Archive Of Standardized Exam Questions: Diabetic Ketoacidosis (DKA)

OVERVIEW

This page is dedicated to organizing various examples of standardized exam questions whose answer is diabetic ketoacidosis (DKA). While this may seem a odd practice, it is useful to see multiple examples of how DKA will be characterized on standardized exams (namely the boards and the shelf exams). This page is not meant to be used as a tradition question bank (as all of the answers will be the same), however seeing the classic “test” characterization for a disease is quite valuable.

KEY CHARACTERISTICS OF THIS CONDITION (ON EXAMS)

When it comes to standardized exams, each topic has its own “code” marked by key buzzwords, lab findings, clues, etc. If you are well versed in this code you will be able to more quickly identify the condition that is being discussed, and get the right answer on the exam you are taking. Below is the “code” for DKA

Chief Complaints:

  • Confusion/altered mental status
  • Nausea/vomiting
  • Abdominal pain 
  • Weakness/fatigue

Patient History:

  • Diagnosis of diabetes: generally more common in type 1 diabetes
  • Symptoms suggestive of diabetes: urinary frequency and thirst can hint at a diagnosis of type 1 diabetes.

Clinical Workup:

  • Fruity odor on breath is a very specific clue
  • Rapid breathing : Kussmaul respirations are “classically” seen
  • Diffuse abdominal tenderness: especially to deep palpation
  • Elevated blood sugar: will be reported
  • Decreased blood pH: patients will have acidemia
  • Ketones in urine/serum: required for the real-life diagnosis
  • Hyperkalemia will also be present in patients (due to lack of insulin driving it into cells).
QUESTION EXAMPLES

Question # 1

A 10 year old girl is brought to the hospital because she has fatigue, difficulty breathing, and has also been having many episodes of vomiting today. Her skin is flushed, warm, and she appears to be volume depleted. There is a fruity odor noted when smelling her breath. She is in the 80th percentile for height, and the 25th percentile for weight. Her temperature  99.2°F, pulse is 115/min, respirations are 25/min, and blood pressure is 100/55 mm Hg. Her capillary refill time is 5 seconds and her blood glucose is 510 mg/dL. What is the likely diagnosis in this patient?

Explanation: fruity odor on breath + high blood sugar = DKA

Explanation # 1

fruity odor on breath + high blood sugar = DKA

Question # 2

A 5 year old boy has severe fatigue, no appetite, and has also lost 7 lbs in the past few months. He appears lethargic, and is having difficulty concentrating. His pulse is 80/min and blood pressure is 75/45 mm Hg. His serum glucose concentration is measured and is 510 mg/dL. A urinalysis shows 3+ ketones, 4+ glucose. What is the likely diagnosis in this patient?

Explanation # 2

High blood sugar + glucose in urine + ketones in urine = DKA

Question # 3

A 30 year old woman suffers from frequent urination, blurred vision, and rapid breathing for the past 1 day. Her use is 115/min, respirations are 27/min, and her blood pressure is 100/55 mm Hg. A physical exam is non-contributory. Lab studies are shown below:

  • Sodium: 140 mEq/L
  • Chloride: 100 mEq/L
  • Potassium: 4.6 mEq/L
  • Bicarbonate: 18 mEq/L
  • Glucose: 803 mg/dL***
  • Urine ketones: positive***

What is the likely diagnosis in this patient?

Explanation # 3

High blood sugar + ketones in urine = DKA

Question # 4

A 15 year old female is brought to the ED because she has a 4 hour history of being confused and disoriented. She states that her stomach hurts and that she would like water. She has vomited once in the last 2 hours. Her past medical history is notable for type 1 diabetes and she regularly takes insulin. Her symptoms gradually began overnight after she stayed up at friends house during a sleep over where she ate a lot of junk food. Currently her pulse is 115 ppm, respiration’s are 25/min. and blood pressure 100/70 mm Hg. Her breaths are rapid and deep. Lab studies are conducted and reveal a serum glucose concentration of 450 mg/dL, and a arterial blood pH of 7.15. What is the likely diagnosis in this patient?

Explanation # 4

Confused/disoriented patient + type 1 diabetes + rapid/deep breaths + increased serum glucose + acidemia = DKA

Question # 5

A 34 year old female is brought to the hospital because she has a 5 hour history of nausea and vomiting. She was diagnosed with type 1 diabetes as a teenager. She currently is confused and sleepy. Her blood pressure is 85/60 mm Hg, heart rate is 120 ppm, and her respirations are 28/min. Labs are collected and show a blood glucose of 850 mg/dL, a BUN of 40 mg/dL, and a arterial pH of 7.18. What is the likely diagnosis in this patient?

Explanation # 5

Confused/disoriented patient + type 1 diabetes + rapidbreaths + increased serum glucose + acidemia = DKA

Question # 6

A 25 year old female comes to the doctor because she has abdominal pain. She also has been experiencing nausea and lost appetite for the past few days. An abdominal exam reveals diffuse tenderness . Labs are collected and are shown below:

  • Serum sodium: 133 mEq/L
  • Serum chloride: 100 mEq/L
  • Serum potassium: 6.1 mEq/L***
  • Serum bicarbonate: 11 mEq/L
  • Serum glucose: 475 mg/dL***

What is the likely diagnosis in this patient?

Explanation # 6

Abdominal pain (generalized) + nausea + hyperkalemia + increased glucose = DKA

Question # 7

A 15 year old male is brought to the clinic because he has been experiencing shortness of breath over the past 2 days that has been occurring with little exertion. He has has been suffering from nausea, weakness, and fatigue. He explains that for the past 2 weeks he has had urinary frequency and excessive this. The patient has a heart rate of 95 bpm, blood pressure is 100/65 mm Hg in the office. His respirations are 35/min. A physical exam is otherwise non-contributory. Labs are collected and are shown below.

  • Serum sodium: 130 mEq/L
  • Serum chloride: 85 mEq/L
  • Serum potassium: 6.0 mEq/L
  • Serum glucose: 496 mg/dL***
  • Serum ketones: positive ***

What is the likely diagnosis in this patient?

Explanation # 7

Nausea/weakness/fatigue + rapid breathing + increased glucose + serum ketones = DKA

TESTABLE FACTS ABOUT THIS TOPIC (BEYOND ITS IDENTIFICATION)

Many questions on standardized exams go beyond simply recognizing the underlying topic. Often there are specific testable facts regarding some aspect of the topic’s pathophysiology/management/clinical implications that are commonly asked. Some of these are listed below:

 EXPECTEE LABS:
  • Serum CO2: will be decreased because rapid breathing will result in increased loss of CO2
  • Bicarbonate: will be decreased because ketone acids will consume
  • Anion gap: increased due to ketone acids
  • Hyperkalemia: due to lack of insulin driving it into cells
TREATMENT:
  • Fluids: to rehydrate patients and help with blood pressure
  • Insulin: to lower blood sugar
  • Potassium: insulin will shift potassium into cells, so it needs to be given to make sure patients don’t become hypokalemic.

 

 

 

Page Updated: 11.18.2016