DHA / DOH / MOH exam (UAE) psychiatry & dermatology questions

DSM-5 requires at least five of nine criterion symptoms (depressed mood, anhedonia, sleep change, appetite/weight change, psychomotor change, fatigue, worthlessness/guilt, concentration difficulty, suicidal ideation) present for a minimum of 2 weeks, representing a change from previous functioning, with at least one symptom being depressed mood or anhedonia. This patient meets five symptoms (mood, anhedonia, insomnia, appetite/weight loss, fatigue, concentration) over 5 weeks, satisfying the duration and symptom count threshold for a major depressive episode. The diagnosis also requires ruling out substance use, another medical condition, and that the episode is not better explained by a psychotic or bipolar disorder.

• A. Four days of elevated mood describes hypomania, not a depressive episode.
• B. Six months is not the DSM-5 threshold; 2 weeks is required, and social withdrawal alone is not a criterion symptom.
• D. This describes seasonal affective pattern, not the core duration/symptom criteria being tested.

Selective serotonin reuptake inhibitors are recommended as first-line pharmacotherapy for moderate-to-severe depression by major guidelines (NICE, APA) because of their comparable efficacy to older agents with a more favorable tolerability and safety profile, including lower toxicity in overdose. Tricyclics and MAOIs are reserved for treatment-resistant cases due to greater anticholinergic, cardiac, and dietary/interaction burdens. Benzodiazepines have no role as antidepressants and carry dependence risk. Treatment response should be reviewed after 2-4 weeks, with an adequate trial lasting 6-8 weeks before considering a switch.

• B. Tricyclics are effective but have greater cardiotoxicity in overdose and more anticholinergic side effects, making them second-line.
• C. MAOIs require dietary restrictions and are reserved for refractory depression due to interaction risks.
• D. Benzodiazepines treat anxiety symptoms, not the core depressive illness, and risk dependence.

Citalopram (and its enantiomer escitalopram to a lesser degree) carries a well-documented dose-dependent risk of QT interval prolongation and torsades de pointes, prompting regulatory warnings against high doses and against use in patients with pre-existing QT prolongation or significant cardiac disease. Sertraline is generally considered the preferred SSRI in patients with cardiovascular disease because of its more favorable cardiac safety profile and extensive post-myocardial infarction trial data (SADHART study). In a patient with borderline QTc and prior myocardial infarction, selecting an agent with lower arrhythmic risk is the safer approach. Baseline and follow-up ECG monitoring is prudent when QT-prolonging agents cannot be avoided.

• A. Fluoxetine has a lower reported risk of QT prolongation compared with citalopram.
• B. Sertraline has the most favorable cardiac safety data among SSRIs and is often preferred post-myocardial infarction.
• C. Escitalopram carries some QT risk at high doses but less than citalopram and is not the agent most strongly implicated.

Serotonin syndrome results from excess serotonergic activity, classically triggered by combining an SSRI with another serotonergic agent such as tramadol, which inhibits serotonin reuptake in addition to its opioid effects. The clinical triad of autonomic instability (fever, tachycardia, hypertension, diaphoresis), neuromuscular abnormalities (hyperreflexia, clonus, tremor), and altered mental status (agitation) distinguishes it, with clonus and hyperreflexia being more prominent than the lead-pipe rigidity and bradyreflexia seen in neuroleptic malignant syndrome. Management includes stopping serotonergic agents, supportive cooling, benzodiazepines for agitation, and cyproheptadine for moderate-to-severe cases. Neuroleptic malignant syndrome typically develops over days with antipsychotic exposure and shows rigidity rather than clonus.

• B. Neuroleptic malignant syndrome is associated with antipsychotics and presents with lead-pipe rigidity and bradyreflexia, not hyperreflexia and clonus.
• C. Malignant hyperthermia occurs with volatile anesthetics or succinylcholine in susceptible individuals, not SSRI-tramadol combinations.
• D. Anticholinergic toxicity causes dry skin and absent bowel sounds rather than diaphoresis and hyperreflexia with clonus.

Abrupt cessation of an SSRI, particularly one with a short half-life such as paroxetine, commonly produces a discontinuation syndrome within days, characterized by dizziness, paresthesias or 'electric shock' sensations, nausea, irritability, and sleep disturbance with vivid dreams. This occurs due to rapid downregulation changes in serotonergic receptors that have adapted to chronic reuptake inhibition, and it typically resolves within 1-3 weeks. Management involves reassurance, restarting the SSRI if symptoms are severe, or tapering gradually; fluoxetine's longer half-life makes it less prone to this reaction. Relapse of depression develops more gradually over weeks and is characterized by mood and cognitive symptoms rather than the sensory and somatic symptoms seen here.

• A. Serotonin syndrome results from excess serotonergic activity from combining agents, not from stopping a single serotonergic drug.
• B. Relapse typically evolves over weeks with return of depressive mood symptoms, not an abrupt sensory/somatic cluster within days of stopping the drug.
• C. Generalized anxiety disorder requires chronic excessive worry over at least 6 months, not an acute reaction temporally linked to drug cessation.

Valproate is a known teratogen associated with neural tube defects, congenital malformations, and long-term neurodevelopmental impairment including lower IQ and autism spectrum disorder risk in children exposed in utero. Current guidelines (including MHRA and FDA pregnancy prevention program requirements) mandate that women of childbearing potential use highly effective contraception for the entire duration of valproate therapy. Valproate should only be prescribed to women of childbearing age if other treatments are ineffective or not tolerated, and the risks must be documented as discussed. Folic acid supplementation does not eliminate the teratogenic risk and does not substitute for contraception.

