**4. Epidemiology of DKA**

There is wide geographic variation in the frequency of DKA at onset of diabetes; rates inver‐ sely correlate with the regional incidence of type 1 diabetes. Frequencies range from 15 to 70% in different regions of the world [9 -14].

#### **4.1. Frequency of DKA**

At disease onset

**2. Definition of Diabetic Ketoacidosis (DKA)**

*The biochemical criteria for DKA include the following triad [4]:* **•** Hyperglycemia (blood glucose >11 mmol/L [200 mg/dL])

Diabetic ketoacidosis (DKA) results from absolute or relative deficiency of circulating insu‐ lin and the combined effects of increased levels of the counterregulatory hormones: cate‐

**•** undiagnosed type 1 diabetes mellitus (T1DM); DKA is reported be the first presentation

**•** patients on treatment who miss their insulin doses, especially the long-acting component of a basal-bolus regimen. It is estimated that 75% of DKA episodes are associated with in‐

*Relative insulin deficiency*, on the other hand, occurs when the concentrations of counterregu‐

The combination of low serum insulin and high counterregulatory hormone concentrations results in an accelerated catabolic state with increased glucose production by the liver and kidney (via glycogenolysis and gluconeogenesis), impaired peripheral glucose utilization re‐ sulting in hyperglycemia and hyperosmolality, and increased lipolysis and ketogenesis,

Hyperglycemia and hyperketonemia cause osmotic diuresis, dehydration, and electrolyte loss. This stimulates stress hormone production, which induces insulin resistance and leads to a vicious circle, worsening the hyperglycemia and hyperketonemia. Fatal dehydration and metabolic acidosis will ensue if management is not initiated. Poor tissue perfusion or

sepsis may lead to lactic acidosis which can aggravate the ketoacidosis [5].

**•** Venous pH <7.3 and/or bicarbonate <15 mmol/L

cholamines, glucagon, cortisol and growth hormone [5].

*Absolute insulin deficiency* occurs in the following conditions:

**•** patients who use insulin pump if insulin delivery fails [7].

**•** gastrointestinal illness with diarrhea and vomiting.

causing ketonemia and metabolic acidosis [4].

latory hormones increase in response to stress in conditions such as:

in about 25% of cases especially in those less than 5 years old [ 2 ].

**•** Ketonemia and ketonuria

294 Type 1 Diabetes

**3. Pathophysiology of DKA**

sulin omission or treatment error [6].

**•** sepsis,

**•** trauma, or

DKA at diagnosis of type 1 diabetes occurs more commonly in [15,16]:


Type 2 diabetes mellitus (T2DM), associated with increased rates and severity of obesity, may account for as much as one half of newly diagnosed diabetes in those aged 10 to 21 years, depending on the socioeconomic and ethnic composition of the population [2]. Acute decompensation with DKA has been recognized to occur at the time of diagnosis in as many as 25% of children with type 2Diabetes Mellitus (T2DM0 [17].

*In children with established diabetes (recurrent DKA)[4]*

The risk of DKA in established T1DM is 1–10% per patient per year

Risk is increased in the following conditions [18 ]:

