Test |
Interpretation/Action |
CRP |
>3 – Independent marker of increased risk of cardiovascular disease >10 – Indicator of chronic inflammation associated with obesity |
Fasting Glucose |
3.9 -5.5 mmol/L – Normal 5.6-6.9 mmol/L – Impaired Fasting Glucose – perform Oral Glucose Tolerance Test (OGTT) ≥7.0 mmol/L – indicates Diabetes – refer to Diabetes team for same day review For further details, see 'High HbA1c pathway for obese/overweight patients'. |
Fasting Insulin and C-Peptide |
Fasted insulin >10 mu/L (if prepubertal) or >20 mu/L (if pubertal), or fasted C-peptide >600 pmol/L suggests insulin resistance – consider starting metformin Also calculate HOMA-IR – see below |
ALT |
See section on ‘MASLD’ for further investigation of raised ALT |
HbA1c |
<39 mmol/mol – normal 39-47 mmol/mol – suggests Pre-diabetes – Perform OGTT ≥48 mmol/mol – indicates Diabetes – refer to Diabetes team for same day review For further details, see 'High HbA1c pathway for obese/overweight patients'. |
Fasting Lipid Profile |
Dyslipidaemia is indicated by fasting levels of one or more of[i]:
|
Vitamin B12 |
Included in test bundle as long-term metformin use may be associated with decreased Vitamin B12 absorption. If low consider dietary advice/ multi-vitamin, or investigation for pernicious anaemia if also anaemic |
Thyroid Function Tests |
May have slightly elevated TSH with normal/slightly elevated free T4 in the context of obesity. If TSH is raised up to twice the upper limit of normal, obtain repeat sample in ~8 weeks and if still raised discuss with Endocrinology. |
Homeostatic model assessment for insulin resistance (HOMA-IR) |
HOMA-IR = fasted insulin (µU/ml) x fasted glucose (mmol/L) / 22.5; or fasted insulin (pmol/L) x fasted glucose (mmol/L) / 135; HOMA-IR ≥4 suggests insulin resistance – perform OGTT For further details, see 'High HbA1c pathway for obese/overweight patients'. |
Gene mutation |
Features |
Melanocortin receptor 4 (MC4R) |
Most common form of monogenic obesity. Increased linear growth, hyperphagia with childhood obesity, advanced bone age |
Leptin receptor (LEPR) |
Hyperphagia, early onset obesity during infancy, immune dysfunction, central hypothyroidism, hypogonadotrophic hypogonadism |
Leptin (LEP) |
Leptin deficiency results in similar phenotype to LEPR mutations but with low leptin concentrations amenable to treatment with leptin |
Pre-opiomelanocortin (POMC) |
Present in neonatal life with adrenal crisis, pale skin, red hair, early onset obesity |
Pro-hormone convertase (PCSK1) |
Small bowel enteropathy, diarrhoea, failure to thrive during infancy followed by severe obesity in early childhood, multiple endocrinopathies (central hypothyroidism, growth hormone deficiency, hypogonadotrophic hypogonadism, diabetes insipidus) |
Single minded homolog (SIM1) |
Prader-Willi like syndrome with overlapping features including severe obesity, hypopituitarism, intellectual disability, developmental delay, behavioural problems and facial dysmorphism; however unlike PWS short stature, hypotonia and hypogonadism may be absent |
Brain derived neurotrophic factor (BDNF) |
Hyperphagia, severe obesity, hyperactivity, developmental delay |
Neurotrophic tyrosine kinase receptor type 2 (NTFK2) |
Severe obesity, impaired short-term memory, neurocognitive delay |
Syndrome |
Features |
Genetic Investigations to request |
Albright Hereditary Osteodystrophy |
Short metacarpals, rounded facies, +/- hypocalcaemia |
R293 |
Alstrom syndrome |
Retinal one-rod dystrophy, sensorineural hearing loss, dilated cardiomyopathy, hypergonadotrophic hypogonadism |
R106 |
Bardet-Biedl Syndrome |
