Suspected Diabetes in Children Algorithm

Safety

Red Flags — exclude diabetic ketoacidosis and act on new-onset diabetes today

Done

New-onset type 1 diabetes in a child is a medical emergency in evolution. Some present in DKA — which is life-threatening but preventable; delayed diagnosis or treatment can cause severe morbidity and death. Recognise it, measure a glucose, and escalate.

Suspected DKA Vomiting, abdominal pain, dehydration, Kussmaul (deep sighing) breathing, acetone/pear-drop breath, drowsiness or confusion + hyperglycaemia/significant ketones → Immediate hospital transfer (999 if shocked, reduced consciousness, severe dehydration, Kussmaul breathing, repeated vomiting, airway concern or rapidly deteriorating)

Reduced consciousness / shock Floppy, very drowsy, signs of shock (cool peripheries, prolonged cap refill, tachycardia) → 999

Symptomatic + hyperglycaemia Osmotic symptoms + raised capillary glucose (a triage test; plasma glucose > 11 mmol/L in the symptomatic context indicates diabetes) → Same-day paediatric diabetes referral — do not wait for fasting or HbA1c

Infant / very young child Suspected type 1 diabetes needs same-day referral at any age; young age increases concern because presentation is non-specific and deterioration can be rapid. Diabetes before 6 months → consider neonatal monogenic diabetes (same-day specialist assessment); 6–12 months may still be type 1 → Same-day specialist

Significant ketones Blood β-hydroxybutyrate ≥ 3 mmol/L, or urine ketones ≥ ++, with hyperglycaemia → strongly concerning for DKA → Immediate hospital assessment for blood gas and electrolytes (DKA also requires acidosis — pH < 7.3 or bicarbonate < 15 mmol/L); 999 if clinically unstable

"Unwell with ketones" Vomiting, abdominal pain, hyperventilation, dehydration, drowsiness or reduced consciousness in a child with hyperglycaemia or significant ketones → Immediate transfer to hospital with acute paediatric facilities — never manage in the surgery or send home to await an appointment

Known diabetes + normal glucose Euglycaemic DKA is particularly relevant in children with known diabetes (insulin omission, illness) — suspect DKA with vomiting, abdominal pain, hyperventilation, dehydration or reduced consciousness even if glucose is normal → Immediate hospital assessment. Without known diabetes, normal glucose + ketones may be starvation ketosis, but the clinical condition determines urgency.

A substantial proportion of children with new type 1 diabetes in the UK still present in DKA, and the proportion is highest in the under-5s, where symptoms are most easily mistaken for gastroenteritis or a urinary tract infection. DKA at diagnosis is associated with cerebral oedema (the main cause of diabetes death in children) and with worse long-term glycaemic control. Earlier recognition — before vomiting and acidosis develop — is the single most effective way to prevent these outcomes.

NICE NG18 is explicit: refer children and young people with suspected type 1 diabetes immediately, on the same day, to a multidisciplinary paediatric diabetes team for confirmation of diagnosis and immediate care. A capillary blood glucose performed in the consultation is all that is needed to act — never default to an outpatient fasting test, which risks the child deteriorating into DKA while waiting.

Diagnose

Recognise the presentation — the "4 T's" and osmotic symptoms

Done

Most children present with a short history (days to a few weeks) of osmotic symptoms. Keep a low threshold — symptoms are easily attributed to a viral illness, UTI, or behaviour.

Toilet (polyuria)

Passing more urine, getting up at night to wee, or secondary enuresis — a previously dry child who starts bedwetting again. Heavy/soaked nappies in an infant.

Thirsty (polydipsia)

Drinking much more than usual, craving sugary drinks, carrying a water bottle everywhere, drinking from taps.

Tired

Lethargy, irritability, falling asleep, drop in school performance or activity.

Thinner (weight loss)

Unintentional weight loss or failure to gain weight despite a good or increased appetite. Plot on the growth chart.

Other clues

Recurrent or persistent genital/oral thrush, recurrent skin infections, blurred vision, abdominal pain, low mood/behaviour change, and the smell of acetone (pear drops) on the breath.

Don't be reassured by

A "normal" appetite, a child who looks well, or a recent viral illness — these do not exclude diabetes. The combination of thirst + weight loss + polyuria is diabetes until proven otherwise.

The Diabetes UK "4 T's" campaign (Toilet, Thirsty, Tired, Thinner) was designed precisely because childhood diabetes is frequently missed at first contact — children are often seen one or more times before diagnosis, and a proportion are only diagnosed once they present acutely unwell in DKA. Holding the 4 T's in mind during any consultation with a thirsty or tired child, or one with new bedwetting, shortens the time to diagnosis.

