Latent auto immune diabetes of adulthood (LADA)

LADA has an auto-immune aetiology like T1DM but tends to present later in life than classical T1DM and often runs a more indolent course, with a slow insidious onset. Indeed some authorities only recognise LADA as a variant of T1DM. Historically, also known as 'type one and a half diabetes'.

FBC

Baseline haematological and biochemical investigations are mandatory in all newly presenting cases of diabetes.

Serum B12 and red cell folate

Pernicious anaemia may accompany LADA as an auto-immune phenomena.

U and Es

Patients with DKA may develop hyperkalaemia, dehydration and renal impairment. Assessment of urea and creatinine is also essential to gauge baseline renal function in any newly diagnosed case of diabetes.

LFTs

Baseline haematological and biochemical investigations are mandatory in all newly presenting cases of diabetes.

Bone profile

Baseline haematological and biochemical investigations are mandatory in all newly presenting cases of diabetes.

Plasma glucose

In most symptomatic cases the degree of hyperglycaemia will be such that there is no doubt about the diagnosis.

However, in borderline cases WHO criteria for diagnosis should be applied. These are that a fasting plasma glucose >7 mmol/L, or a random plasma glucose >11.1 mmol/L on one occasion in symptomatic patients or on two occasions in asymptomatic patients, indicates a diagnosis of diabetes mellitus.

If these criteria are not met it may be necessary to perform a 75 g oral glucose tolerance test. The same biochemical cut offs are used for the fasting and two hour values. 

All patients who are acutely unwell with diabetes must have a formal laboratory glucose assay.

Cortisol level

Many centres will not routinely assess cortisol at presentation but in any patient with diabetes who subsequently becomes unwell with frequent hypoglycaemia, unexplained weight loss and abdominal pains, lethargy or other vague constitutional symptoms, a random cortisol may be a useful test.

If it is greater than 550 nmol/L then no further action is needed. But, if not, it may be appropriate to proceed to a short synacthen test.

TFTs

Hypothyroidism is routinely screened for at diagnosis, in many centres, as an auto-immune association of LADA.

Thyroid auto-antibody screen

Some centres routinely screen for thyroid auto-antibodies at diagnosis as an auto-immune associate of auto-immune diabetes.

Coeliac screen

Coeliac diasease is routinely screened for as an auto-immune association of LADA.

ECG

Not normally necessary but may be performed if there is suspicion of pre-exisitng ischaemic heart disease.

Fasting lipids

These are an important baseline but are often elevated before insulin therapy has been commenced.

HbA1c

This is often performed at diagnosis but in actual fact contributes very little at this stage as it will almost invariably be elevated.

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