Anorexia nervosa
BioMG follows French guidelines. Adapt it to the guidelines and the tests available where you practise.
Anorexia nervosa
Fasting laboratory tests
- FBC
- Serum electrolytes
- Serum calcium
- Serum phosphate
- 25-hydroxyvitamin D
- Serum creatinine with eGFR
- Urea
- AST
- ALT
- Alkaline phosphatase
- PT
- Serum albumin
- Prealbumin
- CRP
- TSH (clinical doubt); TSH, free T4, free T3 if onset before age 13if neededAdult: only if diagnostic doubt in favour of hyperthyroidism persists [2]. Anorexia starting before age 13: TSH, free T4 and free T3 are part of the specialist tests of the PNDS [3].
- Plasma glucose (child, early-onset anorexia)if neededAnorexia nervosa starting before age 13: plasma glucose is part of the standard first-line tests of the PNDS [3].
- aPTT (child, early-onset anorexia)if neededAnorexia nervosa starting before age 13: the PNDS adds aPTT to PT in the standard tests; if prolonged, measure the vitamin K-dependent factors [3].
- Serum magnesium (if severe undernutrition or purging behaviours)if needednon-French guidelineThe American Psychiatric Association (2023) and an American Family Physician review count magnesium among the electrolytes to check, and the German association BFE measures it from the outset [4,5,6]; the British MEED report links hypomagnesaemia to laxative abuse and an increased risk of arrhythmia [7]. The HAS (2010) does not list it in these tests and cites it only among the criteria for hospitalisation of children and adolescents [2].
- IgA anti-tissue transglutaminase antibodies (tTG-IgA) (if digestive symptoms, iron or folate deficiency)if needednon-French guidelineThe British MEED report asks for coeliac disease to be looked for as soon as there is doubt (functional digestive disorders, weight loss, iron or folate deficiency), without delaying refeeding [7]; the American Family Physician cites it among the tests to request on indication [5]. The HAS (2010) does not mention it [2]; before age 13, the PNDS places this test in the specialist tests [3].
Anorexia nervosa: severity and start of refeeding
At the start of refeeding for severe undernutrition, to be repeated according to progress
- Serum electrolytes (serum potassium, serum sodium)
- Serum phosphate
- Serum magnesium
- Plasma glucoseif neededMalaise, signs of hypoglycaemia: symptomatic hypoglycaemia (< 0.6 g/L) or asymptomatic (< 0.3 g/L) in adults is a criterion for hospitalisation [2].
- Urine dipstick: ketonuria in a child or adolescent is a criterion for hospital admission.
- ASTif neededBefore and at the start of refeeding in severe undernutrition: hepatic cytolysis, like hypophosphataemia, leads to energy intake being delayed by 24 to 48 h [2].
- ALTif neededBefore and at the start of refeeding in severe undernutrition: hepatic cytolysis, like hypophosphataemia, leads to energy intake being delayed by 24 to 48 h [2].
Bulimia (or binge-eating disorder): initial tests
Fasting laboratory tests
- FBC, platelets
- Haemostasis (PT, aPTT)
- Serum electrolytes
- Bicarbonate
- Serum creatinine with eGFR
- Fasting plasma glucose
- Serum magnesium (if laxatives or repeated vomiting)if needednon-French guidelineThe American Psychiatric Association (2023) describes hypomagnesaemia among the abnormalities linked to purging [4], the British MEED report links it to laxative abuse and an increased risk of arrhythmia [7], and the German association BFE measures magnesium from the outset [6]. The HAS (2019) does not list it in these initial tests [10].
- ECG in case of purging behaviours (vomiting, laxatives, diuretics).
Do not order
- Serum amylase: hyperamylasaemia (with normal lipase) accompanies vomiting, but its measurement is not indicated routinely [10].
Bulimia with vomiting, laxatives or diuretics: monitoring
Laboratory tests, to be repeated regularly
- Serum electrolytes (sodium, potassium)
- Bicarbonate
- Serum creatinine with eGFR
- Serum magnesium (if laxatives or repeated vomiting)if needednon-French guidelineThe British MEED report links hypomagnesaemia to laxative abuse and an increased risk of arrhythmia [7]; the American Psychiatric Association (2023) describes it among the abnormalities linked to purging [4]. The HAS (2019) does not cite it in this monitoring [10].
Also consider
- Vomiting, laxatives, diuretics? In case of vomiting, laxatives or diuretics, or low potassium, see the page Hypokaliémie.
Sources (12)
- Inserm. Anorexie mentale : un trouble essentiellement féminin, à la frontière de médecine somatique et de la psychiatrie. Dossier d'information.
- Anorexie mentale : prise en charge
- Centre de référence maladie rare Anorexie mentale à début précoce (Hôpital Robert-Debré, AP-HP). Protocole national de diagnostic et de soins (PNDS) : anorexie mentale à début précoce. Haute Autorité de santé, 15 juillet 2022.
- American Psychiatric Association. The American Psychiatric Association Practice Guideline for the Treatment of Patients With Eating Disorders, 2023 : diaporama de formation officiel de l'APA (recommandations 7 et 8, anomalies biologiques, syndrome de renutrition).
- Klein DA, Sylvester JE, Schvey NA. Eating Disorders in Primary Care: Diagnosis and Management. Am Fam Physician. 2021;103(1):22-32.
- Wünsch-Leiteritz W, Bundesfachverband Essstörungen (BFE). Welche Blutparameter sollten im ambulanten Rahmen (auch in betreuten Wohneinrichtungen für Essstörungen) bei Anorexia nervosa und Bulimia nervosa Patientinnen/Patienten bestimmt werden ? Empfehlung des BFE, 2019.
- Royal College of Psychiatrists. Medical Emergencies in Eating Disorders (MEED): Guidance on Recognition and Management. College Report CR233, mai 2022, mise à jour en décembre 2025.
- National Institute for Health and Care Excellence. Eating disorders: recognition and treatment. NICE guideline NG69, 23 mai 2017, dernière mise à jour le 16 décembre 2020.
- Hôpitaux universitaires de Genève. Protocole clinique de la prise en charge du syndrome de renutrition inappropriée (SRI). Référentiel HUG_000001197, version 1.0, applicable dès le 6 novembre 2024.
- Haute Autorité de santé, Fédération française anorexie boulimie (FFAB). Boulimie et hyperphagie boulimique : repérage et éléments généraux de prise en charge. Recommandation de bonne pratique, juin 2019.
- US Preventive Services Task Force. Screening for Eating Disorders in Adolescents and Adults: Recommendation Statement, 2022.
- Anorexie mentale : prise en charge