Eating disorders: Pathology review

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Case study0:00–1:19

23 year old Adeline is brought to the emergency department by her peers after fainting in the college cafeteria. Upon examination, her pulse is 47 per minute and her BP is 89/48 millimeters of mercury.
In addition, her height is 162 centimeters or 5 ft four inches and she weighs 45.4 kg or 100 lbs. Adeline mentions that she considers herself fat, which is why she's been trying to lose weight and admits to purging or making herself vomit whenever she eats a large meal.
On further questioning, she tells you that her last menstrual period was more than three months ago. You decide to run a urine pregnancy test which comes back negative.
The next day you see 17 year old Emmanuel who was brought to the clinic by his mother who saw him forcibly vomit after lunch.
Emanuel states he has recently been very anxious about the college entrance exam and that he feels like vomiting is the only thing in life that he can control his vitals show no abnormalities.
His height is 185 centimeters or 6 ft one inch and he weighs 72 kg or 158 lbs. Physical examination shows decaying enamel on teeth as well as thickened skin around the knuckles of his right hand.

Pathology1:19–1:59

Based on the initial presentation, both Adeline and Emanuel have some form of eating disorder. Eating disorders are mental disorders in which an individual exhibits abnormal eating behaviors that negatively impact their physical and mental health.
They are quite common, especially among young females who struggle with low self esteem and the social pressure to look a certain way.
However, remember that they can affect anybody regardless of their sex, age and social background for your exams. The most common eating disorders include anorexia, nervosa bulimia, nervosa binge eating disorder and pica.
Ok, let's start with anorexia, nervosa. This is characterized by a constant fear of gaining even the slightest amount of weight associated with a distorted body image with individuals often believing they are overweight while actually being underweight to be more specific, their body mass index or BMI is lower than 18.5.

Anorexia nervosa1:59–6:22

Now, there are two main types of anorexia. One is the binge eating and purging type where individuals eat large amounts of food in one sitting and then purge that food through self induced vomiting or by taking laxatives or diuretics.
And this occurs recurrently for at least three months. The other is the restricting type where people reduce the amount of food they eat or overexercise in order to lose weight without any purging.
Now, individuals affected by anorexia, nervosa literally starve themselves over time. This can result in several complications which can end up being clues to the diagnosis.
At first, there's muscle tissue loss throughout the body, which often manifests as fatigue but can also lead to difficulty breathing due to a weak diaphragm, even the heart can become weaker.
And this can manifest as bradycardia less than 60 heartbeats per minute and hypotension meaning a BP below 90/50 millimeters of mercury as well as orthostatic hypotension, which is when BP falls when a person goes from a lying down position to a standing position for those who menstruate.
Another key symptom is amenorrhea where either the normal menstrual cycle stops or menstruation doesn't start by age 15, prolonged food restriction.
As well as taking laxatives frequently can also make the gastrointestinal tract unable to handle normal meals, which can cause terrible bloating nausea and constipation.
Individuals with the binge eating and purging type might also have halitosis or really bad breath from repeated vomiting.
Also, the bone marrow can start shutting down because of the lack of essential nutrients. So you get neutropenia or fewer white blood cells, which leads to a dampened immune response, anemia or fewer red blood cells, which leads to lower energy levels.
And thrombocytopenia or fewer platelets which leads to easy bleeding and bruising anorexia can also cause osteoporosis where the bones become weak and susceptible to fractures.
The skin may also become dry, scaly and covered by brittle or soft hair called lanugo. And that's actually high yield.
Finally, it can affect the brain causing symptoms like confusion, irritability or restlessness as well as depression or anxiety.
Ultimately, individuals affected by anorexia. Nervosa may die from these complications or commit suicide.
Standard treatment of anorexia. Nervosa involves nutritional rehabilitation and psychotherapy like cognitive behavior therapy which aim at restoring and stabilizing a normal weight and eating patterns as well as changing their thoughts and beliefs about body weight and shape.
In addition, individuals with severe depression or anxiety can be treated with antidepressants such as a selective serotonin reuptake inhibitor or SSRI for short.
However, for your test, remember that the antidepressant buPROPion is contraindicated because it is associated with a higher incidence of seizures in individuals with eating disorders.
Now, what's extremely important to know for your test is that feeding an individual too rapidly or aggressively can lead to the refeeding syndrome.
That's when the sudden intake of large amounts of food causes lots of insulin to be released at once, resulting in sudden electrolyte shifts since insulin makes the cells take in potassium magnesium and phosphate.
So, lab tests will show hypokalemia, hypomagnesemia and hypophosphatemia. Keep in mind that when the serum levels of potassium fall below three millimoles per liter, it can lead to weakness, seizures, rhabdomyolysis, impaired respiratory function, cardiac arrhythmias, heart failure and even death.
So, remember that refeeding syndrome can be life threatening. Next is bulimia nervosa, which is characterized by cycles of binge eating, meaning rapid out of control, eating past the point of fullness or comfort, followed by compensatory purging to prevent weight gain, either by self induced vomiting over exercising or taking laxatives or diuretics to fit the diagnosis.

