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Personality disorders: Pathology review



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Psychological disorders review

Personality disorders: Pathology review


0 / 14 complete

USMLE® Step 1 style questions USMLE

14 questions

A 29-year-old woman comes to the office for a routine check-up at the prompting of her parent. The patient’s parent reports that the patient has endured emotional abuse by her partner. The patient refuses to end the relationship with her partner and feels uneasy when the partner is not around. She adds, “I'm worried that if I leave the relationship, my life will only get worse.” She has not been employed since she started dating and living with her partner, and she is convinced that nobody would hire her. A review of her medical record indicates that she has endured several episodes of verbal abuse from prior relationships, which she suggested “were all her fault.” She has had four prior serious relationships and reports that she has not been single for more than a few weeks in the last 10 years. The patient’s parent states that they manage most of her finances and that the patient is “unable to handle it on her own.” She does not have any friends outside of her romantic relationship. Vitals are within normal limits. Physical examination is unremarkable. Which of the following best describes the underlying cause of this patient’s behavior?  


Content Reviewers:

Antonella Melani, MD

28 year old Anna is brought to the emergency department by her roommate, who found her in the bathroom about to cut her wrists. Anna tells you that her boyfriend of two weeks broke up with her today. When asked how she feels, she just utters “empty”.

She also discloses that she’s been in several intimate relationships that are always amazing in the beginning, but they all end up being disappointing. Upon physical examination, you notice that Anna has multiple scars over her forearms and wrists.

Next, 35 year old Luis presents to the clinic with his girlfriend, who thinks that he is too shy and he would benefit from getting professional help.

Luis mentions that since childhood, he’s always been the “silent” one. He has very few friends, and he avoids hanging out with new people, since he is afraid they will not like him.

Finally, you see Bella, a 41 year old woman, who comes to the emergency department because she thinks she’s been poisoned by her fiancé. She is certain that he’s been planning to kill her before they get married.

When you ask her why she suspects this or if she has any proof, Bella says that her fiancé has frequently offered to prepare her meals.

She also mentions that she’s afraid she’ll lose her job, because her coworkers have been trying to sabotage her. In addition, Bella doesn’t talk to any of her relatives, because four years ago they forgot her birthday.

Okay, based on the initial presentation, Anna, Luis, and Bella all seem to have a personality disorder.

Now, each of us has a set of personal traits, which are repetitive patterns involving the way we think, feel, act or behave, and perceive ourselves and what surrounds us.

This combined is what makes up a person’s personality. Despite that, we should normally be able to cope with daily circumstances and adapt our personality accordingly.

Now, sometimes these personal traits can interfere with someone’s day-to-day functioning in their personal life, at work, or in social settings. If this were the case, we would say that the individual has a personality disorder.

Generally, personality disorders are characterized by personality traits that can be rigidly pervasive, meaning that they are stable and of long duration, inflexible, meaning that individuals act in a certain way in most situations, and maladaptive, meaning that they have a hard time adjusting to new or different circumstances.

However, what’s high yield is that these traits remain ego-syntonic, meaning that they stay consistent with the individuals’ values, beliefs, and self-image, also known as ego.

And sometimes, this keeps individuals affected by a personality disorder from viewing their behaviors as problematic.

Now, for your exams, you need to know that personality disorders typically arise in adolescence or early adulthood, and there are ten personality disorders that are classified into clusters A, B, and C, each with its own specific patterns of thought and behaviors.

All right, so cluster A personality disorders are characterized by odd or eccentric thinking or behavior, and include paranoid personality disorder, schizoid personality disorder, and schizotypal personality disorder.

What’s extremely high yield for your exams is that cluster A personality disorders are linked to higher rates of schizophrenia, and vice versa, individuals that have a genetic association with schizophrenia are more likely to develop a cluster A personality disorder.

Okay, starting with paranoid personality disorder, this describes someone who is accusatory or generally distrustful and suspicious of other people without really having any reason or proof.

They also assume that others will disappoint them, manipulate them, or talk about them behind their back. Because of this, they are constantly hypervigilant or excessively alert, and are quick to get angry and counterattack or hold grudges.

And that’s a high yield fact! In many ways, this behavior can totally affect the individual’s work, social life and the way they relate to those around them, creating a cycle that leads to even more paranoid behaviors, and ultimately, to social withdrawal or awkward behaviors. So, remember that these people tend to have superficial relationships.

