Differential Diagnosis for Metabolic Acidosis
Single Most Likely Diagnosis
- Diabetic Ketoacidosis (DKA): Given the patient's history of diabetes, obesity, and chronic kidney disease, DKA is a highly plausible cause of metabolic acidosis. The recent stroke could also contribute to stress-induced hyperglycemia, increasing the risk of DKA.
Other Likely Diagnoses
- Lactic Acidosis: This could be due to tissue hypoperfusion, possibly related to the recent stroke, sleep apnea, or deconditioning. The patient's chronic kidney disease could also impair lactate clearance.
- Chronic Kidney Disease (CKD)-related Acidosis: The patient's GFR of 34 indicates significant renal impairment, which can lead to a failure to excrete hydrogen ions, resulting in metabolic acidosis.
- Medication-induced Acidosis: Certain medications, such as metformin (commonly used in diabetes management), can cause lactic acidosis, especially in patients with renal impairment.
Do Not Miss Diagnoses
- Salicylate Toxicity: Although less common, salicylate toxicity can cause metabolic acidosis and is often seen in elderly patients who may be taking aspirin for various reasons, including stroke prevention. Missing this diagnosis could be fatal.
- Ethylene Glycol or Methanol Poisoning: These toxicities can cause severe metabolic acidosis and are critical to identify promptly due to their high mortality rate if left untreated.
- Sepsis: Elderly patients, especially those with recent stroke and chronic conditions, are at increased risk of sepsis, which can lead to metabolic acidosis. Early recognition is crucial for survival.
Rare Diagnoses
- Type 1 Diabetes: Although less common in elderly patients, new-onset type 1 diabetes can occur at any age and could present with DKA.
- Alcoholic Ketoacidosis: If the patient has a history of alcohol abuse, this could be a rare but possible cause of metabolic acidosis.
- Renal Tubular Acidosis (RTA): Certain types of RTA can cause metabolic acidosis, but they are less common and typically have specific underlying causes or associated conditions.