• A. Contraception is required for the entire duration of treatment, not only when pregnancy is planned within a specific timeframe.
• C. Valproate carries a high risk of major malformations and neurodevelopmental impairment and is not safe in pregnancy.
• D. Folic acid reduces but does not eliminate neural tube defect risk, and pregnancy should be avoided, not attempted, while on valproate.

This patient meets criteria for generalized anxiety disorder: excessive, difficult-to-control worry about multiple life domains for at least 6 months, accompanied by physical symptoms such as muscle tension and restlessness, with secondary causes excluded by normal thyroid function. First-line treatment per current guidelines (NICE, APA) is an SSRI (such as sertraline or escitalopram) combined with cognitive behavioral therapy, which addresses both the physiological and cognitive components of the disorder. Benzodiazepines are not first-line due to dependence risk and are reserved for short-term crisis use. Beta-blockers target somatic symptoms only and do not address the underlying disorder.

• A. Antipsychotics are not first-line for GAD and are reserved for treatment-resistant cases under specialist guidance.
• C. Propranolol only addresses peripheral autonomic symptoms and is not a primary treatment for GAD.
• D. Benzodiazepines are not first-line therapy for GAD due to dependence and withdrawal risk with long-term use.

Benzodiazepines are recommended only for short-term use (typically a few weeks) in anxiety disorders due to the risk of tolerance, dependence, and withdrawal symptoms, as demonstrated by this patient's dose escalation and rebound symptoms on missed doses. The appropriate long-term strategy is a gradual, supervised taper of the benzodiazepine combined with initiation of an SSRI and cognitive behavioral therapy, which are first-line, non-habit-forming treatments for sustained anxiety control. Abrupt discontinuation should be avoided due to risk of seizures and severe withdrawal; tapering must be gradual.

• A. Switching to another benzodiazepine does not address dependence and merely substitutes one habit-forming agent for another.
• C. Indefinite continuation perpetuates dependence and does not address the underlying anxiety disorder with evidence-based therapy.
• D. Increasing the dose worsens tolerance and dependence rather than resolving the underlying problem.

Social anxiety disorder (social phobia) is characterized by marked fear or anxiety about social situations in which the person may be scrutinized or negatively evaluated by others, such as public speaking, eating in front of others, or interacting in groups, lasting 6 months or more and causing functional impairment. This patient's fear is specifically tied to social evaluation across multiple situations, not to a single discrete object or situation as seen in specific phobia. Agoraphobia involves fear of situations where escape might be difficult or help unavailable (such as crowds or open spaces), which this patient tolerates well, making it an unlikely diagnosis.

• B. Agoraphobia involves fear of crowds or places difficult to escape from, which this patient explicitly tolerates well.
• C. Specific phobia, situational type involves fear of a discrete situation (e.g., flying, elevators), not fear of social evaluation across multiple contexts.
• D. Specific phobia, natural environment type relates to fears such as heights or storms, which are not present here.

Selective serotonin reuptake inhibitors are first-line pharmacotherapy for obsessive-compulsive disorder, but higher doses than those used for depression are usually required for adequate anti-obsessional effect, and response may take 8-12 weeks. SSRI treatment is combined with CBT incorporating exposure and response prevention, which is the psychotherapy of choice. Benzodiazepines have no role as primary treatment, and antipsychotics are reserved as augmentation in treatment-resistant cases, not monotherapy.

• A. Standard depression doses are often subtherapeutic for OCD; higher doses are needed.
• B. Benzodiazepines are not effective for core obsessive-compulsive symptoms and risk dependence.
• D. Antipsychotics are used only as augmentation in resistant OCD, not as first-line monotherapy.

Acute stress reaction is a transient response to severe psychological or physical stress that typically resolves within hours to a few days with supportive measures. Initial management focuses on ensuring safety, providing a calm environment, brief psychological first aid, and reassurance, avoiding unnecessary sedation or medicalization. Pharmacotherapy and formal diagnoses like PTSD are not appropriate at this early stage since symptoms must persist beyond one month to meet PTSD criteria. Routine psychiatric hospitalization is not indicated unless there is risk to self or others.

• B. Involuntary admission is unwarranted without evidence of danger to self or others.
• C. Antipsychotics are not first-line and are reserved for severe agitation unresponsive to reassurance.
• D. PTSD cannot be diagnosed until symptoms persist beyond one month; medication is premature.

Acute dystonia is an early extrapyramidal side effect of antipsychotics, particularly high-potency typical agents like haloperidol, resulting from dopamine blockade in the nigrostriatal pathway causing a relative cholinergic excess. It presents with sustained muscle contractions such as oculogyric crisis or torticollis, usually within hours to days of starting treatment. Treatment is an anticholinergic or antihistaminic agent such intravenous or intramuscular benztropine or diphenhydramine, which rapidly reverses symptoms. Propranolol is used for akathisia, not dystonia, and dantrolene is reserved for neuroleptic malignant syndrome or malignant hyperthermia.

• B. Switching the antipsychotic does not address the acute emergency and delays relief.
• C. Dantrolene is used for neuroleptic malignant syndrome or malignant hyperthermia, not isolated dystonia.
• D. Propranolol is used for antipsychotic-induced akathisia, not acute dystonia.

