Normoglycemic diabetic ketoacidosis (NDKA) is a serious metabolic state where the body produces high levels of blood acids called ketones, leading to acidosis. Unlike traditional diabetic ketoacidosis (DKA), NDKA occurs without extremely high blood sugar levels. Because blood glucose can appear normal or only slightly elevated, the condition presents a diagnostic challenge and can be overlooked, potentially delaying medical care.
Underlying Causes of Normoglycemic DKA
A primary cause for the increasing incidence of NDKA is a class of medications known as SGLT2 inhibitors, such as canagliflozin, dapagliflozin, and empagliflozin. These drugs prompt the kidneys to excrete excess glucose through urine. This action lowers blood sugar but can create a carbohydrate deficiency, shifting the body’s metabolism toward fat breakdown and ketone production, even while blood glucose readings remain normal.
This metabolic shift is not caused solely by medication. Other triggers include prolonged fasting or very low-carbohydrate diets, which can deplete available glucose and force the body to rely on fat for energy, increasing ketone production. This is particularly relevant for individuals with type 1 diabetes.
Acute physical stressors like severe illnesses, infections, major trauma, or surgery can also trigger NDKA. These events elevate stress hormones that work against insulin, promoting fat breakdown and ketone production. Excessive alcohol consumption is another cause, as it can disrupt the liver’s glucose production and favor ketone creation.
Recognizing the Symptoms
The symptoms of NDKA are nearly identical to those of traditional DKA, stemming from high ketone levels and acidosis. Individuals may experience significant nausea, vomiting, and abdominal pain. A general feeling of profound fatigue and lethargy is also common as the metabolic imbalance worsens.
A sign of advancing ketoacidosis is a change in breathing. A person may begin to breathe very deeply and rapidly, a pattern known as Kussmaul breathing, as the body attempts to expel carbon dioxide and reduce blood acidity. Another characteristic symptom is a fruity or acetone-like odor on the breath, caused by the exhalation of ketones.
The deceptive nature of NDKA is that classic high blood sugar symptoms are absent. Unlike typical DKA, NDKA does not cause extreme thirst or frequent urination. This lack of familiar warning signs can mislead individuals, making it important to recognize the other symptoms of ketoacidosis to seek timely help.
Diagnosis and Medical Intervention
Diagnosing NDKA requires looking beyond a simple blood sugar test, as glucose readings are often normal or only slightly high. Confirmation relies on laboratory tests that measure the components of ketoacidosis. The primary diagnostic tool is a blood test for beta-hydroxybutyrate, the main ketone body, though high ketone levels can also be detected in urine.
In addition to ketone levels, clinicians use an arterial blood gas test to confirm metabolic acidosis. This test measures blood pH and bicarbonate levels. In NDKA, the blood pH will be low (less than 7.3) and bicarbonate levels will be depleted (less than 18 mEq/L).
Treatment is administered in a hospital and follows a protocol to correct dehydration and halt ketone production. The first step is administering intravenous (IV) fluids to restore hydration. Following this, an IV insulin drip is started to switch off the body’s ketone production by signaling cells to use glucose for energy.
A component of NDKA treatment is the concurrent administration of IV dextrose, a form of sugar. While this may seem counterintuitive, it provides the body with a glucose source. This allows the insulin to clear ketones without causing blood sugar to drop to dangerously low levels (hypoglycemia).
Prevention and Risk Management
For individuals at risk, especially those taking SGLT2 inhibitors, proactive management helps prevent NDKA. Patients should discuss a plan with their doctor for sick days or before scheduled surgery. This plan often involves temporarily stopping the SGLT2 inhibitor to reduce risk during times of physical stress.
High-risk individuals can benefit from home monitoring and following general “sick day rules” for early detection. Important practices include:
- Having ketone testing supplies, such as blood or urine strips, available at home
- Staying well-hydrated
- Trying to consume some carbohydrates, even if appetite is low
- Monitoring both blood sugar and ketone levels frequently when feeling unwell
Seek immediate medical attention if symptoms of DKA, such as nausea, vomiting, or abdominal pain, appear. This is true regardless of the reading on a blood glucose meter, as NDKA presents without the warning sign of high blood sugar.