Hurry up!
: : Get The Offer
Unlimited Access Step ( one, two and three ).
Priority Access To New Features.
Free Lifetime Updates Facility.
Dedicated Support.
1
Question:

A 23-year-old woman comes to the emergency department due to right wrist pain after a fall.  The patient fell on her outstretched hand while walking across the floor at a gym where she exercises regularly.  She has no significant medical history and takes no medications.  The patient says she avoids eating high-fat or high-carbohydrate foods because she wants to avoid "getting bloated" and "gaining fat."  Her last menstrual period was 7 months ago.  She does not use tobacco, alcohol, or recreational drugs.  Temperature is 35.9 C (96.6 F), blood pressure is 90/58 mm Hg, and pulse is 48/min.  BMI is 18 kg/m2.  Tenderness and swelling are present over the right distal radius.  The parotid glands are enlarged and there are fine, soft hairs on her extremities.  Urine pregnancy test is negative.  X-ray reveals a nondisplaced fracture of the right distal radius and generalized radiolucency of the bone.  Which of the following is the most likely underlying diagnosis?

Hurry up!
: : Get The Offer
Unlimited Access Step ( one, two and three ).
Priority Access To New Features.
Free Lifetime Updates Facility.
Dedicated Support.


Explanation:

There are many explanatory sources, such as pictures, videos, and audio clips to explain these explanations and questions and explain the answers, but you must subscribe first so that you can enjoy all these advantages. We have many subscription plans at the lowest prices. Don't miss today's offer. Subscribe

Anorexia nervosa

Epidemiology

  • Increased risk in white individuals, industrialized countries, athletes, models
  • Median onset at age 18
  • 10:1 female/male ratio

DSM-5 diagnostic criteria

  • Restricted energy intake with significantly low body weight (BMI generally <18.5 kg/m2)
  • Intense fear of becoming fat or persistent avoidance of weight gain
  • Distorted body image, excessive influence of weight on self-worth, or persistent denial of complications related to low body weight

Medical
complications

  • Osteoporosis
  • Amenorrhea
  • Lanugo or hair loss
  • Parotid hypertrophy (if binge/purge behavior)
  • Hypotension, hypothermia, bradycardia
  • Cardiac atrophy, arrhythmias

This patient has a restricted diet, thin body habitus, and amenorrhea (last menstrual cycle 7 months ago); these features suggest functional hypothalamic amenorrhea (FHA), characterized by a low-estrogen state due to suppression of GnRH by chronic energy deficits.  Hypoestrogenism in FHA increases the risk for osteoporosis, suggested by this patient's low-trauma fragility fracture (eg, fall from standing height).

FHA is a potential manifestation of anorexia nervosa (AN), an eating disorder that should be suspected in patients with the following:

  • Low BMI (<18.5 kg/m2)
  • Restrictive eating patterns or purging behaviors (eg, self-induced vomiting leading to parotid hypertrophy)
  • Physiologic changes arising from chronic caloric deficits and associated clinical starvation (eg, bradycardia, osteoporosis, lanugo [ie, fine, downy body hair])
  • Distorted body image and abnormal fear of gaining weight

Like AN, bulimia nervosa is characterized by abnormal fear of gaining weight; however, the predominant behavior pattern includes cycles of binge eating with purging (eg, vomiting, laxative abuse), and BMI is generally normal or near-normal.  Electrolyte disorders are common, but manifestations of clinical starvation, seen in this patient (eg, FHA, lanugo, osteoporosis), are inconsistent with bulimia nervosa (Choice C).

(Choice B)  Avoidant/restrictive food intake disorder is characterized by inadequate food intake due to lack of interest in eating (eg, dislike of sensory experience of eating).  Patients may have low BMI and signs of nutritional deficiency, but fear of gaining fat and distorted body image are not seen.

(Choices D and E)  Celiac disease and hyperthyroidism can cause weight loss and osteoporosis.  However, the patient's fear of gaining fat suggests an alternate diagnosis; moreover, parotid gland swelling, bradycardia, and hypothermia are not expected in either of these conditions.

Educational objective:
Anorexia nervosa is characterized by low body weight (BMI<18.5 kg/m2), fear of becoming fat, and distorted body image.  Unlike other patterns of restrictive eating (eg, bulimia nervosa), patients with anorexia nervosa experience complications of progressive clinical starvation, such as bradycardia, osteoporosis, and amenorrhea.