This patient presents with neuroleptic malignant syndrome, characterized by fever, lead-pipe rigidity, autonomic instability, altered mental status, and markedly elevated creatine kinase, occurring as an idiosyncratic reaction to dopamine antagonists. Immediate management requires discontinuing the offending antipsychotic, aggressive supportive care with intravenous fluids and active cooling, and monitoring for rhabdomyolysis and renal failure. Dantrolene or bromocriptine may be added in severe or refractory cases. Continuing or increasing the antipsychotic worsens the condition and can be fatal.

• A. Administering more dopamine antagonist is dangerous and can precipitate fatal complications.
• C. Lithium does not treat neuroleptic malignant syndrome and is irrelevant to this acute presentation.
• D. Continuing or increasing the antipsychotic will worsen neuroleptic malignant syndrome and increase mortality risk.

Clozapine is indicated for treatment-resistant schizophrenia after failure of at least two adequate antipsychotic trials, but it carries a risk of agranulocytosis, a potentially fatal adverse effect. Regular full blood count monitoring with absolute neutrophil count is mandatory, typically weekly for the first 6 months, then less frequently, under a structured monitoring program. Liver function and lipid monitoring are relevant to overall metabolic safety but do not address the most serious, potentially fatal hematologic risk. Thyroid function is not specifically affected by clozapine.

• A. Thyroid function is not a recognized clozapine-specific monitoring requirement.
• B. Lipid monitoring is relevant to metabolic side effects, not the life-threatening hematologic risk.
• C. Liver function tests are not the primary mandated monitoring for clozapine's most serious adverse effect.

Atypical antipsychotics, especially olanzapine and clozapine, carry a high risk of weight gain, dyslipidemia, and new-onset diabetes. Guidelines recommend baseline assessment of weight, waist circumference, blood pressure, fasting glucose, and lipid profile, with weight checked frequently (weekly to monthly) during the first 12 weeks when gain is fastest, and metabolic labs repeated at 12 weeks and then annually. Early detection allows lifestyle intervention or switching agents before metabolic syndrome becomes established. Waiting for symptoms delays intervention since hyperglycemia and dyslipidemia are often asymptomatic initially.

• A. ECG monitors QT prolongation, not metabolic syndrome, and is not needed this frequently for olanzapine.
• B. Prolactin relates to risperidone-type side effects, not the metabolic syndrome being screened for here.
• D. Waiting for symptoms misses the asymptomatic phase when intervention is most effective.

Delusional disorder is characterized by one or more non-bizarre delusions lasting at least one month, in the absence of prominent hallucinations, disorganized speech, grossly disorganized behavior, or negative symptoms, with otherwise preserved functioning outside the delusion's direct impact. This patient's isolated persecutory delusion with intact occupational and social functioning fits this pattern. Schizophrenia requires additional psychotic features and functional decline across domains, which are absent here. The duration and isolated nature of the belief also exclude the shorter psychotic disorders.

• A. Brief psychotic disorder lasts less than 1 month, far shorter than this patient's 7-month course.
• B. Schizophrenia requires other psychotic features such as hallucinations or disorganization plus significant functional decline, neither present here.
• C. Schizophreniform disorder requires schizophrenia-like symptoms lasting 1-6 months with eventual return to baseline, not an isolated fixed delusion persisting unchanged.

Mild-to-moderate alcohol withdrawal typically begins 6-24 hours after the last drink with autonomic hyperactivity and tremor, as seen in this patient. Benzodiazepines are first-line therapy because they cross-tolerate with alcohol at the GABA-A receptor, reducing the risk of progression to seizures or delirium tremens. Symptom-triggered dosing using a validated scale such as CIWA-Ar, with an agent like lorazepam or chlordiazepoxide, is preferred over fixed dosing as it individualizes treatment and reduces total benzodiazepine exposure. Antipsychotics are reserved for refractory agitation and do not prevent seizures.

• A. Ethanol infusion is not a recommended treatment for withdrawal due to toxicity risk and lack of guideline support.
• B. Phenytoin is not effective for alcohol withdrawal seizures and is not part of standard withdrawal protocols.
• C. Haloperidol does not address the underlying GABA-ergic mechanism and lowers the seizure threshold.

Delirium tremens is a medical emergency characterized by autonomic instability, confusion, hallucinations, and seizure risk, typically emerging 48-96 hours after the last drink. Intravenous benzodiazepines are first-line, titrated aggressively to control agitation and autonomic hyperactivity, and patients require close monitoring for respiratory depression, cardiovascular instability, and recurrent seizures, often in a high-dependency or intensive care setting. Oral fixed dosing is inadequate for this severity and does not allow rapid titration. Delaying treatment for psychiatric consultation risks further seizures, cardiovascular collapse, or death.

• A. Fixed oral dosing cannot be titrated quickly enough for the severity of symptoms seen in established delirium tremens.
• C. Antipsychotics alone do not treat the underlying GABA deficiency and lower the seizure threshold, worsening seizure risk.
• D. Delirium tremens is a medical emergency requiring immediate pharmacologic treatment, not delay for consultation.

This patient has features suggestive of Wernicke's encephalopathy, which requires thiamine as a cofactor for glucose metabolism in the central nervous system. Administering glucose before thiamine in a thiamine-deficient patient can precipitate or worsen Wernicke's encephalopathy by depleting remaining thiamine stores during glucose metabolism. Thiamine should therefore be given intravenously before or simultaneously with dextrose, not after. Imaging is not needed before emergency correction of a reversible biochemical and nutritional derangement.

