GERD
Heartburn
Gastroesophageal Reflux Disease (GERD) is when stomach acid burns the esophagus. It’s very common.
If you did a handstand right now, would stomach acid pour out of your mouth? Of course not. Stomach acid simply cannot flow into the esophagus. That’s thanks to a muscle called the lower esophageal sphincter (LES). Stomach acid shouldn’t be in the esophagus, but it can sneak in if the LES is weak and floppy. We don’t know why, but sometimes the LES does this. While the exact MOA is unknown, some risk factors have been identified: pregnancy, alcohol, smoking, obesity, fatty foods, caffeine and hiatal hernias. We know that babies have wimpy LES’s. That explains why they frequently get GERD. Since they can’t complain of heartburn, try PPIs on any baby with unexplained spit ups and fussiness. Pregnancy causes LES floppiness because of the high levels of progesterone, a known smooth muscle cell relaxer.
The main symptom of GERD is heartburn -- retrosternal burning chest pain following meals or while laying down. It often leaves a bad “lava” taste in the back of your mouth. If the stomach acid is accidentally inhaled down the trachea, then respiratory problems can occur: nocturnal cough & SOB.
The consequences of untreated GERD include ulcers and strictures. Ulcers (epithelial damage) occur whenever acid completely erodes a patch of epithelium. Ulcers are quite painful. These ulcers are repaired with fibrosis. Uneven or heavy fibrosis can lead to strictures, which cause serious dysphagia (difficulty swallowing). Another important consequence is Barrett’s Esophagus (BE), which is a precancerous condition caused by chronic GERD. GERD damages the esophagus. The esophagus can’t handle the acid. So its epithelium adapts, evolving into columnar epithelium. When cells dramatically change, we call it metaplasia. The cells physically elongate. Crypts and goblet cells appear. The squamocolumnar junction creeps upward into the esophagus. Barrett’s Esophagus is a precancerous condition. It can progress into esophageal adenocarcinoma. On an EGD, look for dark pink tissue on the distal third of the esophagus (normal esophagus is a pale pink color). Note - it’s called the Z-line because it’s a bit jagged.
The treatment of GERD should begin with weight loss and trigger avoidance. Foods that are acidic, fatty or spicy can trigger GERD. But lifestyle changes sometimes don’t stick. Medical therapy of GERD is dominated by Proton Pump Inhibitors (PPIs), which all end in -prazole. They work by inhibiting the proton-potassium pump in parietal cells. PPIs are safe and effective! Note that discontinuing PPIs will result in Gastrin-mediated rebound acid hypersecretion. In the past, before PPIs, therapy consisted of H2 Histamine Blockers (-tidine). They obviously blocked H2 receptors, which are found on parietal cells. They have more side effects than PPIs. Severe refractory GERD can be treated surgically with a Nissen Fundoplication, where a piece of the upper stomach is wrapped around the LES and stapled into place.
E = Eosinophil N = Neutrophil
ESOPHAGEAL CANCER
Esophageal cancer has a poor prognosis. By the time it becomes symptomatic, it’s often already stage 3 or 4. The classic symptom is solid food dysphagia. It can also cause a variety of other symptoms, like a cough, hoarseness, weight loss or hematemesis. If you suspect it, get an EGD. There are two major kinds of esophageal cancer.
Lymphatic Drainage of the Esophagus
Upper Esophagus → Neck
Middle Esophagus → Chest (Mediastinal)
Lower Esophagus → Abdomen (Celiac, Gastric)
ESOPHAGITIS
Infectious Esophagitis is only seen with immunocompromised states. These are all AIDS-defining lesions. These are high yield!
Eosinophilic Esophagitis is an allergic reaction in the esophagus. It’s most common in young adult males with a history of atopy (asthma, eczema). It causes dysphagia. EGD shows rows of ringed strictures. Biopsy shows a lot of Eosinophils (duh). Consider EE whenever a patient with dysphagia doesn’t respond to PPIs. Interestingly, the ringed pattern is seen in the normal cat esophagus, which is why this is sometimes termed “feline esophagitis.”
Irritant Esophagitis is when a caustic substance inflames the esophagus. Some pills are irritating to the esophagus, and they should be taken with plenty of water while the torso is upright (and don’t lay down for a while). Some of the most caustic pills include bisphosphonates, iron tablets, doxycycline, NSAIDs and potassium-chloride. Lye is an interesting case, because it tends to cause stricture formation years down the road.
DYSPHAGIA
Difficulty swallowing
Dysphagia is a common symptom in the world of gastroenterology. It would be helpful to classify the different patterns and causes of dysphagia.
If you can swallow liquids but not foods (solid dysphagia), then the cause is mechanical. Something has grown into the lumen of your esophagus. It could be a tumor, stricture or web. While cancers can obviously grow large enough to block the entire esophagus, that takes a long time -- the initial symptom will be solid dysphagia.
If you suddenly can’t swallow foods or liquids (solid and liquid dysphagia), then the cause is a problem with muscular motility. Since massive tumors don’t grow overnight. Something is interfering with the esophageal muscles. You could have a disease that affects the skeletal muscle at the top third of your esophagus (myasthenia gravis, stroke) or the smooth muscle at the bottom third (achalasia, systemic sclerosis, CREST syndrome).
