What is Refeeding Syndrome?

Patient Presentation
An 18-year-old female came to the emergency room with a history of restrictive eating for about 6 weeks. She had a history of anorexia nervosa that had been successfully treated with outpatient therapy and she had continued to have counseling sessions monthly while she had been living at home. She had just moved away for college and since living in the dormitory, she found that she was more anxious, concerned about her body image and was starting to fall back into her eating disordered habits. She was eating meals but was not eating as much and was choosing lower calorie items. She had increased her exercise by running 3 miles instead of 2 miles daily. She denied any purging and that had not been part of her habits before either. She had eaten a full dinner the night before and had abdominal pain afterwards. She read online about refeeding syndrome and was worried that she had it. She said that she knew she was slipping back into her old habits and wanted it to stop. She had not yet tried to find a counselor. She said her family was supportive but she wanted to “…do college on my own” and didn’t want to worry them. The review of systems showed some nausea with larger meals, no emesis or diarrhea, and no dizziness or syncope. She was taking a multivitamin.

The pertinent physical exam showed a thin female who was anxious. Her vital signs revealed 88 bpm heart rate, blood pressure of 102/66, respiratory rate of 20. Her weight was 118 pounds which was down 6 pounds from her previous weight per her history. Her physical examination was otherwise normal. The laboratory evaluation included a complete metabolic panel which was normal including calcium, magnesium and phosphorus and potassium. Her complete blood count also showed no evidence of anemia.

The diagnosis of an anxious college freshman with concerns for early relapse of anorexia nervosa was made.
The emergency room physician talked with her about local support services and followup. “All of your laboratory testing looks normal, along with your physical examination. With your symptoms I don’t think you have refeeding syndrome. I think you felt really full because your stomach isn’t used to so much food at once. Thank you for coming today. That means you really want to help yourself and we want to do that too. It can be really hard to move away from home and deal with everything on your own. But look around, adults don’t do everything on their own. We work together. Spouses, family, friends. We all help each other. Right now your usual people are far away, and they can still help, but we need to help you find some people you can trust here too. On campus, the student health center takes care of all kinds of problems and they understand how hard it can be to move away from home. They can help a lot. They can give you some short-term counseling until you can set up an appointment with someone longer-term. They will also help you find that longer-term therapist. They can also take care of any of your medical needs and the follow up you need. If it is okay with you, I can have our social worker help you to make an appointment with student health today before you leave,” the physician offered. The student agreed. By the end of the visit she stated that she was going to call her parents for additional support, and was thinking about possibly confiding in the peer resident assistant in her dorm.

Anorexia nervosa is an eating disorder with an intense fear of being overweight (i.e. distorted body image), and self-starvation and excessive weight loss. It is more common in women (1.2%) than men (0.2%) but can be seen in both genders. Risk factors include high-intelligence, perfectionism/inflexibility, anxiety, activities where thinner body types are expected (e.g. dancer, diver, gymnast, long-distance runner, volleyball player, etc.)

Other eating disorders include bulimia nervosa (i.e. cycles of binge eating and then purging), binge eating disorder (i.e. purging), orthorexia (i.e. obsessions with healthful eating), avoidant restrictive food intake disorder, compulsive exercise, laxative abuse, rumination, pica, and unspecified eating disorder. Treatment includes a multimodal approach with appropriate nutritional resuscitation (if needed) and intake, nutritional counseling, mental health counseling and support. Long-term, building skills to develop an appropriate relationship with food is the key, along with building supports to help the patient continue healthy habits.

Learning Point
Refeeding syndrome (RFS) broadly encompasses a severe electrolyte disturbance (principally low serum concentrations of the predominantly intracellular ions; phosphate, magnesium and potassium) and metabolic abnormalities in undernourished patients undergoing refeeding whether orally, enterally or parenterally. In essence, RFS reflects the change from catabolic to anabolic metabolism.”” Hypophosphatemia is considered one of the hallmarks of this process. In general there needs to be low body mass index, unintentional weight loss, minimal or no nutritional intake for a period of time (often 5-10 days) and usually electrolyte abnormalities. One of main problems is that RFS clinical features can be mild, easily overlooked and also can cause sudden morbities and even mortality. RFS prevalence varies widely depending on the group studied and the actual definition used from 0.43%-34%.

Populations at risk for RFS includes:

  • Acute or chronic disease
    • Critically ill
    • Chronic infection – HIV
    • Malignancy
    • Premature infant
    • Pregnancy
    • Prolonged emesis
    • Older age
    • Undernutrition
    • Renal failure
  • Athletes and military recruits as their nutritional intake may not match their need in training
  • Gastrointestinal problems
    • Bariatric surgery
    • Bowel resection
    • Esophageal dysmotility and dysphagia
  • Malabsorption syndrome
    • Inflammatory bowel
  • Mental health disorders
    • Alcohol and substance abuse
    • Eating disorders especially anorexia nervosa
    • Schizophrenia
  • Societal problems
    • Child maltreatment
    • Hunger strike
    • Famine
    • Migration
    • Starvation

Potential signs and symptoms of RFS include:

  • General
    • Fatigue
    • Lassitude
    • Myalgia
  • Cardiac
    • Arrhythmias
    • Congestive heart failure
    • Sudden death
  • Hematology
    • Anemia
    • Thrombocytopenia
  • Gastrointestinal
    • Constipation
    • Nausea
    • Emesis
  • Mental status changes
    • Acute encephalopathy
    • Ataxia
    • Coma
    • Delirium
    • Paresthesia
    • Peripheral neuropathy
  • Metabolic
    • Hyper or hypoglycemia
    • Hypokalemia
    • Hypophosphatemia
    • Hypomagnesemia
    • Fluid overload or dehydration
    • Vitamin and trace mineral deficiencies especially B Vitamins
  • Musculoskeletal
    • Muscle weakness
    • Osteomalacia
  • Renal
    • Acute tubular necrosis
    • Chronic renal impairment
  • Respiratory
    • Respiratory muscle weakness
    • Ventilatory dependency
    • Respiratory failure
  • Other
    • Increased risk for infections

Treatment of RFS like eating disorders requires an inpatient multimodal approach with very careful monitoring of fluid, electrolyte and energy replacement. Other nutritional supplementation is usually needed as well, along with appropriate management of the underlying cause of the RFS.

Questions for Further Discussion
1. What is female athlete triad? A review can be found here
2. What are other causes of some of the electrolyte abnormalities above such as hypophosphatemia or hypokalemia?
see Fluids and Electrolytescases here
3. What anticipatory guidance do you offer to students going off to college?
A review can be found here

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Eating Disorders and Fluid and Electrolyte Balance.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Crook MA, Refeeding syndrome: Problems with definition and management. Nutrition 2014;30:1448-1455. doi:10.1016/j.nut.2014.03.026

Silva JSV da, Seres DS, Sabino K, et al. ASPEN Consensus Recommendations for Refeeding Syndrome. Nutrition in Clinical Practice. 2020;35(2):178-195. doi:10.1002/ncp.10474

Gjoertz M, Wang J, Chatelet S, Chaubert CM, Lier F, Ambresin A-E. Nutrition Approach for Inpatients With Anorexia Nervosa: Impact of a Clinical Refeeding Guideline. Journal of Parenteral and Enteral Nutrition. 2020;44(6):1124-1139. doi:10.1002/jpen.1723

Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa