Differential Diagnosis for Unintentional Weight Loss
Single Most Likely Diagnosis
- Malnutrition secondary to Chronic Kidney Disease (CKD): The patient's low prealbumin level (16) and significant unintentional weight loss (28 lbs in 4 months) suggest malnutrition, which is common in CKD stage 4 due to poor dietary intake, inflammation, and metabolic acidosis.
Other Likely Diagnoses
- Uncontrolled Diabetes Mellitus: The patient's high HbA1c (8.8) indicates poor glucose control, which can contribute to weight loss, especially if the patient is experiencing glucosuria.
- Hypothyroidism: The elevated TSH (7.20) suggests hypothyroidism, which can cause weight loss, fatigue, and muscle weakness.
- Gastrointestinal Disorders: Conditions like gastroesophageal reflux disease (GERD), peptic ulcer disease, or gastrointestinal malignancies can cause weight loss due to decreased appetite, nausea, or malabsorption.
Do Not Miss Diagnoses
- Malignancy: Although less likely, malignancies such as pancreatic, gastric, or colon cancer can cause significant weight loss and should not be missed.
- Infections: Chronic infections like tuberculosis or endocarditis can cause weight loss and should be considered, especially in patients with CKD who are at higher risk of infections.
- Medication Side Effects: Certain medications, such as metformin or ACE inhibitors, can cause gastrointestinal side effects leading to weight loss.
Rare Diagnoses
- Amyloidosis: A rare condition characterized by the deposition of abnormal proteins in various organs, which can cause weight loss, fatigue, and renal dysfunction.
- Pheochromocytoma: A rare tumor of the adrenal gland that can cause weight loss, hypertension, and metabolic disturbances.
- Addison's Disease: A rare endocrine disorder characterized by adrenal insufficiency, which can cause weight loss, fatigue, and hypotension.