Retinal cone-rod dystrophy, postaxial polydactyly, intellectual disability, hypogonadotropic hypogonadism, genitourinary malformations, renal malformations |
R107 |
Beckwith-Weidemann syndrome |
Overgrowth, hemihypertrophy, macroglossia, neonatal hypoglycaemia, umbilical hernia/other abdominal wall defect |
R49 |
Börjeson–Forssman–Lehmann syndrome |
Intellectual disability, seizures, hypogonadism, developmental delay, large ears |
R149 |
Carpenter syndrome |
Turricephaly (tower-shaped skull), polydactyly, syndactyly, short stature, undescended testes, intellectual disability |
R27 |
Cohen syndrome |
Failure to thrive in infancy, hypotonia, joint hypermobility, microcephaly, prominent incisors |
R149 |
Grebe syndrome |
Marked distal limb reduction, polydactyly, normal facies |
R104 |
Prader-Willi Syndrome |
Hypotonia, developmental delay, short stature, failure to thrive in infancy followed by hyperphagia and obesity, hypothalamic dysregulation (e.g. hypogonadotropic hypogonadism), sleep disordered breathing |
R48 |
ROHHAD syndrome |
Rapid onset obesity, hypothalamic dysfunction, hypoventilation, autonomic dysfunction |
- |
Temple syndrome |
Growth retardation, hypotonia, joint laxity, motor delay, early onset puberty |
R452 |
Turner syndrome |
Short female, broad chest, wide spacing of nipples, congenital lymphoedema |
Array |
WAGR Syndrome |
Wilms tumour, aniridia, genitourinary anomaly, mental retardation |
Array |
16p11.2 deletion |
Developmental delay, seizures, autism, severe obesity in early childhood, severe insulin resistance |
Array |
ALT Results |
Further Investigation required |
ALT raised up to 2x upper limit of normal (ULN) range |
|
ALT 2-3x ULN |
|
ALT >3x ULN or ALT 2-3x ULN on 2 occasions 3 months apart |
|
.. |
Cook et al (13) |
De Ferranti et al (14) |
International Diabetes Federation (15) – for ages 10-15 years (note: adult criteria if age 16+) |
Defining Criterion |
≥3 criteria |
≥3 criteria |
≥3 criteria (obesity and two risk factors) |
Obesity |
WC ≥90th percentile (age and sex specific) |
WC >75th percentile |
WC ≥90th percentile or adult cut-off if lower |
Glucose Intolerance |
Fasting glucose ≥110 mg/dL (≥6.1 mmol/L) |
Fasting glucose ≥110 mg/dL (≥6.1 mmol/L) |
Fasting glucose ≥100 mg/dL (≥5.6 mmol/L) |
Dyslipidaemia |
Triglycerides ≥110 mg/dL |
Triglycerides ≥100 mg/dL |
Triglycerides ≥150 mg/dL (≥1.7 mmol/L) |
Dyslipidaemia |
HDL-C ≤40 mg/dL (1.03 mmol/L) |
HDL-C ≤50 mg/dL (1.3 mmol/L) |
HDL-C ≤40 mg/dL (1.03 mmol/L) |
High BP |
BP ≥90th percentile (age, sex, and height specific) |
BP >90th percentile |
Systolic BP ≥130 mmHg or diastolic BP ≥85 mmHg |
. |
For children aged 1 to <13 years |
For children aged ≥13 years |
Normal BP |
Systolic and diastolic BP <90th centile for sex, age and height |
<120/<80 mmHg |
Elevated BP |
Systolic and/or diastolic BP ≥90th centile to <95th centile, or 120/80 mmHg to <95th centile (whichever is lower) |
120/<80 to 129/<80 mmHg |
Stage 1 Hypertension |
≥95th centile to <95th centile + 12 mmHg, or 130/80 to 139/89 mmHg (whichever is lower) |
130/80 to 139/89 mmHg |
Stage 2 Hypertension |
≥95th centile + 12 mmHg, or ≥140/90 mmHg (whichever is lower) |
≥140/90 mmHg |
. |
Aetiology/ Risk factors |
Situational Hypertension |
Stress, pain, anxiety |
Primary Hypertension |
More likely in children:
|
Secondary Hypertension |
More common than primary hypertension in children <6 years. Possible causes:
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History |
Physical examination |
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Personal |
Family |
Social/Environmental |
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