• A. Pyridoxine (vitamin B6) is not relevant to Wernicke's encephalopathy, which results from thiamine (vitamin B1) deficiency.
• B. Giving dextrose before thiamine in a thiamine-deficient patient can precipitate or worsen Wernicke's encephalopathy.
• C. Imaging is not required to make this diagnosis and would delay urgent treatment of both hypoglycemia and suspected thiamine deficiency.

Naloxone is a competitive opioid receptor antagonist and is first-line treatment for suspected opioid overdose presenting with respiratory depression and miosis. Standard dosing is 0.4-2 mg intravenously (or intramuscularly/intranasally if no IV access), repeated every 2-3 minutes as needed because naloxone has a shorter half-life than most opioids and repeat or higher doses may be required, especially with long-acting or synthetic opioids. Treatment should not be delayed pending laboratory confirmation when the clinical picture is consistent with opioid toxicity. Flumazenil reverses benzodiazepines, not opioids, and is not indicated here.

• A. Flumazenil is used for benzodiazepine, not opioid, reversal and is not indicated in this presentation.
• C. Naloxone should be given immediately based on the clinical picture; waiting for blood gas results delays life-saving treatment.
• D. A single large bolus without titration increases the risk of acute withdrawal and is not the standard approach; incremental dosing is preferred.

Opioid withdrawal typically develops within 6-24 hours after the last dose of a short-acting opioid and presents with a cluster of autonomic and gastrointestinal features: lacrimation, rhinorrhea, yawning, piloerection, mydriasis, myalgia, abdominal cramps, diarrhea, and mild hypertension with tachycardia. This contrasts sharply with opioid intoxication, which causes miosis, respiratory depression, and sedation. The timing after last use and the symptom cluster described are classic for withdrawal rather than intoxication or a different substance's withdrawal syndrome.

• A. Alcohol withdrawal typically features tremor and can progress to seizures or hallucinations, not the gastrointestinal and secretory symptom cluster described.
• B. Stimulant intoxication causes mydriasis and tachycardia but not the lacrimation, rhinorrhea, and gastrointestinal cramping characteristic of opioid withdrawal.
• D. Opioid intoxication causes miosis and respiratory depression, the opposite of the mydriasis and hyperactivity seen here.

Delirium is characterized by an acute onset (hours to days), a fluctuating course often worse at night (sundowning), and a core deficit in attention and awareness, frequently with an identifiable precipitant such as infection or medication. Dementia, in contrast, develops gradually over months to years, typically with preserved alertness and attention until late stages, and a relatively stable day-to-day course. This patient's abrupt 2-day change with fluctuating attention is classic for delirium, often triggered by an underlying acute medical illness that requires urgent evaluation. Attention is the key bedside feature that differentiates the two conditions.

• A. Gradual onset over years describes dementia, the opposite of this patient's presentation.
• B. Delirium characteristically fluctuates during the day rather than remaining stable, unlike the pattern described in this option.
• C. Progressive memory loss with preserved alertness describes dementia, whereas this patient has impaired attention and fluctuating alertness.

Donepezil, a cholinesterase inhibitor, is first-line therapy for mild to moderate Alzheimer's disease, working by increasing synaptic acetylcholine to partially compensate for cholinergic neuron loss. It can produce modest improvement or slow decline in cognition and daily function. Memantine, an NMDA receptor antagonist, is reserved for moderate to severe disease, often added once cholinesterase inhibitors alone are insufficient. Antipsychotics and antidepressants have no role in treating core cognitive symptoms and are only considered for specific behavioral or mood symptoms when they arise.

• A. Memantine is indicated for moderate to severe Alzheimer's disease, not as initial therapy in mild-to-moderate stages.
• B. Sertraline treats depression or anxiety symptoms but does not address the underlying cognitive decline of Alzheimer's disease.
• C. Risperidone has no role in treating cognitive decline and is reserved for severe behavioral disturbance with risk of harm.

The triad of gait disturbance, urinary incontinence, and cognitive decline strongly suggests normal pressure hydrocephalus, a reversible cause of dementia. Brain MRI showing ventriculomegaly disproportionate to cortical atrophy is the key investigation to establish this diagnosis and guide further workup with lumbar puncture or CSF tap test. While B12 deficiency, hypothyroidism, and neurosyphilis are also reversible causes of cognitive decline screened for in dementia workup, they do not typically present with this specific gait-incontinence-cognitive triad, making MRI the most directed next investigation here.

• B. Vitamin B12 deficiency causes cognitive decline and peripheral neuropathy but does not typically produce this gait-incontinence triad.
• C. Hypothyroidism can cause cognitive slowing but does not explain the combination of gait disturbance and urinary incontinence.
• D. Neurosyphilis can cause dementia but classically presents with other neurological findings, not this specific clinical triad.

Non-pharmacologic strategies, including structured daily routines, adequate lighting, reducing evening stimulation, and addressing unmet needs, are first-line for managing behavioral and psychological symptoms of dementia such as sundowning and agitation, particularly when symptoms are mild and non-aggressive. Antipsychotics carry increased risks of stroke and mortality in elderly dementia patients and should be reserved for severe agitation, aggression, or psychosis unresponsive to behavioral measures. Physical restraints are inappropriate and can worsen agitation and cause injury. A reversible precipitant such as infection or pain should also be excluded before escalating treatment.

