Obsessive-Compulsive and Related Disorders Practice Questions

Q: The content of thought in olfactory reference syndrome is:

Foul odour. **Explanation:** **Olfactory Reference Syndrome (ORS)** is a psychiatric condition characterized by the persistent, false belief that one emits a foul or offensive body odor (e.g., breath, sweat, or flatulence) which is noticeable to others. This leads to significant distress, social anxiety, and repetitive behaviors like excessive showering or constant checking for odors. **Why the correct answer is right:** * **D. Foul odour:** The core psychopathology of ORS is the preoccupation with a **malodorous smell**. Patients misinterpret the neutral actions of others (like opening a window or sneezing) as reactions to their perceived smell. In modern classification (ICD-11), it is categorized under "Obsessive-Compulsive or Related Disorders." **Why the incorrect options are wrong:** * **A. Erotic:** Erotic themes are characteristic of **Erotomania (de Clerambault’s syndrome)**, where the patient believes a person of higher status is in love with them. * **B. Infidelity:** This is the hallmark of **Delusional Jealousy (Othello Syndrome)**, where the patient is convinced their partner is being unfaithful without evidence. * **C. Love:** Similar to erotic themes, delusions of love are associated with Erotomania rather than sensory-based reference syndromes. **High-Yield Clinical Pearls for NEET-PG:** * **Insight:** Insight in ORS can range from poor to absent (delusional). * **Social Isolation:** Patients often become "housebound" due to the shame of their perceived odor. * **Differential Diagnosis:** Must be distinguished from **Monosymptomatic Hypochondriacal Psychosis** and temporal lobe epilepsy (where olfactory hallucinations are brief and paroxysmal). * **Treatment:** Managed with SSRIs (for OCD-like symptoms) and low-dose atypical antipsychotics.

Q: A college student is brought to the student health center by his roommate. He has been missing class because he needs to check the room lock many times before he can leave. Once he starts to ride his bicycle to class, he frequently returns several times to lock the door. He repeats this ritual every morning and often when he leaves the house. He misses his appointments and his academic performance suffers. His hands are chafed. Which of the following is the most likely diagnosis?

Obsessive compulsive disorder. **Explanation:** The clinical presentation is a classic case of **Obsessive-Compulsive Disorder (OCD)**. The patient experiences recurrent, intrusive thoughts (obsessions) regarding security/safety, which lead to repetitive behaviors (compulsions) like checking the lock. These rituals are time-consuming, cause significant functional impairment (missing classes/appointments), and are ego-dystonic. The mention of "chafed hands" is a high-yield clinical sign suggesting excessive hand-washing, another common compulsion. **Why other options are incorrect:** * **Generalized Anxiety Disorder (GAD):** Characterized by excessive, uncontrollable worry about various everyday issues (finances, health, work) for at least 6 months, rather than specific ritualistic behaviors or obsessions. * **Panic Disorder:** Involves recurrent, unexpected panic attacks (sudden surges of intense fear with physical symptoms like palpitations and dyspnea) and the fear of future attacks. * **Paranoid Personality Disorder:** A pervasive pattern of distrust and suspiciousness where others' motives are interpreted as malevolent. It does not involve ritualistic compulsions. **Clinical Pearls for NEET-PG:** * **Ego-dystonic:** In OCD, the patient recognizes that the symptoms are irrational and a product of their own mind (unlike OCPD, which is ego-syntonic). * **First-line Treatment:** Cognitive Behavioral Therapy (CBT) with **Exposure and Response Prevention (ERP)** and/or **SSRIs** (often requiring higher doses than in depression). * **Neurobiology:** Associated with structural/functional abnormalities in the **Orbitofrontal cortex, Anterior Cingulate Cortex, and Caudate nucleus** (Cortico-striato-thalamo-cortical circuit).

Q: What is the most common psychiatric disorder seen with PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections)?