Secondary nocturnal enuresis (a child who was reliably dry and starts wetting the bed again) is a classic and under-recognised presenting feature. New bedwetting plus thirst should always prompt a finger-prick glucose rather than a continence referral.

Diagnose

Point-of-care testing — identify hyperglycaemia and check ketones now (triage, not diagnosis)

Done

Capillary blood glucose

Do this first, in the room A finger-prick glucose takes seconds. In a child with osmotic symptoms, a raised capillary glucose (e.g. > 11 mmol/L) strongly supports diabetes and requires same-day specialist referral. Capillary glucose is a triage test, not a substitute for laboratory plasma glucose confirmation — do not delay referral to arrange confirmatory testing. A single normal capillary reading does not exclude early diabetes if symptoms persist.

Blood or urine ketones

Always pair with the glucose Blood-ketone meter preferred (capillary β-hydroxybutyrate). ≥ 3 mmol/L, or urine ketones ≥ ++, with hyperglycaemia is strongly concerning for DKA → immediate hospital assessment for blood gas, electrolytes and specialist treatment (999 if clinically unstable). It does not by itself establish DKA — acidosis must also be assessed. Urine ketones are less preferred when a blood-ketone meter is available.

Urine dipstick

Glycosuria supports the diagnosis (and helps where a meter is unavailable). Absence of glycosuria does not exclude diabetes, particularly early; urine glucose is affected by renal threshold variation and does not replace blood glucose testing. Also screens for ketones and for a coincidental UTI. Glycosuria + symptoms = same-day referral.

Diagnostic glucose thresholds

NICE NG18: plasma glucose > 11 mmol/L in a symptomatic child indicates diabetes; confirmation (laboratory plasma glucose) and classification are by the paediatric diabetes team. DKA is diagnosed by acidosis (venous/capillary pH < 7.3 or bicarbonate < 15 mmol/L) with ketonaemia (β-hydroxybutyrate > 3 mmol/L or urine ketones ++ or above); most children also have plasma glucose > 11 mmol/L, but in known diabetes DKA can occur with a normal glucose — acid–base status is confirmed in hospital. Do not delay same-day referral to obtain HbA1c or an OGTT; they are not required before referral in a symptomatic child.

Hydration & obs

Assess hydration, capillary refill, pulse, blood pressure, respiratory rate/pattern, conscious level (AVPU), and weight/recent growth trajectory where feasible — do not delay transfer for testing. Tachypnoea/Kussmaul breathing or drowsiness shifts you to the DKA pathway.

What NOT to do

Do not send the child away for a fasting venous glucose, HbA1c, or OGTT and review later. Do not initiate insulin or metformin in routine general practice unless working within an established specialist paediatric diabetes protocol with direct specialist instruction. Same-day specialist confirmation.

In an asymptomatic person, diagnosis requires two abnormal results. But in a child with classic osmotic symptoms, a plasma glucose > 11 mmol/L indicates diabetes (a capillary result is the triage step; the specialist team confirms) — and, importantly, is at imminent risk of DKA. The pragmatic primary-care action is therefore: measure a finger-prick glucose, and if raised in a symptomatic child, refer the same day without waiting to repeat or confirm with HbA1c.

Pairing every glucose with a ketone measurement is what separates "new diabetes for same-day clinic review" from "DKA needing emergency admission". A blood-ketone meter gives an immediate β-hydroxybutyrate level; ≥ 3 mmol/L with hyperglycaemia indicates significant ketosis — strongly concerning for DKA — and the child needs immediate hospital assessment, where acidosis is checked.

Diagnose

Type 1 vs Type 2 vs monogenic — but do not let typing delay referral

Done

Assume type 1 in any child or young person with new diabetes unless there is strong evidence otherwise — type 1 is by far the most common and is the type that can deteriorate quickly. Classification is confirmed by the specialist team.

Type 1 (default)

Most children. Short history, marked weight loss, ketosis-prone, often lean, no strong family history of T2. Any age including infancy. Treat every new paediatric diabetic as T1 for referral urgency.

Type 2 — consider if

Overweight/obese, older child/adolescent, acanthosis nigricans, strong family history of T2, higher-risk ethnicity (South Asian, Black, Middle Eastern), features of PCOS. Type 2 in young people can also present with ketosis or DKA — do not downgrade urgency or delay same-day assessment because the child is overweight or has acanthosis nigricans.