• B. Physical restraint is inappropriate, can increase agitation and injury risk, and is not a recommended management strategy.
• C. Quetiapine carries similar risks to other antipsychotics and is not appropriate as initial management for mild symptoms.
• D. Antipsychotics increase cardiovascular and mortality risk in elderly dementia patients and should not be first-line for mild, non-aggressive agitation.

UAE mental health law permits involuntary admission when a qualified psychiatrist assesses that a person has a mental disorder and that, as a result, there is a significant risk of harm to the patient or others, combined with lack of capacity or refusal of necessary treatment. This assessment must be documented by an authorized mental health professional, with safeguards including time-limited detention, periodic review, and the right to appeal. Family request alone, without psychiatric assessment confirming risk, is insufficient legal grounds. Police involvement may assist in bringing a patient to care but does not substitute for the required psychiatric evaluation establishing the statutory criteria.

• A. UAE law does not require a seven-day waiting period before emergency involuntary admission when imminent risk is present.
• B. Family wishes alone, without psychiatric confirmation of mental disorder and risk, do not meet the legal threshold for involuntary admission.
• C. Police can facilitate transport to care but cannot authorize involuntary admission without psychiatric assessment.

Acute onset of confusion with fluctuating attention and altered level of consciousness in an elderly patient with fever and tachycardia is characteristic of delirium, most often caused by an underlying medical condition such as infection. Before attributing new psychiatric symptoms to a primary psychiatric disorder, organic causes (infection, metabolic derangement, hypoxia, drug toxicity, intracranial pathology) must be excluded, especially in older adults or those with acute onset, fluctuating course, or abnormal vital signs. Here the urine findings suggest a urinary tract infection as a likely precipitant of delirium. Management should prioritize identifying and treating the underlying cause rather than empiric psychiatric treatment.

• A. Antipsychotics may be used cautiously for agitation but treating the underlying medical cause takes priority, and psychiatric admission is inappropriate before organic causes are excluded.
• B. Delirium is a medical emergency requiring prompt evaluation, not deferred outpatient follow-up.
• C. The acute fluctuating presentation with fever and tachycardia is not consistent with primary depression; this would delay identification of a treatable organic cause.

Somatic symptom disorder is characterized by one or more distressing physical symptoms accompanied by excessive thoughts, feelings, or behaviors related to the symptoms, such as disproportionate anxiety about illness, persistent health-related concerns, and excessive time or energy devoted to the symptoms, lasting more than six months. The patient genuinely believes he is unwell and is not fabricating symptoms or seeking external gain, distinguishing this from factitious disorder and malingering. Extensive negative workups do not reassure the patient, which is a hallmark feature. Management focuses on a strong therapeutic alliance, regular scheduled visits, and cognitive behavioral therapy rather than repeated investigations.

• A. Malingering involves conscious fabrication of symptoms for external gain such as financial compensation or avoiding work duties, which is specifically denied here.
• B. Factitious disorder involves intentional falsification or induction of symptoms to assume the sick role, not genuine belief in organic illness.
• C. Conversion disorder involves neurological symptoms incompatible with recognized disease, not abdominal pain with associated health anxiety.

Anorexia nervosa causes a hypometabolic state leading to bradycardia, hypotension, and electrolyte disturbances such as hypokalemia and hypomagnesemia, which predispose to QT prolongation and potentially fatal arrhythmias. Bradycardia (heart rate often less than 60/min, sometimes much lower) is one of the most consistent cardiovascular findings and a key indicator of medical instability requiring hospitalization. Electrocardiogram monitoring for QT prolongation is essential because of the arrhythmia risk, particularly during refeeding. Clinicians should also check serum electrolytes, including potassium, magnesium, and phosphate.

• A. Left ventricular hypertrophy is not expected; anorexia nervosa is more associated with reduced cardiac mass and myocardial atrophy.
• B. Atrial fibrillation is not a characteristic complication of anorexia nervosa.
• C. Sinus tachycardia is not typical; the hypometabolic adaptation in anorexia nervosa classically causes bradycardia.

Refeeding syndrome results from a sudden shift from catabolism to anabolism when nutrition is reintroduced in severely malnourished patients, causing intracellular shifts of phosphate, potassium, and magnesium driven by insulin release, which can lead to severe hypophosphatemia, cardiac arrhythmias, and death. Prevention requires starting nutrition at a conservative caloric level, typically well below full estimated requirements, with gradual increases over days while closely monitoring and replacing electrolytes, especially phosphate. Thiamine supplementation is also recommended before and during refeeding to prevent Wernicke encephalopathy. Rapid full-calorie feeding significantly increases the risk of this complication.

• A. Starting at full caloric requirements markedly increases the risk of refeeding syndrome in severely malnourished patients.
• B. Dextrose boluses provide a large glucose load that can precipitate insulin surges and worsen electrolyte shifts, increasing refeeding syndrome risk.
• C. Fluid restriction is not the preventive strategy for refeeding syndrome; careful fluid balance is important but electrolyte monitoring and cautious caloric advancement are key.

