9.7
Stenosi esofagee I: Introduzione
Le stenosi esofagee comportano un restringimento o un serraggio anomalo dell'esofago. Variano in lunghezza e gravità, spaziando da una lieve costrizio…
Le stenosi esofagee si riferiscono al restringimento anomalo o al restringimento del lume esofageo, che va da una lieve costrizione a un'ostruzione completa.
La causa più comune di stenosi esofagee è il reflusso acido cronico, che innesca infiammazioni, danni e cicatrici il rivestimento esofageo, portando a stenosi.
L'ingestione accidentale o intenzionale di acidi o alcali danneggia l'esofago, con acidi che causano necrosi coagulativa e alcali che causano necrosi liquefattiva; entrambi possono provocare la formazione di stenosi.
Inoltre, la radioterapia alle regioni cervicali o toraciche per il trattamento del cancro può danneggiare l'esofago, causando stenosi esofagea indotta da radiazioni.
La prossima è l'esofagite eosinofila, una condizione allergica in cui l'esofago si riempie di eosinofili, causando gonfiore, restringimento e stenosi esofagea.
Infine, i danni causati dalle procedure endoscopiche possono causare traumi fisici al rivestimento esofageo, portando a stenosi esofagee.
Altre cause di stenosi esofagee includono tumori, stenosi esofagee congenite, uso prolungato di FANS, uso prolungato del sondino nasogastrico, chirurgia di fundoplicatio GERD Nissen e presenza di corpi estranei nell'esofago.
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Q1: What causes esophageal strictures?
The primary cause of esophageal strictures is chronic gastroesophageal reflux disease, accounting for 70-80% of adult cases. Acid reflux damages and scars the esophageal lining, leading to narrowing. Other causes include ingestion of corrosive substances, radiation therapy to the chest or neck, eosinophilic esophagitis, endoscopic trauma, tumors, prolonged nasogastric tube use, and post-surgical complications.
Q2: How do acids and alkalis damage the esophagus differently?
Acids cause coagulative necrosis, which creates a defined boundary of tissue death. Alkalis cause liquefactive necrosis, resulting in deeper, more diffuse tissue damage. Both types of chemical injury can lead to stricture formation as the esophagus heals and scars. The extent of damage depends on the concentration, duration of contact, and type of substance ingested.
Q3: What is eosinophilic esophagitis and how does it cause strictures?
Eosinophilic esophagitis is an allergic condition where eosinophils accumulate in the esophageal tissue, causing inflammation and swelling. This inflammatory response narrows the esophageal lumen, potentially leading to stricture formation. The condition represents an immune-mediated response rather than infectious or mechanical obstruction.
Q4: How can radiation therapy lead to esophageal strictures?
Radiation therapy targeting the cervical or thoracic regions for cancer treatment can damage the esophageal tissue as a long-term complication. The targeted radiation harms surrounding soft tissues, including the esophagus, causing scarring and fibrosis. Strictures typically develop within a median of 6 months post-treatment as the tissue heals abnormally.
Q5: How do malignant tumors cause esophageal narrowing?
Malignant tumors infiltrate the esophageal layers—mucosa, submucosa, muscularis propria, and adventitia—causing scarring and fibrosis that narrows the lumen. Additionally, tumors in adjacent organs or lymph nodes exert external pressure on the esophagus, further constricting it. This dual mechanism of internal infiltration and external compression leads to stricture formation.
Q6: What is the difference between benign and malignant esophageal strictures?
Benign strictures are noncancerous narrowings caused by inflammation, scarring, or trauma from conditions like GERD, chemical ingestion, or radiation. Malignant strictures result from cancerous tumor infiltration and growth within the esophageal layers. Both types vary in length and severity, ranging from mild constriction to complete obstruction, but require different management approaches.
Q7: What other risk factors can contribute to esophageal stricture development?
Additional risk factors include congenital abnormalities, prolonged nasogastric tube use that causes mechanical irritation, long-term NSAID medication use that damages the lining, and post-surgical complications following fundoplication for GERD. Endoscopic procedures can also cause physical trauma leading to strictures. Foreign objects lodged in the esophagus represent another potential cause.