Monogenic (MODY)

Consider with a family history across generations (suggestive, not diagnostic), mild stable hyperglycaemia (interpreted over time), or diabetes diagnosed < 6 months of age (neonatal monogenic diabetes — same-day specialist assessment); diabetes at 6–12 months may still be type 1, but consider monogenic diabetes in appropriate contexts. Genetic testing is specialist-led. Suspected diabetes of any type still needs same-day paediatric diabetes-team assessment.

Secondary / other

Diabetes with cystic fibrosis, pancreatic disease, steroid therapy, or syndromic associations. Context usually obvious — still needs specialist input.

Why it can wait

The acute risk (DKA) is the same whatever the type. Antibody and C-peptide testing to confirm T1 vs T2 are done by the specialist team — never delay the same-day referral to "type" the diabetes in primary care.

Type 2 diabetes is increasingly seen in adolescents, particularly with obesity and in higher-risk ethnic groups, and acanthosis nigricans (velvety hyperpigmentation in the neck and axillae) is a useful bedside marker of insulin resistance. However, adolescents with type 2 can still present with marked hyperglycaemia and ketosis, so the safe default in any acutely symptomatic young person is to manage as type 1 until the specialist team confirms otherwise.

Diabetes diagnosed in the first 6 months of life is very rarely autoimmune type 1 — it is usually monogenic (neonatal) diabetes, where genetic testing can identify children who may be treated with sulfonylureas rather than insulin. This is one reason every infant with diabetes needs same-day specialist referral rather than empirical primary-care management.

Diagnose

Mimics & differentials — consider, but glycosuria/hyperglycaemia means diabetes

Done

Urinary tract infection

Frequency, dysuria, secondary enuresis — can mimic polyuria. Dip the urine: nitrites/leucocytes suggest UTI, but glycosuria points to diabetes. The two can coexist; a raised glucose still needs referral.

Diabetes insipidus

Polyuria + polydipsia with dilute urine and a normal glucose. No glycosuria/ketones. Suspect if intense thirst but glucose normal. Persistent polyuria/polydipsia with a normal glucose → repeat assessment, urine testing, serum electrolytes and paediatric advice. DI with dehydration or hypernatraemia is an urgent hospital problem, not a routine endocrinology referral.

Primary (habitual) polydipsia

Excessive drinking driving polyuria; normal glucose, normal/dilute urine. Diagnosis of exclusion once diabetes and DI are ruled out.

Hypercalcaemia / hyperthyroidism

Can cause polyuria, thirst, weight loss and behaviour change. Consider if glucose normal and clinical picture fits; check the relevant bloods.

Gastroenteritis

The classic DKA misdiagnosis — vomiting + abdominal pain + lethargy. A child with "gastroenteritis" who is also thirsty, polyuric or has heavy ketones needs a glucose checked before being sent home.

Eating / behaviour

Weight loss with normal glucose may have other causes (coeliac, eating disorder, hyperthyroidism, malignancy) — but exclude diabetes first with a finger-prick.

The most dangerous mimic is gastroenteritis: a child with early DKA has nausea, vomiting and abdominal pain, and may be labelled with a viral illness and sent home. The discriminating step is trivial — a capillary glucose and ketones. Any vomiting child who is also thirsty, passing lots of urine, breathing deeply, or has ketones must have diabetes actively excluded before discharge.

Diabetes insipidus and primary polydipsia both cause thirst and polyuria but with a normal blood glucose and no glycosuria or ketones. They are far less common and far less acutely dangerous than diabetes mellitus, so the sequence is always: exclude diabetes mellitus first (finger-prick glucose + urine dip), then consider these rarer causes if the glucose is normal.

Refer

Referral Criteria

Done

Emergency admission (999 if unstable)

Suspected DKA: hyperglycaemia + significant ketones (blood ≥ 3 mmol/L / urine ≥ ++) with vomiting, abdominal pain, hyperventilation, dehydration or altered consciousness; shock; reduced consciousness; inability to maintain oral intake; rapidly deteriorating child → immediate transfer to a hospital with acute paediatric facilities. 999 for shock, reduced consciousness, severe dehydration, Kussmaul breathing, repeated vomiting, airway concern or rapid deterioration.

Same-day paediatric diabetes team

NICE NG18 / QS125: refer any child/young person with suspected new diabetes (assume type 1 unless strong evidence otherwise) on the same day for confirmation and immediate care — even if well and not ketotic, and regardless of age or body habitus (polyuria/polydipsia with weight loss or tiredness and hyperglycaemia; symptomatic hyperglycaemia; glycosuria with compatible symptoms). Phone the on-call paediatric/diabetes team; do not refer by routine letter.

