Case 1: Recurrent iron-deficiency anemia in a teenager
Notice bibliographique
Résumé
A 16-year-old girl was referred by her paediatrician for evaluation of persistent microcytic anemia. Two years previously, she presented to her local hospital complaining of fatigue and weakness. At that point, her hemoglobin level was 46 g/L, with a low mean corpuscular volume and decreased iron and ferritin levels. She had no evidence of gastrointestinal bleeding and was otherwise healthy. Furthermore, she reported a regular menstruation cycle without increase in blood loss. She received a blood transfusion and was started on iron supplements, to which she had a good response as her hemoglobin level rose up to 129 g/L. Her clinical symptoms also resolved and iron supplementation was discontinued one year later. However, on follow-up, her hemoglobin level dropped to 85 g/L. Again, her iron stores were considerably low. A hemoglobin electrophoresis was normal. She still had no history of overt bleeding, but one of three fecal occult blood tests was positive. She was then evaluated in our centre. The physical examination was unremarkable apart from a small hemangioma of the tongue. Both upper endoscopy and colonoscopy showed no source of bleeding. A small bowel follow-through was normal. Further investigations revealed the diagnosis. Given the positive fecal occult blood test, we elected to proceed with a videocapsule endoscopy to better assess the small intestine. Capsule endoscopy showed a bluish subepithelial mass in the mid-jejunum. To better evaluate the lesion, the patient then underwent single-balloon enteroscopy. This procedure showed a 2.5 cm-wide purple-red polypoid lesion of the mid-jejunum (Figure 1). Because the patient had a small hemangioma of the tongue, a small bowel hemangioma was suspected. No biopsy was attempted during single-ballon enteroscopy. A paediatric surgeon resected the affected segment of small bowel. Pathological examination confirmed a 3.0 cm x 1.8 cm capillary hemangioma. The recovery was uneventful. Single-balloon enteroscopy showing the polypoid lesion of the mid-jejunum Hemangiomas are classified as benign vascular tumours. There are three types of intestinal hemangiomas: cavernous, capillary and mixed. The small intestine is the most common site of gastrointestinal hemangiomas, with the jejunum the most likely affected segment. Hemangiomas account for 7% to 10% of the benign tumours of the small bowel (1). These tumours may manifest as solitary or multiple lesions. Multiple lesions are typically associated with cutaneous vascular lesions or syndromes. Most patients present with either acute or chronic symptoms of gastrointestinal bleeding, including chronic microcytic anemia. Small bowel obstructions or intussusceptions have been reported as primary manifestations of large hemangiomas. Microcytic anemia is a relatively common hematological condition in children. The differential diagnosis is quite broad and includes iron and copper deficiencies, anemia of chronic disease, sideroblastic anemia, lead poisoning and thalassemia. In iron-deficiency anemia, iron studies usually show decreased ferritin and serum iron levels, an elevated serum transferrin level and a high total iron binding capacity. Unless there is clear history of low dietary intake of iron, the clinician should initiate evaluation for a source of bleeding or a malabsorptive process. Beyond infancy, dietary iron deficiency is rare. Therefore, it should be regarded as a manifestation of an underlying disorder and not as a diagnosis. Malabsorptive conditions such as celiac disease and inflammatory bowel disease should be considered. As well, chronic occult blood loss should be investigated (esophagitis, peptic ulcer, vascular malformation). In girls, a careful history on menstrual blood loss should be taken. If investigations demonstrate occult gastrointestinal bleeding, this should prompt the clinician to find the source. When standard investigations, such as an upper endoscopy and a colonoscopy, fail to demonstrate a source, further evaluation for occult gastrointestinal bleeding is indicated. A small bowel follow-through is a useful tool; however, it may miss small lesions. Wireless capsule endoscopy is a noninvasive procedure that enables the visualization of the entire small bowel. As it progresses in the small bowel, several images of the mucosa are captured. The capsule may be either swallowed or inserted in the duodenum using an endoscope. It is limited by the fact that it does not permit tissue sampling or therapeutic intervention. There has been considerable literature regarding its safe use in paediatric patients (2). Another way to explore the small bowel is by using enteroscopy. This endoscopic procedure is also known as push-and-pull enteroscopy, and enables visualization and therapy of the entire small bowel. The endoscope is covered by an overtube that is also fitted with a balloon (commonly a double-balloon system). Serial inflation and deflation of balloons allow pleating of bowel on the back of the overtube and forward advancement of the enteroscope into a new segment of bowel. Recent studies have reported its safety and efficacy in paediatric patients. In summary, recurrent or persistent iron-deficiency anemia must be investigated thoroughly. Occult gastrointestinal bleeding needs to be excluded. Iron-deficiency anemia in children needs to be investigated to identify a cause because dietary iron deficiency is rare beyond infancy. Occult gastrointestinal bleeding in children needs to be investigated with appropriate tests, including imaging of the entire gastrointestinal tract if no source is initially found. Vascular lesions of the small bowel, such as hemangioma, represent a rare but possible cause of recurrent or persistent iron-deficiency anemia in children.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,004 |
| Méta-épidémiologie (sens strict) | 0,001 | 0,001 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,002 | 0,001 |
| Études des sciences et des technologies | 0,002 | 0,001 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,003 | 0,002 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,004 | 0,001 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».