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Identification of patients with diabetes

Identifying patients who have symptoms and/or signs of diabetes

  • Patients with the following symptoms and/or signs should be tested for diabetes:
    • symptoms include:
      • increased thirst
      • passing a lot of urine, especially at night
      • extreme tiredness and lethargy
      • weight loss despite increased appetite
      • genital itching or regular episodes of thrush
      • itchy skin rash or slow healing wounds
      • cystitis
      • blurred vision
      • neuropathy—”pins and needles” sensation in the legs
    • signs include:
      • persistent or recurrent infections, such as skin infections, oral or genital thrush, mouth ulcers and urinary tract infections
      • signs of microvascular complications, such as diabetic retinopathy; foot ulcers, loss of sensation in the lower limbs; or impotence
      • signs of cardiovascular disease, such as high blood pressure; manifestations of dyslipidaemia, such as xanthelasmata; absent foot pulses

Identifying asymptomatic patients with diabetes

  • The following groups of patients should be followed up and offered regular testing for diabetes:
    • people who have previously been found to have impaired glucose regulation (impaired glucose tolerance and/or impaired fasting glycaemia)
    • women who have had gestational diabetes and have tested normal following delivery – they should be tested at 1 year post-partum and then 3-yearly

Diagnosis of diabetes mellitus and impaired glucose tolerance

  • A diagnosis of diabetes must be confirmed by a glucose measurement performed in an accredited laboratory on a venous plasma sample
  • The WHO recommends that a diagnosis should never be made on the basis of glycosuria (glucose detectable in the urine) or a stick reading of a fingerprick blood glucose alone – although such tests may be useful for screening
  • As stated in WHO guidance, HbA1c can now be used as a diagnostic test for diabetes, providing that stringent quality assurance tests are in place and assays are standardised to criteria aligned to the international reference values, and there are no conditions present which preclude its accurate measurement. An HbA1c of 6.5% is recommended as the cut point for diagnosing diabetes. A value of less than 6.5% does not exclude diabetes diagnosed using glucose tests
  • In patients who have symptoms and/or signs of diabetes, a diagnosis of diabetes can be confirmed by plasma glucose levels as set on the table overleaf
  • In order to confirm a diagnosis of diabetes in people who do not have symptoms or signs of diabetes, at least two blood glucose tests must be performed on different days, the results of which must both be in the diabetic range – a diagnosis of diabetes cannot be based on a single blood glucose determination alone
  • The repeat test can either be performed on a fasting blood sample or on a random blood sample
  • If the result of the second test is not diagnostic, an oral glucose tolerance test (OGTT) should be performed
  • Some people are found to have blood glucose levels which are above the normal range but are not in the diabetic range, i.e. they have difficulty maintaining their blood glucose levels within the normal range but are able to maintain their blood glucose levels below the diabetic range
  • People with impaired glucose regulation have a greatly increased risk of developing diabetes and cardiovascular disease

Impaired glucose tolerance (IGT)

  • IGT is a stage of impaired glucose regulation and is indicative of cardiovascular risk
  • An OGTT is needed to exclude the diagnosis of diabetes

Impaired fasting glycaemia (IFG)

  • IFG classifies individuals who have fasting glucose values above the normal range but below those diagnostic of diabetes
  • All patients with IFG should have an OGTT to exclude the diagnosis of diabetes
Diagnosis of diabetes
 Glucose concentration (mmol/l)
Laboratory estimation
Fasting venous
plasma glucose
 OGTT venous
plasma glucose
 Random venous
plasma glucose
DIABETES MELLITUS ≥7.0 or ≥11.1 or ≥11.1
IMPAIRED GLUCOSE TOLERANCE (IGT) <7.0 and ≥7.8 but <11.1  
IMPAIRED FASTING GLYCAEMIA (IFG) ≥6.1 but <7.0 and <7.8  

Referral to specialist services

  • Patients with newly diagnosed diabetes should be assessed at presentation to determine whether they need to be referred to a specialist service
  • Children and young people presenting with signs and/or symptoms suggestive of diabetes should always be referred urgently on the same day by telephone to a specialist paediatric team experienced in the management of childhood diabetes (or by fax/email where fax/email referral systems are in place) for admission to hospital for initiation of insulin therapy
  • Adults who are clearly unwell, and/or who have ketones in their urine, and/or who have a blood glucose level >25.0 mmol/l, should also be referred urgently on the same day by telephone to a specialist diabetes team (or by fax/email where fax/email referral systems are in place)
  • Patients who present with diabetic ketoacidosis (DKA) or diabetic hyperosmolar non-ketotic syndrome (HONK) will require immediate treatment in hospital to correct these abnormal metabolic states
  • Refer adults <30 years old to a specialist diabetes team for – in most cases – outpatient insulin therapy; some will also require urgent specialist care
  • Newly diagnosed people with none of the above symptoms should be managed within primary care