In any case, you need a barium study and/or an EGD (Esophagogastroduodenoscopy). If the cause is a motility problem, then performing an esophageal manometry study is especially helpful. It’s sort of like an EKG study of the throat muscles, as it graphs the pressure forces during a swallow. This can hopefully identify a lesion!
ACHALASIA
Tight LES
Achalasia is an inability to relax the LES. It’s due to loss of inhibitory ganglion cells in Auerbach’s plexus. Without inhibitory ganglia, there is a decrease in endogenous smooth muscle relaxing peptides like NO and VIP. The cause is often idiopathic, although it can be caused by Chagas Disease in South America (T. cruzi protozoa spread by Reduviid “kissing bug,” which also causes cardiomyopathy).
Symptoms include dysphagia to liquids and solids, bad breath (food stuck in esophagus) and perhaps heartburn. Diagnose with a barium swallow, looking for the characteristic bird’s beak. You can also diagnose it with Esophageal Manometry to measure pressure changes in the esophagus. LES tone is high in achalasia, and low in scleroderma. You can treat Achalasia with dilation, surgery (esophagomyotomy) or medications (nitrates, CCBs, botox).
Diffuse Esophageal Spasm is a self-explanatory condition. The esophagus occasionally clamps down, producing sudden chest pain. EGDs can miss the diagnosis if the study takes place in between spasms. The diagnosis is made with manometry.
ESOPHAGEAL VARICES
Huge throat veins
Varices are dilated submucosal veins in the lower esophagus. The cause of dilation is high pressure. Esophageal vein pressure accumulates in the setting of portal hypertension. That occurs when there is a problem in the liver such as cirrhosis. Varices will eventually burst and cause life-threatening hematemesis. With a broken liver, they will lack clotting factors, and they won’t be able to staunch the bleeding. Propranolol and Octreotide (a Somatostatin analog) are helpful prophylaxis medications that work by constricting the splanchnic circulation. In the event of rupture, the case fatality rate is over 50% even with surgery or the temporary Blakemore tube (curiously, they also benefit from antibiotics). For that reason, cirrhotic patients should get routine EGDs, so that a gastroenterologist can band or ligate varices before they can pop. This is the most common cause of death in cirrhosis.
Classic Patient - an alcoholic with ascites who suddenly begins vomiting blood.
ESOPHAGEAL TEARS
Rip
Mallory-Weiss Tears are superficial tears in the esophagus -- confined to the mucosa and submucosa. The tear usually occurs near the LES. Conditions that cause a lot of vomiting (eg, bulimia, alcoholism, really bad food poisoning, vertigo, etc) cause MW Tears. They cause mild hematemesis or hemoptysis, but thankfully it’s rarely fatal. This will heal spontaneously in a few days.
Boerhaave Tears (transmural tears) are deep esophageal tears past the submucosa. Boerhave Tears can also be caused by prolonged violent retching, but the most common cause is iatrogenic esophageal instrumentation. Other causes include cancer, trauma, foreign body ingestion (ie, a fish bone) or just spontaneously. The patient will present with severe hematemesis, pain, dyspnea and shock. Interestingly, they often have a fever. As air exits the esophagus it enters the mediastinum. That is called a pneumomediastinum. It can be seen on a chest x-ray as a sliver of air around the heart. If crepitus is palpable over the heart, it’s called Hamman’s sign. The air can also leak into soft tissue and skin around the neck and shoulders (subcutaneous emphysema), causing crepitus (rice crispy palpation).
➭ Pneumomediastinum
STRUCTURAL ESOPHAGEAL DEFECTS
Zenker’s Diverticulum is an upper esophageal outpouching. It occurs due to hypertonicity of the cricopharyngeus muscle. Dysphagia occurs because there’s a literal lump in your throat. The bubble fills up with food, causing halitosis and regurgitation. Diagnose with a Barium Swallow.
Esophageal Webs and Rings are little blobs of tissue growth that occur in the lumen. Rings are circumferential, webs are not. They can cause mechanical dysphagia. They carry a slight risk for Squamous Cell Carcinoma.
Plummer-Vinson Syndrome is the triad of a web, glossitis and iron deficiency anemia. It’s rare and poorly understood. It tends to affect middle aged white women.
CONGENITAL UPPER GI
Esophageal Atresia with Tracheoesophageal Fistula is a popular topic in pediatric textbooks. It’s a component of VACTERL syndrome (Vertebrae, Anal atresia, Cardiac, TracheoEsophageal fistula, Renal, Limbs).
A Congenital Diaphragmatic Hernia occurs when the pleuroperitoneal membrane never closes in utero, allowing the bowel to enter the chest cavity. The guts compete for space with one of the lungs. This causes life-threatening respiratory distress, and requires a rapid surgical correction. These usually occur on the left side of the chest, because the liver “protects” the right sided diaphragm.
Bowel loops in the chest cavity. There’s a fart in that chest!