🧠 Chapter 27: Unusual Behaviors

Nelson's Pediatric Symptom-Based Diagnosis | ADHD · Tic Disorders · OCD · Anxiety · Depression · PTSD · Anorexia Nervosa · Psychosis · Suicide Risk

🔍 Unusual Behaviors in Children: Key Concepts

📊 ADHD (Attention-Deficit/Hyperactivity Disorder)
Inattention, hyperactivity, impulsivity. Symptoms ≥6 months, present in ≥2 settings, onset <12 years. Subtypes: combined, inattentive, hyperactive-impulsive. Comorbid: learning disorders, ODD, anxiety.
🔄 Tic Disorders & Tourette
Simple motor tics (blinking), complex (jumping), vocal (throat clearing). Tourette: ≥2 motor + ≥1 vocal tic >1 year, onset <18 years. Often with ADHD, OCD.
⚠️ Disruptive Behaviors (ODD, Conduct Disorder)
ODD: angry/irritable mood, argumentative, vindictive (≥4 symptoms). Conduct disorder: aggression, property destruction, deceitfulness, rule violations (≥3 in 12 mo).
💧 Mood Disorders (Depression, Bipolar)
Major depression: depressed/irritable mood, anhedonia, ≥5 symptoms for ≥2 weeks. Bipolar I: manic episode (≥1 week). Bipolar II: hypomania + major depression. Screen for suicidality.
🧬 Anxiety Disorders & OCD
Generalized anxiety (excessive worry), social anxiety (fear of scrutiny), separation anxiety. OCD: obsessions + compulsions (>1 hour/day). PANDAS (controversial).
🚩 Eating Disorders & Suicide
Anorexia nervosa: restricted intake, fear of weight gain, distorted body image, amenorrhea. Bulimia: binge-purge. Suicide: 2nd leading cause of death in adolescents. Screen with Columbia scale.

💡 Key Takeaway: Unusual behaviors in children often represent primary psychiatric disorders, but always rule out medical causes (thyroid, lead, seizures, substance use). Suicidal ideation is a medical emergency requiring immediate mental health evaluation.

🩺 Clinical Approach to Unusual Behaviors: Step-by-Step

🔹 Step 1: Ensure safety (suicide risk, danger to others)
• Ask directly: "Have you thought about killing yourself?" Columbia Suicide Severity Rating Scale.
• If suicidal ideation with plan/intent → emergency psychiatric evaluation, hospitalization.
• Assess for homicidal ideation, aggression, access to weapons.
🔹 Step 2: Rule out medical causes of behavioral change (MIDAS)
• Medications (steroids, stimulants, SSRIs, anticholinergics).
• Illness: thyroid (hyper/hypo), lead poisoning, Wilson disease, seizures, CNS infection/tumor.
• Drug use: amphetamines, cocaine, cannabis, alcohol, PCP.
• Laboratory: TSH, lead level, drug screen, LFTs, ammonia, ceruloplasmin if indicated.
🔹 Step 3: Characterize the behavior pattern
• Disruptive (violate rights): conduct disorder, ODD, ADHD.
• Mood: depression (sad, anhedonia, sleep/appetite changes), mania (grandiosity, decreased sleep, pressured speech).
• Anxiety: excessive worry, avoidance, panic attacks.
• Repetitive: tics, compulsions, rituals.
• Eating: anorexia, bulimia.
🔹 Step 4: Obtain collateral information
• Parents, teachers, school records.
• Standardized rating scales (Vanderbilt for ADHD, SCARED for anxiety, PHQ-9 for depression).
• DSM-5 criteria for specific disorders.
🔹 Step 5: Treatment and referral
• ADHD: stimulants (methylphenidate), behavioral therapy.
• Depression: CBT, SSRIs (fluoxetine, escitalopram) – monitor for suicidality.
• Anxiety: CBT, SSRIs.
• OCD: CBT (exposure/response prevention), SSRIs.
• Anorexia: family-based treatment (Maudsley), medical stabilization.
• Refer to child psychiatry if severe, complex, or not responding.