This patient's pattern of unstable relationships, impulsivity, recurrent self-harm, identity disturbance, chronic emptiness, and fear of abandonment meets criteria for borderline personality disorder. Dialectical behavior therapy, developed specifically for this condition, is the first-line evidence-based psychotherapy and combines individual therapy, group skills training, and crisis coaching to improve emotion regulation and reduce self-harm. Pharmacotherapy has only a limited adjunctive role for specific symptoms such as mood lability and is not considered first-line primary treatment. Long-term hospitalization is generally avoided as it can reinforce maladaptive behaviors and dependency.

• A. Long-term inpatient admission is not recommended as first-line management and may worsen dependency and regression.
• B. Medications are not first-line and are used only as adjuncts for specific symptom clusters, not as monotherapy for the disorder itself.
• D. Electroconvulsive therapy has no established role in the treatment of borderline personality disorder.

This child demonstrates symptoms of inattention and hyperactivity-impulsivity present in multiple settings (school and home) for more than six months, consistent with attention-deficit/hyperactivity disorder. First-line pharmacologic treatment for school-age children with ADHD, when behavioral therapy alone is insufficient, is a stimulant medication such as methylphenidate, which improves core symptoms of inattention, hyperactivity, and impulsivity by increasing dopamine and norepinephrine availability in the prefrontal cortex. Behavioral therapy and parent training should always accompany or precede medication, particularly in young children. Growth, appetite, and cardiovascular status should be monitored during treatment.

• B. Diazepam is a benzodiazepine with no role in ADHD management and carries risk of sedation and dependence in children.
• C. Fluoxetine is a selective serotonin reuptake inhibitor used for depression and anxiety disorders, not a first-line ADHD treatment.
• D. Risperidone is an antipsychotic used for disruptive behavior or aggression in certain disorders, not first-line for ADHD.

The combination of intense nocturnal pruritus, characteristic burrows in finger web spaces and flexor wrists, and symptomatic household contacts strongly suggests scabies, caused by infestation with the mite Sarcoptes scabiei. First-line treatment is topical permethrin 5% cream applied to the entire body from the neck down (or entire body including scalp in infants), left on for 8 to 14 hours, and repeated after one week to kill any newly hatched mites. All household and close contacts should be treated simultaneously regardless of symptoms to prevent reinfestation, and bedding and clothing should be washed in hot water. Oral ivermectin is an alternative, particularly for crusted scabies or outbreak settings.

• A. Clotrimazole is an antifungal agent with no activity against the scabies mite.
• C. Doxycycline is an antibiotic with no role in treating scabies infestation.
• D. Calamine lotion may relieve itching symptomatically but does not eradicate the mite infestation and is not a definitive treatment.

Impetigo is most commonly caused by Staphylococcus aureus (and occasionally Streptococcus pyogenes). For localized, limited impetigo, topical mupirocin is first-line therapy because it is effective against both organisms and avoids the adverse effects and resistance pressure of systemic antibiotics. Oral antibiotics are reserved for widespread lesions, systemic symptoms, or treatment failure. Clotrimazole is an antifungal and has no role in bacterial skin infection.

• B. Clotrimazole is an antifungal agent and does not treat bacterial impetigo.
• C. Clindamycin is an alternative oral option for extensive disease, not first-line for localized lesions.
• D. Oral cephalexin is reserved for extensive or systemic disease, not localized impetigo.

The combination of pain out of proportion to clinical findings, skin discoloration, hemorrhagic bullae, rapid progression, and systemic toxicity (hypotension, tachycardia, fever) are red-flag features of necrotizing fasciitis rather than simple cellulitis. This is a surgical emergency requiring urgent exploration and debridement, as imaging or antibiotics alone cause dangerous delay. Broad-spectrum intravenous antibiotics should be started immediately but do not replace surgery, which is both diagnostic and therapeutic.

• A. Imaging may support the diagnosis but should never delay definitive surgical management when clinical suspicion is high.
• C. Oral antibiotics and outpatient follow-up are inadequate for a patient with signs of septic shock and suspected necrotizing infection.
• D. Conservative measures like compression and elevation are inappropriate and dangerous in a necrotizing soft tissue infection.

Herpes zoster results from reactivation of latent varicella-zoster virus in a dorsal root ganglion, producing a dermatomal vesicular rash often preceded by neuropathic pain. Oral antiviral therapy (acyclovir, valacyclovir, or famciclovir) started within 72 hours of rash onset reduces the severity and duration of the rash and lowers the risk of postherpetic neuralgia. Beyond 72 hours, antivirals may still be considered if new vesicles are forming or in high-risk patients, but benefit is less certain. Topical antivirals are not effective for zoster.

• A. Untreated zoster carries a higher risk of postherpetic neuralgia, especially in older patients; antiviral therapy is indicated.
• B. Topical acyclovir has no proven efficacy in herpes zoster and is not a substitute for systemic therapy.
• D. Delaying treatment until crusting reduces the benefit of antiviral therapy, which is greatest within the first 72 hours.

Molluscum contagiosum is a benign viral skin infection caused by a poxvirus, common in children, and spread by direct contact or autoinoculation. In immunocompetent children with asymptomatic, uncomplicated lesions, the natural history is spontaneous resolution over months to a couple of years, so reassurance and observation is the preferred first-line approach. Active treatments such as cryotherapy or curettage are reserved for cosmetically bothersome, extensive, or persistent lesions, or if requested by the family after discussion. Antivirals have no role since this is a poxvirus, not a herpesvirus.