Next there’s schizoid personality disorder. That’s where individuals avoid social interaction because they simply aren’t interested in getting to know others.

In a test question, look for someone who lacks close friends and almost always chooses solitary activities because they don’t enjoy company.

These people even have anhedonia, meaning that they enjoy few, if any activities, and don’t find pleasure in physical contact, from sexual activity to holding hands.

Another important thing to keep in mind is that these individuals tend to have a flat affect and emotional blunting, meaning that they don’t show positive or negative emotions.

The last cluster A personality disorder is schizotypal personality disorder, which is where an individual comes across as being quirky or eccentric.

People with schizotypal personality disorder can be overly superstitious or might engage in excessive magical thinking, like believing in clairvoyance or telepathy.

Related to this would be ideas of reference, which are the false belief that real and irrelevant occurrences or details directly relate to oneself.

Like thinking that it’s raining because the world is sending them a specific signal. Make sure not to confuse these with delusions, which are beliefs that are not based in reality.

And that’s important because it can help you set schizotypal personality disorder apart from schizophrenia, where delusions are characteristically present!

Now, like those with schizoid personality disorder, individuals with schizotypal personality disorder tend to be socially awkward and have few close people.

Unlike schizoid, though, they usually have a strong desire to have them, but are often unable to maintain them. That’s because these people have a self-centered way of speaking, dressing or acting that is socially inappropriate and can turn people off.

A way to remember this is that those with schizoid are distant with a “D”, and those with schizotypal have odd thoughts with a “T”.

Finally, another thing to keep in mind is that individuals with schizotypal personality disorder have an inappropriate or constricted affect, which might cause them to laugh at a funeral or smile at the news of a tragedy.

Okay, let’s switch gears and discuss cluster B personality disorders, which are characterized by overly emotional, dramatic or unpredictable thinking or behavior and include antisocial personality disorder, borderline personality disorder, histrionic personality disorder, and narcissistic personality disorder.

For your exams, keep in mind that all four of these have a genetic association with mood disorders like depression and bipolar disorder, as well as substance misuse.

All right, let’s start with antisocial personality disorder. This sounds like individuals don’t get along well with others, but don’t let this confuse you. In fact, it’s the opposite, they can be really charming, and often use that to manipulate others for their personal gain.

For your exams, remember that individuals with antisocial personality disorder show little empathy, meaning they are unwilling to recognize the feelings and needs of others, as well as a lack of remorse or guilt, as shown by the indifference when hurting, mistreating, or stealing from others. They also disregard moral values and societal norms, and have poor impulse control.

This combination makes them willing to hurt others if it helps them, lie repeatedly and use aliases, making them prone to aggressive and unlawful behavior, at times earning the label sociopath or psychopath. For your test, remember that individuals with this disorder tend to be overrepresented in prison populations.

Another unique thing about antisocial personality disorder is that it’s most common in males, and to meet the diagnosis, individuals must be over 18 years old and have a history of conduct disorder with onset before age 15.

So if the individual is under the age of 18, the diagnosis is conduct disorder instead. And that’s a high yield fact! Next up is borderline personality disorder, which instead is more common in females. Now, individuals with borderline personality disorder tend to have unstable moods.

So, they can go from being happy one minute to rage or sadness the next; this leads to a pattern of intense and unstable relationships, which alternate between extremes of idealization and disappointment.

For example, one might think his or her partner is the love of their lives, and the next day think that the same person is totally worthless.

Remember that this pattern is sometimes called stable instability because the only consistent thing is instability. And it can cause people with a borderline personality disorder to feel "empty" and "lost".

What’s high yield here is that these people often use a defense mechanism called splitting where people and important things, like a job, are seen as either completely good or completely bad.

In addition, people with borderline personality disorder are often terrified of abandonment and might even do extreme things, including suicidal behavior, threats, or self-mutilating behavior like deliberately cutting or burning themselves.

This can be associated with a lack of impulse control, which may lead to potentially self-damaging behavior like spending money they don’t have or abusing certain substances.

Next, there’s histrionic personality disorder, where the key features are excessive emotionality, meaning that emotions are labile or rapidly shifting and shallow, as well as attention-seeking.

In fact, individuals are uncomfortable in situations where they’re not the center of attention, and often manipulate situations to draw more attention to themselves.

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