Differential Diagnosis I
Latent autoimmune diabetes in adults (LADA)– A slow-developing autoimmune diabetes, similar to type I and type II diabetes, that occurs when there is a loss of self‐tolerance against endocrine pancreas β cells, leaving the pancreas unable to produce sufficient insulin, eliminating the ability to regulate the metabolic process that provides cells with energy (Yohena et al., 2019).
Figure 6. What is insulin? (Hormone Health Network, 2019)
Rationale:
Symptoms of LADA have clinical characteristics that are similar to both types I and type II diabetes. Patients with LADA are often misdiagnosed with type II diabetes due to their similarities (Yohena et al., 2019). Although the symptoms can be vague at first, the patient will develop symptoms similar to those in our patient, including polydipsia, polyuria, nocturia, paresthesias, and insulin resistance that is increased due to obesity. LADA is also more common in patients whose age is >35.
Clinical findings not associated with DM
- Patients with LADA typically have lower BMIs
- The patient is experiencing weight gain
- Providers have no record of the patient testing positive for autoantibodies.
- No familiarity of autoimmune disease
- The patient has had no history of DM, making it difficult to consider LADA as the primary diagnosis. Lada patients are usually diagnosed after an ineffective treatment with oral medications is documented.
Differential Diagnosis II
Diabetes insipidus (DI)- An insufficiency of antidiuretic hormone that leads to polyuria and polydipsia. The inability to concentrate urine, and the excretion of large volumes of dilute urine, can result in severe dehydration (McCance & Huether, 2019).
Figure 7. Diabetes Insipidus, Central (Cook Children’s, 2019)
Rationale:
The patient presented to the emergency department complaining of polydipsia, polyuria, and nocturia. These are hallmark signs of DI. The patient also stated that he has some weakness, and his wife reported changes in his mental status. Electrolyte imbalances can result from the body’s inability to replace the water that is lost as a result of polyuria, which can cause weakness and confusion (McCance & Huether, 2019).
Lab findings not associated with DI:
- Hemoglobin A1c was high at 10% (DI does not elevate blood glucose).
- Urine specific gravity (SG) was normal (DI can result in SG dropping below 1.010).
- The basal metabolic panel was normal (DI can cause hypernatremia; sodium >145 mEq/L)
Past medical history:
The patient does not report any history of polycystic kidney disease, pituitary disorders, hypothalamic injury, hypercalcemia, head tumors, or sickle cell disease; therefore, he has no common risk factors associated with the development of DI (Kalra et al., 2016).
Differential Diagnosis III
Metabolic syndrome- A cluster of disorders that increase the risk of developing DM and cardiovascular complications that includes central obesity, dyslipidemia, prehypertension, and elevated fasting blood glucose (McCance & Huether, 2019).
Rationale:
Diagnosis of metabolic syndrome requires any three of the following criteria:
- A waist circumference that is >40 inches in men or >35 inches in women ✔️
- Elevated plasma triglycerides of ≥150 mg/dL
- Plasma high-density lipoprotein cholesterol <40 mg/dL in men or <50 mg/dL in women
- An elevated blood pressure that is ≥130/85 mmHg
- Impaired fasting glucose level ≥100 mg/dL ✔️
(McCance & Huether, 2019)
Diagnosis criteria review:
The patient presented with two of the five traits necessary for a diagnosis of metabolic syndrome, including obesity with increased waist circumference and an elevated fasting blood glucose. While the patient may not meet the criteria for a diagnosis of metabolic syndrome, having just one of these traits significantly increases his risk of heart disease and DM. As more of these conditions develop, the risk will continue to climb.
Figure 8. Metabolic Syndrome: Toxicology’s Next Patient (Communiqué, 2017)