• B. Acyclovir targets herpesviruses and has no activity against the poxvirus causing molluscum contagiosum.
• C. Routine surgical excision is unnecessary and overly invasive for a self-limiting benign condition.
• D. Immediate cryotherapy of every lesion is not first-line; it is reserved for selected cases and can cause scarring and pain in young children.

Pediculosis capitis (head lice) is treated first-line with topical permethrin 1%, which is applied to damp hair, left on for the recommended time, and typically repeated after 7-9 days to kill newly hatched lice. It has a favorable safety profile for use in children and is widely available over the counter. Oral ivermectin is reserved for treatment failures or resistant cases. Antifungal shampoos and antibiotics have no role since lice are an ectoparasite infestation, not a fungal or bacterial infection.

• B. Ketoconazole shampoo treats fungal infections and has no effect on lice.
• C. Doxycycline is an antibiotic and has no role in treating an ectoparasite infestation.
• D. Oral ivermectin is a second-line option used when topical treatment fails or is impractical, not first-line.

Atopic dermatitis is managed in a stepwise fashion: regular emollients form the foundation of care, and when itching and inflammation persist despite adequate emollient use, a topical corticosteroid of appropriate potency is added for the affected areas. In children, especially on sensitive skin, a low-potency corticosteroid is typically chosen first, escalating potency only if control is inadequate. Systemic therapy is reserved for severe, refractory disease unresponsive to topical measures.

• B. Continuing emollients alone when symptoms are worsening delays effective control of inflammation.
• C. Oral corticosteroids carry significant side effects and are not indicated for mild-to-moderate eczema that has not failed topical therapy.
• D. Systemic immunosuppressants are reserved for severe, treatment-resistant atopic dermatitis, not as an early step.

This presentation, itchy vesicular dermatitis sharply localized to sites of jewelry contact, is characteristic of allergic contact dermatitis, a type IV (delayed, cell-mediated) hypersensitivity reaction. Patch testing with a standardized allergen series, which includes nickel sulfate, is the diagnostic test of choice to identify the specific contact allergen and confirm the clinical suspicion. Skin prick testing and serum IgE assess type I immediate hypersensitivity reactions and are not useful for delayed contact dermatitis. Biopsy can support a diagnosis of dermatitis in general but cannot identify the specific causative allergen.

• A. Total IgE reflects atopic or immediate allergic tendency and does not identify a specific contact allergen.
• B. Skin prick testing evaluates immediate (type I) hypersensitivity and is not useful for delayed-type contact dermatitis.
• C. Biopsy may show nonspecific eczematous changes but cannot pinpoint the causative allergen.

Seborrheic dermatitis typically affects sebaceous gland-rich areas such as the scalp, eyebrows, nasolabial folds, and ears, with greasy yellow scaling on an erythematous base. The condition is linked to Malassezia yeast overgrowth and skin barrier dysfunction, so topical antifungals such as ketoconazole are first-line therapy. They reduce fungal colonization and have anti-inflammatory properties, making them effective and safe for long-term intermittent use on the face.

• A. Oral antifungals are reserved for severe or refractory cases, not first-line therapy.
• C. Potent topical steroids are not first-line on the face due to risk of atrophy and rebound; they are used short-term for severe flares only.
• D. Topical calcineurin inhibitors are second-line, used when antifungals fail or for steroid-sparing maintenance.

Prolonged or inappropriate use of potent topical corticosteroids, particularly on thin-skinned areas like the face, causes cutaneous atrophy. Corticosteroids suppress fibroblast proliferation and reduce collagen and glycosaminoglycan synthesis in the dermis, leading to thinning, striae, telangiectasia, and increased fragility with easy bruising. This is a well-recognized dose- and duration-dependent adverse effect, and risk is minimized by using the lowest effective potency for the shortest necessary duration, especially on the face and flexures.

• A. Mast cell degranulation underlies urticaria and allergic reactions, not steroid-induced atrophy.
• B. Allergic contact dermatitis to steroids presents as treatment-resistant eczema, not atrophic thinning.
• C. Follicular plugging describes comedone formation in steroid acne, not atrophy and telangiectasia.

This patient has clinical features of Stevens-Johnson syndrome: mucocutaneous blistering, positive Nikolsky sign, and mucosal involvement following a new culprit drug. The single most important immediate action is prompt withdrawal of the suspected causative drug, as continued exposure worsens prognosis and increases mortality. Patients with significant body surface area involvement require urgent referral to a burns unit or specialized dermatology/intensive care setting for fluid management, wound care, and monitoring for complications.

• A. This is a dermatologic emergency requiring specialist inpatient care, not outpatient management with topical antibiotics.
• B. Dose reduction does not eliminate the immunologic trigger and risks progression to toxic epidermal necrolysis.
• D. Continuing the causative drug while adding steroids delays the most critical intervention, which is withdrawal of the offending agent.

Allopurinol is one of the most frequently implicated drugs worldwide in causing Stevens-Johnson syndrome and toxic epidermal necrolysis, particularly in patients carrying the HLA-B*58:01 allele, which is more prevalent in certain Asian populations. The reaction is a delayed T-cell-mediated hypersensitivity response typically occurring within the first few weeks of starting therapy. Other high-risk drug classes include aromatic anticonvulsants (carbamazepine, phenytoin, lamotrigine) and sulfonamide antibiotics.

• A. NSAIDs carry a lower relative risk of SJS/TEN compared to allopurinol.
• C. Colchicine is not a recognized major cause of SJS/TEN.
• D. Probenecid is not classically associated with SJS/TEN.