Obsessive-Compulsive Disorder (OCD). **Explanation:** **PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections)** is a clinical diagnosis characterized by the sudden, "overnight" onset of neuropsychiatric symptoms following a Group A Beta-hemolytic Streptococcal (GABHS) infection. **Why Obsessive-Compulsive Disorder (OCD) is correct:** The hallmark of PANDAS is the abrupt onset of **Obsessive-Compulsive Disorder (OCD)** or **Tic disorders**. The underlying pathophysiology involves **molecular mimicry**, where antibodies produced against streptococcal bacteria cross-react with the **basal ganglia** (specifically the caudate nucleus). Since the basal ganglia are integral to the cortico-striato-thalamo-cortical (CSTC) circuits that regulate behavior and motor control, their dysfunction manifests primarily as acute OCD. **Why other options are incorrect:** * **Anxiety Disorder:** While separation anxiety is a common *co-occurring* symptom in PANDAS, it is not the defining or most common primary diagnosis compared to OCD. * **Depression:** Mood lability and irritability are frequently seen, but clinical depression is not the primary diagnostic feature of the syndrome. * **Delusional Disorder:** Psychotic symptoms are rare in PANDAS; the presentation is typically neurodevelopmental and behavioral rather than psychotic. **High-Yield Clinical Pearls for NEET-PG:** * **Diagnostic Criteria:** Sudden onset of OCD/Tics, prepubertal onset (usually ages 3–12), and temporal association with GABHS (confirmed by positive throat culture or elevated ASO/Anti-DNase B titers). * **Associated Symptoms:** "Sun-setting" of symptoms, urinary urgency, hyperactivity (ADHD-like), and deterioration in handwriting (dysgraphia). * **Treatment:** Standard OCD management (SSRIs, CBT) and, in severe cases, immunomodulatory therapies (IVIG or plasmapheresis). Antibiotics are used to treat the active infection.

Q: In a child with obsessive-compulsive disorder (OCD), MRI will reveal reduced volume (atrophy) of which of the following structures?

Caudate nucleus. **Explanation:** The pathophysiology of Obsessive-Compulsive Disorder (OCD) is primarily linked to the **Cortico-Striato-Thalamo-Cortical (CSTC) circuit**. This circuit involves the orbitofrontal cortex, the anterior cingulate cortex, and the basal ganglia. **Why Caudate Nucleus is correct:** The **Caudate Nucleus** is a key component of the striatum within the CSTC circuit. In patients with OCD, there is a failure of the caudate nucleus to properly "gate" or filter intrusive thoughts and impulses. Structural neuroimaging (MRI) studies in both children and adults with OCD have consistently demonstrated **reduced volume (atrophy)** of the caudate nucleus. Functional imaging (PET/fMRI) often shows compensatory hyperactivity in this same region. **Analysis of Incorrect Options:** * **Putamen & Globus Pallidus:** While these are parts of the basal ganglia, they are not the primary sites of structural atrophy identified in classic OCD neuroimaging studies. The pathology is more specific to the "executive" loop involving the caudate. * **Cerebellum:** While the cerebellum is increasingly studied in various psychiatric conditions, it is not the hallmark site of atrophy for OCD. **High-Yield NEET-PG Pearls:** * **Neurobiology:** OCD is associated with **serotonin dysregulation** (hence SSRIs are first-line). * **PANDAS:** Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections can cause sudden-onset OCD in children due to autoimmune inflammation of the **basal ganglia**. * **Treatment:** The most effective psychological treatment is **Exposure and Response Prevention (ERP)**, a form of CBT. * **Surgical Target:** In refractory OCD, deep brain stimulation (DBS) or cingulotomy targets components of the CSTC circuit.

Q: A 21-year-old girl is disturbed by the appearance of her nose, which she believes is disfiguring, although others do not perceive it that way. What is the likely diagnosis?

Body dysmorphic disorder. ### Explanation **Correct Answer: C. Body dysmorphic disorder (BDD)** **Why it is correct:** Body Dysmorphic Disorder is characterized by a distressing or impairing preoccupation with one or more **perceived defects or flaws** in physical appearance that are **not observable or appear slight** to others. In this case, the patient’s belief that her nose is "disfiguring" despite others perceiving it as normal is the classic presentation. Patients often perform repetitive behaviors (mirror checking, excessive grooming) or mental acts in response to these concerns. **Why the other options are incorrect:** * **A. Delusional Disorder (Somatic type):** While BDD can occur with absent insight (delusional intensity), BDD is the more specific diagnosis for appearance-related concerns. In BDD, the focus is specifically on "defect in appearance," whereas somatic delusions usually involve bodily functions or sensations (e.g., infestation, foul odor). * **B. Obsessive Compulsive Disorder (OCD):** While BDD is categorized under "OCD and Related Disorders" in DSM-5 due to repetitive behaviors, the specific focus on physical appearance makes BDD the most accurate diagnosis. * **D. Specific Phobia:** This involves an irrational fear of a specific object or situation (e.g., heights, spiders). It does not involve distorted self-perception or preoccupation with physical flaws. **High-Yield Clinical Pearls for NEET-PG:** * **Common Site:** The nose is the most common feature of concern (Rhinoplasty seekers). * **Gender:** It is equally common in males and females, though females are more likely to have comorbid eating disorders. * **Treatment of Choice:** **SSRIs** (often requiring higher doses than in depression) and **Cognitive Behavioral Therapy (CBT)**. * **Key Distinction:** Patients with BDD often seek cosmetic surgery or dermatological treatments, which rarely resolve the underlying psychological distress.

