Disruptive mood dysregulation disorder — formative SAQs

SAQ 1 (10 marks)

An eight-year-old boy has severe temper outbursts three to four times a week at home and at school, grossly out of proportion to the trigger, and is described by both parents and teachers as "always angry, easily annoyed, and grouchy most of the day, every day." This pattern has been present for fourteen months with no clear break, began around age six, and is disrupting his learning and friendships. There is no history of distinct elevated-mood episodes, no sleep reduction, no psychosis, and no disclosed abuse. [1] [2]

1. Give the most likely diagnosis with the criteria that support it, and state the most important condition to exclude before labelling it. (4) [1]
2. List three differential diagnoses with a discriminator for each. (3) [2]
3. Outline the first-line management plan and explain why medication is not the routine first step. (3) [4]

Model answer — SAQ 1

(1) Diagnosis and the must-exclude condition (4). The picture fits disruptive mood dysregulation disorder (DMDD): severe, recurrent temper outbursts grossly out of proportion and inconsistent with developmental level, occurring at least three times a week; a chronic, irritable or angry mood most of the day, nearly every day; onset before age ten; duration at least twelve months with no symptom-free stretch over three months; present in two or more settings (home and school) and impairing. The single most important condition to exclude before labelling it is paediatric bipolar disorder — ask explicitly for any distinct period of elevated or expansive mood with decreased need for sleep, racing thoughts and grandiosity. [1] [3]

(2) Differentials with discriminators (3). ODD: a pattern of angry/irritable mood plus argumentative, defiant or vindictive behaviour, but without the severe frequent outbursts and chronic sustained baseline of DMDD; if both criteria are met, assign DMDD only. ADHD: chronic inattention, hyperactivity and impulsivity with secondary frustration, but irritability is not the sustained core. Intermittent explosive disorder: discrete outbursts without the chronic between-outburst baseline irritability, and mutually exclusive with DMDD. A comorbid depressive or anxiety disorder and an organic or substance cause should also be considered. [2]

(3) First-line management and why not medication first (3). First-line is structured parent training (PCIT, Triple P, Coping Power) plus child emotion-regulation CBT, with a school-based behaviour plan and psychoeducation. Medication is not the routine first step because the meta-analytic evidence shows the most consistent benefit for psychosocial interventions, while drugs carry smaller, less consistent effects and side-effect burdens; drugs are adjunctive and target a comorbidity (ADHD, depression, anxiety) or short-term dangerous aggression. [4]

SAQ 2 (10 marks)

A ten-year-old girl with established DMDD and comorbid ADHD is on a stable parent-training and CBT programme but remains significantly impaired by outbursts. Her parents ask whether a medicine would now help. She has no history of manic episodes, no psychosis, normal growth, and no disclosed self-harm. [4] [5]

1. State which medication is most evidence-supported in this combined picture, with the key monitoring requirement. (4) [5]
2. Explain two scenarios in which an antidepressant or an antipsychotic might be considered, and the safeguards for each. (4) [4]
3. Describe how you would build a relapse-prevention and review plan. (2) [4]

Model answer — SAQ 2

(1) Evidence-supported medication and monitoring (4). In DMDD with comorbid ADHD, a CNS stimulant is the best-supported pharmacological option: treating the ADHD often reduces the irritability load, and the Baweja study showed stimulants were effective and tolerable in children with both ADHD and DMDD. The key monitoring requirement is close observation for mood worsening, new agitation or behavioural activation, plus appetite, sleep, growth and cardiovascular baseline, with early review after starting or changing dose. The DMDD label itself never justifies a stimulant — the target is the comorbid ADHD. [5]

(2) Antidepressant and antipsychotic scenarios with safeguards (4). An antidepressant (e.g. fluoxetine) is considered only when a comorbid depressive or anxiety disorder meets full criteria, treated psychotherapy-first and with fluoxetine if a drug is indicated, always after excluding bipolar; start low, review early for activation and suicidality. An antipsychotic (e.g. risperidone) is considered only short-term for severe, dangerous aggression not contained by behaviour therapy, with specialist input, a defined target and duration, baseline metabolic monitoring (weight, BMI, glucose, lipids), and a taper plan. Neither is a routine first-line treatment for DMDD itself. [4]

(3) Relapse-prevention and review plan (2). Agree written early-warning signs, the strategies that worked (parent-training responses and the child's coping skills), the professional contact for escalation, and a named coordinator. Set a clear early review after any medication change and a periodic review to reassess comorbidity, function and side effects, and to plan transition to adolescent services in advance. [4] [6]