Erythema multiforme is characteristically associated with herpes simplex virus infection (preceding cold sores) rather than drugs, and presents with classic three-zone target lesions distributed acrally on extensor surfaces of the limbs. Mucosal involvement, when present, is typically mild and limited to one site, and there is minimal or no skin detachment. This contrasts with SJS/TEN, which is usually drug-induced, affects the trunk more diffusely, and involves more severe mucosal erosions with skin detachment correlating with body surface area involved.

• A. TEN involves greater than 30% body surface area with extensive epidermal detachment, far more severe than this presentation.
• B. SJS typically follows drug exposure, involves the trunk and face with more severe mucosal erosions, and shows skin detachment.
• D. Bullous pemphigoid presents with tense subepidermal bullae in older adults, not target lesions following a viral trigger.

This lesion demonstrates multiple ABCDE criteria for melanoma: asymmetry, border irregularity, color variegation, diameter greater than 6 mm, and evolution over time. The appropriate next step for a lesion suspicious for melanoma is excisional biopsy with narrow margins (typically 1-3 mm of normal skin), which allows full histopathological assessment including Breslow thickness to guide further management and definitive wide excision margins. Shave or punch biopsies are avoided as they may miss the deepest point of invasion.

• B. Imiquimod is used for superficial basal cell carcinoma or actinic keratosis, not suspected melanoma.
• C. Destructive techniques like cryotherapy destroy tissue needed for histological diagnosis and staging.
• D. Delaying evaluation risks disease progression; any lesion meeting ABCDE criteria warrants prompt tissue diagnosis.

The lesion described, a pearly papule with rolled borders, telangiectasia, and central ulceration, is the classic appearance of basal cell carcinoma, the most common skin cancer. Cumulative ultraviolet radiation exposure, particularly in fair-skinned individuals with significant outdoor sun exposure over decades, is the most important risk factor, causing DNA damage in basal keratinocytes and mutations in the sonic hedgehog signaling pathway. Other risk factors include increasing age, immunosuppression, and prior radiation exposure.

• A. Hepatitis C is associated with conditions like porphyria cutanea tarda and lichen planus, not basal cell carcinoma.
• B. Chronic venous insufficiency is linked to venous ulcers, not basal cell carcinoma.
• D. HPV is associated with squamous cell carcinoma and anogenital/cervical cancers, not basal cell carcinoma.

Actinic keratosis results from ultraviolet-induced DNA damage (particularly p53 mutations) in epidermal keratinocytes, producing a clonal population of atypical cells confined to the epidermis, a form of in-situ carcinogenesis. A subset of untreated lesions progress to invasive squamous cell carcinoma once atypical cells breach the basement membrane, which is why actinic keratosis is considered a precursor lesion. Management includes cryotherapy, topical 5-fluorouracil, imiquimod, or photodynamic therapy, along with strict photoprotection to reduce further UV-induced mutagenesis. Clinically, lesions feel rough and gritty due to overlying hyperkeratosis rather than true dermal thickening.

• A. This describes the mechanism of melanoma in situ (lentigo maligna), not actinic keratosis.
• C. This describes HPV-related verrucae or Bowenoid papulosis mechanisms, not UV-induced actinic keratosis.
• D. Actinic keratosis is driven by UV-induced keratinocyte atypia, not a granulomatous inflammatory process.

Vitiligo is an autoimmune disorder caused by destruction of melanocytes, and it is strongly associated with other autoimmune conditions, most commonly autoimmune thyroid disease (Hashimoto thyroiditis or Graves disease), affecting up to 20-30% of patients. The diagnosis is usually clinical, supported by Wood's lamp accentuation of depigmented macules, and this patient's fatigue and palpitations raise suspicion for thyroid dysfunction, making thyroid function tests and thyroid autoantibodies the appropriate next step. Skin biopsy is rarely needed since the clinical picture and Wood's lamp findings are characteristic. Screening for associated autoimmune disease is a key part of vitiligo management, not just treatment of the skin lesions.

• A. Systemic corticosteroids are not first-line and are not indicated before addressing symptoms suggesting underlying thyroid disease.
• B. Biopsy is reserved for atypical or diagnostically uncertain cases; this presentation is classic for vitiligo.
• D. An ANA/dsDNA panel screens for lupus, which is not the autoimmune condition most strongly linked to vitiligo.

Isotretinoin is a potent human teratogen that causes severe fetal malformations (craniofacial, cardiac, CNS defects) and spontaneous abortion, so pregnancy must be excluded before starting therapy and prevented throughout treatment and for at least one month afterward. Current guidelines (including iPLEDGE and UK/European pregnancy prevention programs) recommend a negative pregnancy test immediately before starting and monthly during treatment, combined with two reliable forms of contraception in sexually active women of childbearing potential. Baseline bloods (liver function, lipids) are also checked but do not substitute for pregnancy prevention counseling. Isotretinoin is absorbed systemically and its teratogenic risk is independent of acne severity or route of administration being oral.

• A. Isotretinoin is systemically absorbed and highly teratogenic; barrier contraception alone is not considered adequate protection.
• B. Liver function tests are part of baseline monitoring but checking them alone ignores the critical teratogenic risk that must be addressed first.
• C. Waiting for a missed period risks starting isotretinoin during an undetected early pregnancy, when organogenesis is already underway.