What are the potential causes of abnormal weight loss greater than 10% in an adolescent (19 years old)?

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Differential Diagnosis for Abnormal Weight Loss in a 19-Year-Old

Single Most Likely Diagnosis

  • Anorexia Nervosa: This is a common cause of significant weight loss in adolescents and young adults, characterized by a distorted body image and restrictive eating patterns. The age and magnitude of weight loss make this a highly plausible diagnosis.

Other Likely Diagnoses

  • Type 1 Diabetes: Uncontrolled diabetes can lead to significant weight loss due to the body's inability to utilize glucose, leading to the breakdown of fat for energy. Symptoms such as polyuria, polydipsia, and blurred vision may accompany weight loss.
  • Hyperthyroidism: An overactive thyroid gland can increase metabolism, leading to weight loss despite increased appetite. Other symptoms may include palpitations, tremors, and heat intolerance.
  • Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause weight loss due to malabsorption, chronic inflammation, and decreased appetite. Symptoms such as abdominal pain, diarrhea, and blood in stool may be present.
  • Depression: Severe depression can lead to loss of interest in activities, including eating, resulting in significant weight loss. Other symptoms may include persistent sadness, changes in sleep patterns, and loss of energy.

Do Not Miss Diagnoses

  • Cancer: Although less common, various types of cancer (e.g., lymphoma, leukemia, gastrointestinal cancers) can present with unexplained weight loss. Early detection is crucial for effective treatment.
  • Tuberculosis (TB): TB can cause significant weight loss, especially in immunocompromised individuals. Other symptoms may include chronic cough, fever, and night sweats.
  • HIV/AIDS: Unexplained weight loss is a common symptom of HIV/AIDS, particularly in the later stages. Other symptoms may include recurrent infections, fever, and diarrhea.

Rare Diagnoses

  • Addison's Disease: A rare endocrine disorder characterized by the insufficient production of adrenal hormones, leading to weight loss, fatigue, and changes in skin pigmentation.
  • Celiac Disease: An autoimmune disorder that causes the immune system to react to gluten, leading to malabsorption and weight loss. Other symptoms may include diarrhea, abdominal pain, and fatigue.
  • Pheochromocytoma: A rare tumor of the adrenal gland that can cause weight loss, palpitations, and hypertension due to excessive catecholamine production.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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