Differential Diagnosis for Loss of Appetite

The differential diagnosis for loss of appetite is broad and can be categorized into several groups based on the likelihood and potential impact of the condition.

• Single Most Likely Diagnosis

  • Depression: This is often one of the most common causes of loss of appetite. Depression can lead to a decrease in interest in activities, including eating, and can be associated with significant weight loss if not addressed.
  • Anxiety: Similar to depression, anxiety can suppress appetite, leading to reduced food intake.

• Other Likely Diagnoses

  • Gastroesophageal Reflux Disease (GERD): Symptoms of GERD, such as heartburn and dysphagia, can make eating uncomfortable, leading to a decrease in appetite.
  • Peptic Ulcer Disease: The pain associated with peptic ulcers can deter individuals from eating, especially if the pain is exacerbated by food intake.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause abdominal pain, diarrhea, and other symptoms that may reduce appetite.
  • Chronic Kidney Disease: Uremia associated with kidney failure can lead to a decrease in appetite among other symptoms.
  • Chronic Liver Disease: Liver dysfunction can cause a range of symptoms including nausea, vomiting, and abdominal discomfort, all of which can lead to a decrease in appetite.

• Do Not Miss Diagnoses

  • Cancer: Various types of cancer, especially those affecting the gastrointestinal tract, can lead to a significant loss of appetite. Early detection is crucial for effective treatment.
  • HIV/AIDS: Infection with HIV can lead to a range of symptoms including weight loss and loss of appetite, particularly in the later stages of the disease.
  • Tuberculosis: This infectious disease can cause significant weight loss, fever, and loss of appetite, among other symptoms.
  • Addison's Disease: This rare endocrine disorder can lead to weight loss, loss of appetite, and other systemic symptoms due to adrenal insufficiency.

• Rare Diagnoses

  • Amyotrophic Lateral Sclerosis (ALS): While primarily a motor neuron disease, ALS can lead to difficulties in eating and swallowing, indirectly affecting appetite.
  • Dementia: Certain forms of dementia can lead to changes in eating habits and loss of appetite due to cognitive decline.
  • Prion Diseases (e.g., Creutzfeldt-Jakob Disease): These rare neurodegenerative disorders can cause a range of symptoms including changes in appetite.
  • Mitochondrial Disorders: These are a group of disorders caused by dysfunctional mitochondria and can lead to a wide range of systemic symptoms, including loss of appetite.