Melancholic vs atypical features — diagnosis and treatment (MEQ)

(i) Specifiers and hinge. Case A: major depressive episode with melancholic features (near-total anhedonia/nonreactivity, early waking, weight loss, psychomotor retardation, excessive guilt). Case B: major depressive episode with atypical features (mood reactivity present; reverse vegetative cluster; leaden paralysis; rejection sensitivity). Hinge: mood reactivity is required for atypical features and absent/near-absent for melancholia — do not dual-code conflicting reactivity. [5][7]

(ii) Differentials for Case B. (1) Bipolar depression — prior hypo/mania, mixed features, family history; reverse vegetative atypical features are common in bipolar depression. (2) Medical/sleep mimic — hypothyroidism, OSA (hypersomnia + weight gain), substances/medications. (3) Personality/anxiety overlap — trait rejection sensitivity and social anxiety can coexist; still require full MDE criteria rather than labelling only "personality." [5][7]

(iii) Case A management / ECT. Measurement-based adequate antidepressant trial with secondary-care intensity; suicide-risk and intake monitoring. Early ECT if food/fluid refusal, catatonia, psychosis, uncontainable risk, prior excellent ECT response, or too slow on medicines — UK ECT Review Group supports strong efficacy in severe depressive disorders; RANZCP frames early biological intensity for severe melancholia. Name agents if pharmacotherapy first (e.g. venlafaxine XR start 75 mg oral daily titrating; sertraline 50 mg oral daily titrating) with monitoring. [4][5]

(iv) Case B management. Start modern first-line antidepressant and/or evidence-based psychotherapy (CBT/IPT; behavioural activation); Jarrett supports cognitive therapy as active treatment versus placebo alongside phenelzine. Historical Columbia evidence: phenelzine preferential versus imipramine/placebo in atypical depression (Liebowitz; Quitkin). If phenelzine later used: start low (e.g. 15 mg oral daily building toward often 45–90 mg/day divided), tyramine diet, pharmacy flag, never combine with SSRI/SNRI/clomipramine/tramadol; respect washouts (about 5 weeks after fluoxetine). [1][2][3][6][7]

(v) Pitfalls. Coding both melancholic and atypical when reactivity conflicts; treating atypical as mild/low-risk; delaying ECT in food-refusing melancholia; starting MAOI without diet/washout plan; missing bipolarity; using DST as a modern diagnostic gate. [5][6]