Initial care of people with diabetes

Information and advice

  • Immediately after diagnosis, patients with diabetes should be offered an explanation of diabetes and its management on a one-to-one basis, taking into account of patient's emotional and psychological state and cultural/social background
  • Provide leaflets, audio/DVD and information about Diabetes UK and local Diabetes UK voluntary group
  • Discuss impact of the condition on everyday life
  • Advise drivers appropriately with regard to informing their insurance company and DVLA
  • Advise patients they are exempt from prescription charges for all medication (if diabetes is going to require medical treatment)


  • Treatment should be discussed with the patient and commenced as soon as appropriate
  • Initial treatment includes insulin therapy, where appropriate, and advice on diet, monitoring physical activity and giving up smoking
  • Initial treatment includes advice on diet, monitoring (if appropriate) physical activity and giving up smoking, medication if appropriate
  • All newly diagnosed people with diabetes should be referred to a registered dietitian
  • Patients with diabetes should:
    • be advised to increase their physical activity levels, adopt a healthy diet and aim to reduce their calorie intake (if overweight)
    • commence treatment with oral hypoglycaemic agents if blood glucose control is not achieved within three months
    • be considered for insulin treatment if blood glucose control is not achieved with diet, increased physical activity and combined drug therapy
    • non-insulin injection therapy may be considered where appropriate

Initial care planning and management

  • Care planning, reviewed at each appointment is at the heart of managing a person's diabetes and should include:
    • emergency contact
    • NHS and hospital numbers
    • named contact details
    • type of diabetes
    • assessment of any complications
    • information relating to blood pressure, lipids, complications, etc. and agreed self-care goals
    • psychological assessment and integrated care
  • Advice on care plans are set out in the Diabetes UK leaflet entitled Involving people with diabetes

Continuing care

  • Once their diabetes has been stabilised, patients with newly diagnosed diabetes should be invited to attend for regular reviews of their day-to-day metabolic control and ongoing education, as frequently as required to meet the needs of the individual
  • In addition, they should be recalled at least once a year for a formal review
  • Annual review:
    • exploration of any concerns, providing support and counselling as appropriate
    • assessment of ability to manage self-care
    • advice on healthy lifestyle choices
    • metabolic control:
      • HbA1c and blood glucose monitoring
      • episodes of DKA, hyperglycemic hyperosmolar state, or hypoglycaemia
      • dietary assessment
      • advice on clinical options
      • monitoring of physical growth and development (in children)
      • weight management
    • surveillance for long-term complications, such as:
      • diabetic retinopathy
      • microvascular complications
      • diabetic renal disease
      • diabetic neuropathy
      • cardiovascular risk factors
      • hyperlipidaemia
      • hypertension
      • foot problems
    • identification and management of other problems, such as depression, skin problems and sexual dysfunction
    • structured education about medication
  • Further follow-up appointments should be offered, as appropriate, to focus on any issues raised during annual review
  • Agree revised care plan and continue cycle of care

Criteria for referral to specialist services

  • Same day referrals:
    • children and young people with newly diagnosed diabetes
    • the majority of adults with newly diagnosed type 1 diabetes, particularly those who present with ketonuria or protracted vomiting
    • people with diabetes who develop infected, necrotic or gangrene or foot ulcers
    • people with diabetes who develop a suspected Charcot foot
    • all women with pre-existing diabetes (type 1 and 2) who become pregnant
    • women who develop gestational diabetes
    • people with diabetes who sustain a sudden loss of vision, pre-retinal or vitreous haemorrhage, or retinal detachment, or who develop rubeosis iridis should be referred to an ophthalmologist
  • Priority referrals:
    • women with either type 1 or type 2 diabetes who are contemplating pregnancy
    • people with diabetes who develop persistent microalbuminuria
    • people with diabetes who develop renal impairment (creatinine >150mmol/l)
    • people with diabetes who develop sight threatening retinopathy should be referred to an ophthalmologist
    • people with diabetes who develop severely at risk feet should be referred to the local diabetes foot clinic
  • People with type 2 diabetes who need to commence insulin therapy will also need to be referred to specialist services in areas where primary care services are not resourced to initiate this
  • Specialist advice may be required for people with diabetes who develop:
    • recurrent hypoglycaemia
    • poor glycaemic control
    • hypertension
    • dyslipidaemia
    • painful neuropathy which is proving difficult to treat
    • sexual dysfunction
    • amyotrophy
    • morbid obesity which requires atypical interventions, e.g. surgery such as gastric stapling
    • psychological problems, if appropriate psychological/counselling services are not available in primary care

full guidelines available from…
Diabetes UK, 10 Parkway, London NW1 7AA (Tel –020 7424 1000) and)

Diabetes UK. Recommendations for the management of diabetes in primary care 2005 World Health Organisation. Definition, diagnosis and classification of diabetes mellitus and its complications 1999.
Summary updated June 2012
First included: February 1997.