Glucose Intolerance Clinical Presentation

Updated: Jul 08, 2020
  • Author: Samuel T Olatunbosun, MD, FACP, FACE; Chief Editor: George T Griffing, MD  more...
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There are varying and similar presentations between patients with type 1 diabetes mellitus, type 2 diabetes mellitus, gestational diabetes, prediabetes, and glucose intolerance.

Type 1 diabetes mellitus

The warning symptoms of type 1 diabetes include polyuria, polydipsia, and polyphagia due to hyperglycemia. Patients may present with the unexplained weight loss and easy fatigability that result from reduced glucose use and increased catabolism.

Irritability, drowsiness, and loss of consciousness may occur, especially as ketoacidosis develops. The temporal profile is consequent to progression of the metabolic derangement, which is characterized by dehydration, electrolyte abnormalities, osmolality, and acid-base disturbances. After presentation with ketoacidosis, a patient may briefly revert to normoglycemia without requiring therapy (ie, the honeymoon remission).

Type 2 diabetes mellitus

Patients with type 2 diabetes may have any of the symptoms described under type 1 diabetes, but often these persons are asymptomatic. Hyperosmolar nonketotic coma, which may complicate type 2 diabetes mellitus, is characterized by severe dehydration secondary to osmotic diuresis from hyperglycemia. Ketoacidosis, although uncommon, may also occur in type 2 diabetes.

For more information, see Hyperosmolar Coma.

Antecedent history in patients with type 2 diabetes includes frequent or recurrent infections, poor wound healing, blurring of vision, and numbness or tingling sensations in the extremities.

Gestational diabetes mellitus

Gestational diabetes is typically detected during routine screening of pregnant women for glucose intolerance. Any degree of glucose intolerance with onset or recognition during gestation places a patient in the category of gestational diabetes mellitus. [38, 39, 40]


The categories of impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) have been officially termed prediabetes, because they are risk factors for future diabetes and for cardiovascular disease. [41, 42]  However, the World Health Organization (WHO) recommends the term intermediate hyperglycemia, noting that prediabetes does not  always progress to diabetes as the term implies and the focus on diabetes may divert attention from the significantly increased cardiovascular risk. [3]  

Most cases of IGT and IFG are diagnosed when the presence of one or more cardiovascular risk factors necessitates the need to screen for a disorder of glucose tolerance.

Patients with impaired glucose homeostasis are generally asymptomatic. Features of related risk factors for cardiovascular disease may be present, even with a mild degree of hyperglycemia. They include a history of hypertension, obesity, dyslipidemia, and/or macrovascular disease, such as stroke, coronary disease, or peripheral vascular disease.

Glucose intolerance

Diagnosis of glucose intolerance may coincide with various patient conditions that may be complicated by glucose intolerance, such as liver cirrhosis, end-stage renal disease, and some rare genetic disorders.


Physical Examination

Overt hyperglycemia that has progressed to diabetes, if left untreated, may result in signs of dehydration. Hypotension and other features of hemodynamic decompensation occur with worsening hyperglycemia. Other clinical features, such as Kussmaul respiration and altered level of consciousness due to metabolic derangement, are commonly observed during acute deterioration. Evidence of a precipitating factor, such as fever from an infectious process, may be present and should always be sought.

In routine evaluation of patients with glucose intolerance, weight, height, waist, and hip measurements are recommended. The aim is to determine the body mass index (BMI), the risk level, and the presence of truncal obesity. In type 2 diabetes, 60-90% of patients are obese. A patient may have central adiposity in spite of a normal BMI. Skin-fold thickness measurement may also be useful in determining regional fat distribution, although it is not often accurate or reproducible.

Peripheral stigmata of lipid abnormalities and atherosclerosis, such as premature arcus cornealis, xanthelasma, eruptive (skin) xanthomata, tendon xanthomata, and lipemia retinalis, may be found in some patients.

Blood pressure measurement is important, because hypertension is a frequent component of the dysmetabolic syndrome. Hypertension is 1.5 to 2 times more common in individuals with diabetes than in matched individuals without diabetes. Approximately 40% of individuals with hypertension have impaired glucose tolerance.

A thorough evaluation of the various systems and organs is pertinent. An eye examination is important; ocular manifestations, such as pupillary abnormalities, cataract, refractory errors, retinopathy, and other changes, may be found in patients with diabetes. These manifestations result mainly from chronic, uncontrolled hyperglycemia.

A neurologic examination is also necessary, because muscle wasting, sensory abnormalities, and other features of neuropathy are characteristic of many patients with diabetes who have chronic complications.

Related diseases

Specific phenotypic characteristics are found in certain conditions, especially the genetic syndromes.

In addition to glucose intolerance, patients with type A insulin resistance (absent or dysfunctional insulin receptor) may have certain clinical features such as (1) acanthosis nigricans, which is hyperpigmentation and skin thickening of flexural areas, or (2) features of hyperandrogenism, some variants of which may be characterized by thin or muscular body habitus or acral enlargement (pseudoacromegaly).

Due to autoantibodies to the insulin receptor, this resistance commonly manifests as symptomatic diabetes mellitus; ketoacidosis is unusual. Other genetic syndromes associated with insulin resistance include leprechaunism (abnormal facies, growth retardation) and lipodystrophic states (diverse phenotypic manifestations).

Other patients may have physical findings that are characteristic of certain internal organ diseases, in which glucose intolerance is only part of the spectrum of metabolic derangement that complicates these conditions. In cirrhosis, the liver may be normal, enlarged, or shrunken, depending on the disease stage. Other clinical features of portal hypertension and liver cell failure are often present. In cases of uremia, the various systemic changes, with the wide range of external manifestations that occur in the late phases of renal failure, are generally evident.