Perspectives on Differential Diagnosis

(8-14-06)

Differential Diagnosis (First, Frances, & Pincus, 1995)

• Step 1: Is the presenting symptom for real?
• Step 2: Rule out substance etiology (including drugs of abuse, medication, toxin exposure.
• Step 3: Rule out a Disorder Due to a General Medical Condition.
• Step 4: Determining the specific primary disorder(s).
• Step 5: Differentiating Adjustment Disorder from Not Otherwise Specified. FFP (1995) suggest AD always has precedence (wrong)
  • Anxiety & Mood: Adjustment preempts NOS
  • Disruptive Behav. Disorder NOS vs. AD with DofC
• Step 6: Establishing the boundary with No Mental Disorder.

Differential Diagnosis of “Usually First Diagnosed in Infancy, Childhood, or Adolescence (Fauman, 1994)

• Suggests grouping into 4 groups based on predominant symptoms or deficits:
  • 1. Intellectual & cognitive impairment
  • 2. Motor Function impairment
  • 3. Disruptive or self-injurious behavior
  • 4. Information exchange

Intellectual & cognitive impairment

• MR
• LD

Motor Function impairment

• Motor Skill Disorders
• Tic Disorders
• Stereotypic Movement Disorder

Disruptive or self-injurious behavior

• ADD & Disruptive Behavior
• Feeding & Eating Disorders of Infancy or Early Childhood
• Elimination
• Separation Anxiety
• Reactive Attachment

Information exchange

• Pervasive Developmental
• Communication
• Selective Mutism

Fauman (1994) then guides differential diagnosis with four questions:

1. “Is the child’s predominant symptom an impairment of learning or intellectual functioning?”
2. “Is the child’s predominant symptom abnormal motor activity?”
3. “Is the child’s predominant symptom socially inappropriate or self-injurious behavior?”
4. “Is the child’s predominant symptom an impairment in the ability to communicate or exchange meaningful information with other people?”

Morrison’s (1995) Diagnostic Hierarchy

1. “Cognitive disorder” preempts all other diagnoses that could produce the same symptoms.” (p. 205)
2. parsimony rule: “The fewer the diagnoses, the better.” (p. 206)
3. chronology rule: “Give priority to the disorder that has been present longest.” (p. 206)
4. “If none of the foregoing rules applies, use the safety rule.” (p. 207): choose diagnoses with good outcome and response to treatment before those difficult to treat, with serious sequels, or deteriorating courses

Hierarchy of Conservative (Safe) Diagnoses (from Morrison & Munoz, 1991, p. 95)

• Most favorable (most treatable, best outcome)
  • Recurrent depression
  • Bipolar mood disorder
• Middle ground
  • Alcoholism
  • Panic disorder
  • Phobic disorder
  • Obsessive-compulsive disorder
  • Anorexia nervosa
  • Drug use
  • Borderline-personality disorder
• Least favorable
  • Schizophrenia
  • Antisocial personality disorder
  • AIDS dementia
  • Alzheimer’s dementia

Evaluation of children (House, 2002)

Begin with the presenting complaints of caretakers and begin considering high baserate problems which could account for these (Will common problem syndromes account for the present concerns?), consider if any significant clinical features are not accounted for by high baserate problems (Are additional diagnoses needed?), review low baserate problems which are easily missed (Any other problems?).

High probability problems

• academic difficulties
  • Learning Disorders
  • Mental Retardation
  • Borderline Intellectual Functioning
  • Cognitive Disorders
• behavior problems
  • ADHD
  • ODD
  • Conduct Disorder
  • Adjustment Disorder
  • Child/Adolescent Antisocial Behavior
• emotional problems
  • depression
    • Major Depression
    • Dysthymic
    • Depressive Disorder NOS
  • anxiety
    • GAD
    • Specific Phobia
    • PTSD
• substance abuse
  • Alcohol Abuse
  • drug abuse
• eating problems
  • Anorexia Nervosa
  • Bulimia Nervosa

Low probability problems

• psychosis
  • Schizophrenia
• sexual problems
• autism
  • Autistic Disorder
  • other PDD
• tic disorders
  • Tourette’s Disorder
• abuse
• TBI
• bipolar disorder