Chamberlain College of Nursing |
Differential Diagnosis in Psychiatric-
Mental Health | 50 Practice Questions,
Answers & Rationale
**Q1.** A 28-year-old graduate student presents with a 3-week
history of pervasive low mood, anhedonia, 10-lb weight loss,
and insomnia with early morning awakening. She endorses
passive suicidal ideation but has no plan. She reports a similar
but milder episode at age 19. Her physical exam and basic
metabolic panel are normal. During the interview, you note her
speech is pressured, she is distractible, and she reveals she has
been working on multiple creative projects simultaneously for
the past 5 days, feeling "like my brain is on fire and I don't need
sleep." What is the most accurate initial diagnosis?
A. Major Depressive Disorder, single episode, severe
B. Bipolar I Disorder, current episode depressed
C. Bipolar II Disorder, current episode depressed
D. Cyclothymic Disorder
,**Correct Answer: C**
**Rationale:** The patient meets criteria for a current Major
Depressive Episode. The key diagnostic feature is the reported
5-day period of hypomanic symptoms (decreased need for
sleep, increased goal-directed activity, distractibility, racing
thoughts). A full manic episode (Bipolar I) would cause marked
impairment or require hospitalization; this vignette describes
hypomania. Therefore, the history of a major depressive
episode and at least one hypomanic episode establishes Bipolar
II Disorder. Cyclothymia involves hypomanic and depressive
symptoms that do not meet full episode criteria.
**Q2.** A 45-year-old veteran presents with his wife. She
reports he is emotionally distant, irritable, and has severe
insomnia with nightmares. He startles excessively, avoids
crowded places, and has not visited friends since returning from
deployment 10 months ago. He denies depressed mood but
admits to constant hypervigilance and feeling "numb inside."
He meets full criteria for PTSD. On mental status exam, you note
a blunt affect, but he is fully oriented. His wife mentions he has
begun to repeatedly check that the stove is off before leaving
the house, a ritual that takes 30 minutes and causes arguments.
What is the most appropriate additional diagnosis to consider?
A. Illness Anxiety Disorder
B. Obsessive-Compulsive Disorder
,C. Generalized Anxiety Disorder
D. Adjustment Disorder with Anxiety
**Correct Answer: B**
**Rationale:** While OCD and PTSD are both trauma- and
stressor-related disorders in DSM-5-TR, they can be comorbid.
The presence of true obsessions (recurrent, intrusive thoughts
about the stove being on leading to anxiety) and compulsions
(the repetitive checking behavior performed to neutralize the
anxiety) that are time-consuming and cause distress meets
criteria for OCD. The symptoms are not solely focused on the
traumatic event, differentiating them from PTSD symptoms.
GAD would involve excessive worry about multiple events, not
ritualistic behaviors.
**Q3.** A 72-year-old man with hypertension and type 2
diabetes is brought in by his daughter for "confusion." Over the
past 18 months, he has had a progressive decline in his ability
to manage finances and medications. He recently got lost
driving to the grocery store. His MMSE score is 22/30, with
deficits in orientation, recall, and visuospatial tasks (cannot
copy intersecting pentagons). His neurological exam is notable
for mild asymmetric rigidity and a shuffling gait. He has no
tremor. Which neurocognitive disorder is most likely?
A. Alzheimer's Disease
, B. Vascular Neurocognitive Disorder
C. Neurocognitive Disorder with Lewy Bodies
D. Frontotemporal Neurocognitive Disorder
**Correct Answer: C**
**Rationale:** The key features are progressive cognitive
decline plus core features of Lewy Body Dementia: spontaneous
parkinsonism (rigidity, gait disturbance) and prominent
visuospatial deficits. The absence of tremor and the presence of
early visuospatial and attentional deficits help differentiate it
from Parkinson's Disease Dementia (which would have motor
symptoms preceding cognitive decline by a year or more).
Alzheimer's typically presents with early memory impairment;
vascular would show a stepwise decline and focal neurological
signs; FTD presents with early personality/behavior or language
changes.
**Q4.** (Select-All-That-Apply) An 8-year-old boy is referred for
evaluation of school difficulties. His teacher reports he
frequently daydreams, does not seem to listen, fails to finish
assignments, and is disorganized. His mother says he is forgetful
and loses things. He can focus for hours on video games. Which
of the following findings would be necessary to support a
diagnosis of ADHD, Predominantly Inattentive Presentation?
Select three.