AANP Family Nurse Practitioner (FNP) Certification ExamDiagnosisMedium
A 48-year-old male presents with a 2-week history of nocturnal polyuria (waking up multiple times to urinate), polydipsia (excessive thirst), and fatigue. He reports a 10-pound unintentional weight loss over the same period. His body mass index (BMI) is 32 kg/m². Random blood glucose is 280 mg/dL (normal < 200 mg/dL). What is the most likely diagnosis?
- ADiabetes Insipidus
- BType 2 Diabetes Mellitus
- CUrinary Tract Infection (UTI)
- DType 1 Diabetes Mellitus
Show answer & explanationAnswer & explanation
Correct answer: B. Type 2 Diabetes Mellitus
The patient's age (48), obesity (BMI 32), classic symptoms of polyuria, polydipsia, fatigue, and unintentional weight loss, combined with a significantly elevated random blood glucose, are all highly suggestive of new-onset Type 2 Diabetes Mellitus.
Why the other options are wrong
- A. Diabetes Insipidus involves polyuria and polydipsia but is due to a deficiency in ADH or renal unresponsiveness to ADH, leading to dilute urine and normal blood glucose levels.
- C. A UTI would cause dysuria, frequency, urgency, and sometimes fever, but typically not significant polydipsia, weight loss, or such a high blood glucose level.
- D. Type 1 DM typically presents in younger, non-obese individuals with more acute and severe symptoms, often with ketoacidosis. His age and BMI make Type 2 more likely.
Type 2 Diabetes Mellitus (T2DM)
A chronic metabolic disorder characterized by insulin resistance and relative insulin deficiency, leading to hyperglycemia. It often develops in middle-aged or older adults, frequently associated with obesity.
- Symptoms include polyuria, polydipsia, fatigue, and unintentional weight loss.
- Risk factors include obesity, family history, and physical inactivity.
- Diagnosis confirmed by elevated blood glucose levels (fasting, random, or A1C).
Memory trick: Diabet-2-es: 'Too Much' sugar, 'Too Much' thirst, 'Too Much' pee.