Young children

Same-day referral applies to suspected type 1 diabetes at any age; young age increases concern (non-specific presentation, rapid deterioration) but is not a separate rule. Diabetes before 6 months → consider neonatal monogenic diabetes — same-day specialist assessment, regardless of how well they look.

Same-day specialist (type 2 / atypical)

Overweight adolescent with hyperglycaemia but no ketosis, or suspected MODY/monogenic — still refer the same day to the paediatric diabetes team (NICE QS125: suspected diabetes of any type is referred and seen the same day); typing is a specialist task. Do not downgrade urgency because of body habitus.

Endocrinology (non-diabetes)

Polyuria/polydipsia with a normal glucose and no glycosuria → consider diabetes insipidus/primary polydipsia: repeat assessment, urine testing, serum electrolytes and paediatric advice; DI with dehydration or hypernatraemia → urgent hospital assessment.

How to refer well

State the capillary glucose and ketone values, hydration/conscious level, symptom duration, and weight trend. Make verbal contact so the team can stream the child to ward or clinic and start education immediately. Use the current local paediatric diabetes service contact details and local escalation pathway.

NICE NG18 sets the standard that suspected type 1 diabetes is referred the same day to a specialist paediatric diabetes team — this is non-negotiable and applies even to the well-looking child, because insulin deficiency can tip into ketoacidosis within hours. Same-day specialist involvement also allows immediate structured education for the child and family, which improves long-term outcomes and reduces re-admission.

There is no NG12-style suspected cancer pathway for childhood diabetes — it is not a malignancy. The analogous time-critical action here is the same-day paediatric diabetes referral. (If a child instead has unexplained petechiae, hepatosplenomegaly, or persistent unexplained bone pain, that is the separate NG12 "very urgent FBC + immediate paediatric referral" leukaemia pathway — see the paediatric cancer referral algorithm.)

Treat

Initial management — what to do and what not to do in primary care

Done

Well child, no ketosis

Same-day referral + keep hydrated do not start insulin

Arrange same-day specialist review. Keep the child hydrated (oral fluids if alert and not vomiting); the receiving team advises on appropriate fluids. Safety-net for vomiting/drowsiness. The team starts insulin and education.

Suspected DKA

Emergency transfer

Arrange emergency transfer to a hospital with acute paediatric facilities. ABC assessment, monitoring, and oxygen only if clinically indicated. Obtain glucose and ketones if this does not delay transfer; IV access only if trained and it does not delay transfer. Do not give a large fluid bolus unless the child is clinically shocked and this is directed by an appropriate senior paediatric/prehospital team (risk of cerebral oedema). Nil by mouth is not universal — an alert, non-vomiting child may take small sips unless the receiving team advises otherwise. DKA management is hospital-based (BSPED guideline).

Type 2 / atypical

Refer — do not start metformin

Confirmation, antibody/C-peptide testing and treatment choice are specialist decisions. Lifestyle advice can begin, but drug therapy is initiated by the team.

Do NOT

Do not arrange a fasting glucose, HbA1c or OGTT and review later in a symptomatic child. Do not start insulin or metformin (unless within an established specialist protocol with direct specialist instruction). Do not delay referral to obtain antibody/C-peptide results, urine culture or other investigations. Do not diagnose DKA from glucose and ketones alone — acidosis needs hospital assessment.

Fluids

Keep the child hydrated — allow oral fluids if alert and not vomiting. Sugar-free fluids are not mandatory; the receiving team should advise on appropriate fluids, especially if glucose is not markedly raised or oral intake is poor. In suspected DKA, fluids are managed in hospital — avoid aggressive pre-hospital boluses unless shocked.

Communication

Explain to the family that this is likely diabetes and needs hospital today; pre-warn them admission is likely for type 1. Provide the team's contact and clear return advice.

Document

Record glucose and ketone values with the time, hydration and conscious level, who you spoke to, and the agreed plan/destination.

Next steps: see Type 1 diabetes · DKA

Insulin initiation, fluid management and the structured education that a newly diagnosed family needs are all specialist functions delivered by the paediatric diabetes team, often during a short admission. The primary-care job at diagnosis is recognition, point-of-care testing, DKA screening, and getting the child to the right place the same day — not starting treatment.