Bulimia nervosa6:22–9:13

Remember that these cycles of binging and purging must repeat consistently at least once a week for a period of three months, but sometimes can happen as often as multiple times per day.
Often the trigger for binging and purging is an emotional stressor that's not necessarily related to weight or body image.
For example, failing to reach a certain goal for your exams, you should definitely be able to distinguish bulimia from anorexia, nervosa.
So the main distinction is that individuals with bulimia usually have a BMI that's normal or high. So it's over 18.5.
Whereas individuals with anorexia typically have a BMI that's lower than 18.5. Sometimes though individuals may start with bulimia and then develop anorexia over time and vice versa.
Over time, the repeated binging and purging cycles can result in a number of serious complications. So, repeated vomiting can lead to halitosis, erosion of the dental enamel and bilateral sialadenosis, which is the swelling of the parotid glands that can make cheeks appear unusually round or puffy sialadenosis can also lead to elevated blood levels of amylase in individuals who use their hand to induce vomiting the back of the knuckles can get callused, which is called Russell's sign.
And that's an extremely high yield fact, if the vomiting is forceful enough, it can lead to tears of the distal esophagus and stomach itself, which is called mallory Weiss syndrome and can cause abdominal pain and hematemesis or vomiting blood over time.
All purging methods can cause dehydration and lead to hypotension. But unlike anorexia, that's usually combined with tachycardia or a heart rate over 100 BPM.
Purging can also cause a depletion of electrolytes, which leads to a low level of sodium chloride, magnesium phosphate and potassium as well as an excessive loss of gastric acid when vomiting leading to metabolic alkalosis treatment of bulimia.
Nervosa involves careful nutritional rehabilitation and psychotherapy to help the individual and their family structure.
A new relationship around food antidepressants can also be helpful, especially FLUoxetine, which is a selective serotonin reuptake inhibitor or SSRI I for short and again, buPROPion is contraindicated due to the risk of seizures.

Binge eating disorder9:13–10:23

Third, there's binge eating disorder, this is actually the most common eating disorder among adults. That's where individuals engage in rapid out of control binge eating at least once a week for three months.
But what's important to keep in mind is that these episodes are not followed by compensatory purging, unlike in bulimia and the binge eating and purging type of anorexia, binge eating may ultimately result in weight gain and obesity.
So, a BMI above 25 which can in turn, lead to an increased risk of complications like hypertension, coronary artery disease and type two diabetes mellitus.
Over time. These can lead to more severe and life threatening medical complications like arrhythmias and heart liver or kidney failure.
The main treatment for binge eating disorder is nutritional rehabilitation and psychotherapy. Individuals that refuse or don't respond to psychotherapy may get medical treatment with Ssris and those who don't respond to Ssris can take lisdexamfetamine to help reduce food craving and promote weight loss.

Pica10:23–12:07

Ok. The last high yield eating disorder is Pica, which is where people have strong cravings and eat bizarre non-food substances like dirt, clay, paper, raw starches, large quantities of ice or even feces for at least one month for your tests.
Keep in mind that the diagnosis shouldn't happen in the context of another eating disorder. For example, some individuals with anorexia will eat substances like paper tissues to control their appetite, but not because they crave them.
PCA is most often seen in pregnancy, Children or individuals with developmental disabilities, but it could also be associated with anemia especially from iron deficiency as well as malnutrition and emotional trauma or concomitant.
Psychiatric disorders. Complications of PCA are usually related to repeated ingestion of nonfood substances over time and include nutrition, anemia and weight changes depending on the substance consumed.
For example, weight gain with starch or weight loss with ice. In addition, some of these substances can't be digested and may cause constipation or intestinal obstruction.
Finally, some substances might be toxic and cause poisoning or contaminated and cause intestinal infections, especially parasitic.
The main treatment for PCA is nutritional rehabilitation and psychotherapy. The first step is identifying the substance craved, decreasing exposure to it and substituting a healthier alternative that will satisfy the craving.
Finally, some individuals may also benefit from medical treatment with ssris. All right, as a quick recap, anorexia is characterized by a fear of gaining weight and a distorted body image while having a BMI below 18.5.

Review12:07–12:57

There are two types, the binge eating and purging type and the restricting type bulimia is when somebody goes through cycles of binging and purging at least once a week for three months, but typically maintains a BMI above 18.5.
In binge eating disorder, individuals experience episodes of out of control eating without purging at least one a week for three months, which often results in a BMI above 25.
Finally, in Pica, individuals crave and eat nonfood substances like dirt or clay for at least a month and may result in malnutrition, anemia, constipation, poisoning or infection.
Ok. Back to our cases.
Adeline is a 23 year old girl that is brought in after an episode of fainting. This is probably related to the fact that she's showing bradycardia and hypotension.

Summary12:57–13:47

The most important clue though is that she's been trying to lose weight and considers herself fat while her BMI is 17.3 all of this combined with her amenorrhea and negative pregnancy test points to anorexia nervosa.
And because at least once in three months, she binge eats and then purges it's the binge eating and purging type. After Adeline, you see Emmanuel, a 17 year old boy who also purges through self induced vomiting.
However, unlike Adeline, he has a normal BMI of 21. This along with the decaying teeth enamel and the Russell sign around the knuckles of his right hand should immediately make you think of bulimia nervosa.
Eating disorders: Pathology Review: Video, Causes | Osmosis