Q: Which neurotransmitters are primarily involved in Obsessive-Compulsive Disorder (OCD)?

Serotonin. **Explanation:** **1. Why Serotonin is Correct:** The **Serotonin Hypothesis** is the most widely accepted neurochemical theory for OCD. It is based on the clinical observation that **Selective Serotonin Reuptake Inhibitors (SSRIs)** and Clomipramine (a serotonergic TCA) are highly effective in reducing obsessive-compulsive symptoms. Research indicates a dysregulation in the serotonergic system, particularly involving the 5-HT receptors, which modulates the **Cortico-Striato-Thalamo-Cortical (CSTC) circuit**—the primary neuroanatomical pathway implicated in OCD. **2. Why Other Options are Incorrect:** * **GABA:** This is the primary inhibitory neurotransmitter. While it plays a significant role in **Generalized Anxiety Disorder (GAD)** and panic disorders, it is not the primary driver of OCD pathology. * **Norepinephrine:** This neurotransmitter is central to the "fight or flight" response and is primarily involved in **Panic Disorder** and **Depression**. Drugs that purely increase norepinephrine (like Desipramine) are generally ineffective in treating OCD. * **Dopamine:** While dopamine dysregulation in the basal ganglia is linked to OCD (especially in patients with comorbid Tic disorders), it is considered a **secondary** modulator rather than the primary neurotransmitter. **3. NEET-PG High-Yield Clinical Pearls:** * **Drug of Choice (DOC):** SSRIs (e.g., Fluoxetine, Fluvoxamine, Sertraline). * **Most Potent Drug:** **Clomipramine** (though not first-line due to side effects). * **Treatment Note:** OCD requires **higher doses** of SSRIs and a **longer duration** (10–12 weeks) to show a response compared to depression. * **Neuroanatomy:** The **Orbitofrontal Cortex (OFC)** and the **Anterior Cingulate Cortex** are the specific areas of the CSTC circuit most associated with OCD symptoms.

Q: Which of the following is NOT true about trichobezoars?

It is caused by Trichuris.. ### Explanation **1. Why Option A is the Correct Answer (The "False" Statement):** The term **Trichobezoar** is derived from the Greek word *thrix* (hair). It is a physical mass of accumulated hair in the gastrointestinal tract, not an infection. **Trichuris trichiura** (Whipworm), on the other hand, is a soil-transmitted helminth (parasite) that causes trichuriasis. There is no causal link between the parasite *Trichuris* and the formation of a hairball. **2. Analysis of Incorrect Options (True Statements):** * **Option B:** It is indeed a psychiatric manifestation. It is most commonly associated with **Trichotillomania** (impulse-control disorder involving hair pulling) and **Trichophagia** (compulsive eating of hair). * **Option C:** By definition, a bezoar is a solid mass of indigestible material. A trichobezoar specifically refers to a **ball of hair** typically found in the stomach, as hair cannot be digested or moved effectively by peristalsis. * **Option D:** The clinical history usually involves chronic **hair pulling** (trichotillomania) followed by **hair sucking or swallowing** (trichophagia). Over time, this leads to the accumulation of the bezoar. **3. Clinical Pearls for NEET-PG:** * **Rapunzel Syndrome:** An extreme form of trichobezoar where the "tail" of the hairball extends from the stomach into the small intestine (jejunum/ileum). * **Demographics:** Most commonly seen in adolescent females with underlying psychiatric comorbidities (Anxiety, OCD, or Depression). * **Clinical Presentation:** Often presents with epigastric pain, nausea, vomiting, early satiety, and a palpable abdominal mass. * **Diagnosis:** Gold standard is **Upper GI Endoscopy**; CT scan shows a characteristic mottled gas pattern within the mass.

Q: Domestic squalor is related to which of the following disorders?

