. Factitious Disorder is characterized by the intentional production or feigning of physical or psychological symptoms, usually to assume the sick role. While the patient is seeking medical attention, there is no evidence to suggest that they are intentionally producing or feigning symptoms.

**Clinical Pearl / High-Yield Fact**
Key features of Illness Anxiety Disorder include excessive worry about having a serious illness, despite medical reassurance and a lack of evidence to support these fears. The patient's anxiety and fear are disproportionate to the actual risk of illness, and they may exhibit behaviors such as repeated medical consultations and requests for further investigations to alleviate their anxiety.

**Correct Answer: D.**

✓ Correct Answer: A. Hypochondriasis