In suspected DKA, over-rapid or large-volume fluid resuscitation is associated with cerebral oedema, the leading cause of death in paediatric DKA. Unless the child is frankly shocked, pre-hospital and primary-care fluid boluses should be cautious and guided by the receiving paediatric team, who follow the BSPED DKA guideline (with ISPAD, international).

Lifestyle

Family support & the ongoing primary-care role

Done

Diagnosis-day support A new diagnosis is frightening. Be calm and clear: diabetes is serious but very manageable, the hospital team will teach them everything, and the child can live a full life. Signpost Diabetes UK and Breakthrough T1D (formerly JDRF) for family resources.

Know the 4 T's as a practice Toilet, Thirsty, Tired, Thinner. Brief reception and clinical staff so a thirsty, tired child losing weight gets a same-day appointment and a finger-prick glucose, not a routine slot.

Sick-day rules (once established) Sick-day rules are specialist-provided — reinforce, don't rewrite, the team's written plan. Children should not stop basal insulin during illness unless instructed by the diabetes team; monitor glucose and ketones more often, maintain fluids/carbs, and seek help early. Insulin adjustment, diabetes technology and ketone-management plans remain with the paediatric diabetes team.

School & activity Support the Individual Healthcare Plan, hypoglycaemia awareness for staff, and full participation in sport and school trips. Children with diabetes should do everything their peers do.

Immunisations Keep routine childhood immunisations up to date, and offer the annual influenza vaccine; pneumococcal and other vaccinations per the current UKHSA Green Book and specialist immunisation guidance (not automatically identical for all children with diabetes).

Whole-family healthy habits Balanced eating, limiting sugary drinks, and being active benefit the whole family and are especially relevant where type 2 risk factors (obesity, family history) are present.

Although specialist teams lead diabetes care, the GP remains central — for acute illness, mental-health support, contraception and transition in adolescence, immunisations, and for keeping the whole practice alert to the 4 T's so the next child is diagnosed sooner. Embedding the 4 T's in triage is a simple, high-impact safety intervention.

Children and young people with diabetes are recommended to receive the annual influenza vaccine, with pneumococcal vaccination as indicated by the current UKHSA Green Book, because intercurrent infection both worsens glycaemic control and precipitates DKA. Keeping immunisations current is a tangible, GP-deliverable way to reduce admissions.

Safety

Safety-Netting & Follow-up

Done

Child awaiting same-day review

While arranging specialist assessment, send to ED immediately if vomiting, abdominal pain, deep or rapid breathing, worsening lethargy or drowsiness, dehydration, inability to drink, rising glucose or ketones, confusion or reduced consciousness. Do not advise repeated home glucose checks as an alternative to same-day assessment when symptoms and hyperglycaemia are already present.

"Glucose borderline / symptoms ongoing"

If the finger-prick is normal but symptoms persist, do not simply reassure — repeat the assessment, dip the urine, consider serum electrolytes, and discuss with paediatrics (DI with dehydration or hypernatraemia is an urgent hospital problem). Early diabetes can have intermittent readings.

Attend ED / 999 if:

Repeated vomiting, tummy pain, fast or "sighing" breathing, breath smells of pear drops, very drowsy/floppy, unable to keep fluids down, signs of dehydration, rising glucose or ketones, or confusion (999 if collapsed, very drowsy or deteriorating rapidly).

Same-day review if:

New or increasing thirst/urination, ongoing weight loss, new bedwetting, or a parent who remains worried — bring the child back for a glucose check rather than waiting.

Established diabetes (GP role)

Support attendance at specialist clinic and structured education; immunisations per the current Green Book (annual flu; pneumococcal as indicated); reinforce (not rewrite) the specialist sick-day rules — basal insulin is not stopped during illness unless the diabetes team instructs; insulin adjustment, technology and ketone plans stay with the paediatric diabetes team. Ensure safeguarding and mental-health support, and be alert to eating difficulties, insulin omission, recurrent DKA and diabetes distress.

Documentation

Record the glucose/ketone values and time, the conscious level/hydration, the type/urgency of referral, who was contacted, and the safety-net advice given to the family.

Specific, action-oriented safety-netting saves lives in suspected diabetes: families need to know exactly which symptoms (vomiting, deep breathing, drowsiness, pear-drop breath) mean "go straight to A&E", not just "come back if worried". This is most important in the window between a primary-care suspicion and the child being seen by the specialist team.

A single normal finger-prick does not exclude evolving diabetes if symptoms are convincing — glucose can fluctuate early in the disease. The safe approach is active review (repeat testing, urine dip, paediatric discussion) rather than discharge, because the cost of a missed diagnosis is DKA.