Hoarding disorder. ### Explanation **Correct Option: C. Hoarding disorder** **Domestic squalor** refers to a state of extreme filth, clutter, and neglect in a person's living environment. It is a hallmark complication of **Hoarding Disorder**. In this condition, patients have persistent difficulty discarding or parting with possessions, regardless of their actual value. This leads to an accumulation of items that congest and clutter active living areas, compromising their intended use. When the accumulation includes organic waste or trash, it results in domestic squalor, which poses significant health and fire risks. **Why other options are incorrect:** * **A. Somatoform disorder:** These patients present with physical symptoms that suggest a medical condition but are not fully explained by one. It does not typically involve environmental neglect or clutter. * **B. Body dysmorphic disorder (BDD):** Characterized by a preoccupation with perceived defects in physical appearance. While related to OCD, its focus is on self-image, not the accumulation of objects. * **D. Olfactory reference syndrome:** A condition where an individual falsely believes they emit a foul or offensive body odor. This leads to excessive grooming or social withdrawal, not domestic squalor. **High-Yield Clinical Pearls for NEET-PG:** * **Diogenes Syndrome:** A specific geriatric syndrome characterized by extreme self-neglect, domestic squalor, social withdrawal, and hoarding. It is often associated with dementia or personality disorders. * **Treatment of Hoarding:** It is notoriously difficult to treat. **Cognitive Behavioral Therapy (CBT)** tailored for hoarding is the first-line psychological treatment, often combined with **SSRIs**. * **DSM-5 Classification:** Hoarding Disorder is now a distinct diagnosis under the "Obsessive-Compulsive and Related Disorders" category, rather than just a symptom of OCD.

Question 1

The content of thought in olfactory reference syndrome is:

Accepted Answer

Foul odour

Answer

Erotic

Answer

Infidelity

Answer

Love

Question 2

A college student is brought to the student health center by his roommate. He has been missing class because he needs to check the room lock many times before he can leave. Once he starts to ride his bicycle to class, he frequently returns several times to lock the door. He repeats this ritual every morning and often when he leaves the house. He misses his appointments and his academic performance suffers. His hands are chafed. Which of the following is the most likely diagnosis?

Accepted Answer

Obsessive compulsive disorder

Answer

Generalized anxiety disorder

Answer

Panic disorder

Answer

Paranoid personality disorder

Question 3

What is the most common psychiatric disorder seen with PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections)?

Accepted Answer

Obsessive-Compulsive Disorder (OCD)

Answer

Depression

Answer

Anxiety disorder

Answer

Delusional disorder

Question 4

In a child with obsessive-compulsive disorder (OCD), MRI will reveal reduced volume (atrophy) of which of the following structures?

Accepted Answer

Caudate nucleus

Answer

Putamen

Answer

Globus pallidus

Answer

Cerebellum

Question 5

A person washes hands repeatedly due to a fear of contracting HIV. What condition is this person likely suffering from?

Accepted Answer

Obsessive-compulsive disorder

Answer

Phobic disorder

Answer

Dissociative and conversion disorder

Answer

Somatoform disorder

Question 6

All are treatment modalities of Obsessive-Compulsive Disorder except?

Accepted Answer

MAO inhibitors

Answer

Exposure and response prevention

Answer

Psychoanalytic psychotherapy

Answer

Clomipramine

Question 7

A 21-year-old girl is disturbed by the appearance of her nose, which she believes is disfiguring, although others do not perceive it that way. What is the likely diagnosis?

Accepted Answer

Body dysmorphic disorder

Answer

Delusional disorder

Answer

Obsessive compulsive disorder

Answer

Specific phobia

Question 8

Which neurotransmitters are primarily involved in Obsessive-Compulsive Disorder (OCD)?

Accepted Answer

Serotonin

Answer

GABA

Answer

Norepinephrine

Answer

Dopamine

Question 9

Which of the following is NOT true about trichobezoars?

Accepted Answer

It is caused by Trichuris.

Answer

It is a psychiatric manifestation.

Answer

It is a ball of hair found in the stomach.

Answer

Hair pulling and hair sucking are usually seen.

Question 10

Domestic squalor is related to which of the following disorders?

Accepted Answer

Hoarding disorder

Answer

Somatoform disorder

Answer

Body dysmorphic disorder

Answer

Olfactory reference syndrome

Obsessive-Compulsive and Related Disorders — MCQs

Obsessive-Compulsive and Related Disorders — MCQs

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