Diverticulitis

Diverticula: Outpouchings along the mucosal wall of the colon.

Diverticulosis: Refers to the presence of uninflamed diverticula and is the most common cause of lower GI bleeding.

Diverticulitis: Inflamed diverticula which result from obstruction/infection of diverticula.

Pathophysiology

The Sigmoid colon is the most common area for diverticula to occur due to high intraluminal pressure. Additional risk factors include low fiber diet, constipation, and obesity.

Clinical Manifestation

Patients are usually asymptomatic. Once obstructed the diverticula become distended causing left lower quadrant (LLQ) discomfort which is the most common clinical symptom of diverticulitis.

Additional Symptoms: fever, nausea, vomiting, diarrhea, constipation and bloating.

Diagnosis

CT abdomen/pelvis is the test of choice to diagnose diverticulitis.

Barium enema could also provide a diagnosis and should not be performed in the acute phase.

Patients may also have leukocytosis or positive guaiac test.

Treatment

Patients with diverticulitis should be remain NPO and started on antibiotics to treat the infection.

Ciprofloxacin or Bactrim combined with Metronidazole

Patients with known diverticulosis should be advised to follow a high fiber diet or obtain fiber supplements. Roughly 90% of patients with a positive guaiac test 90% experience bleeding resolution. In cases of continued bleeding patients may be given vasopressin to help facilitate hemorrhage resolution.  

Esophageal Varices

Overview

Esophageal varices are dilated submucosal veins in the distal esophagus that develop as a consequence of portal hypertension, with the most common risk factor being cirrhosis. They are clinically significant because of their high risk of life-threatening upper gastrointestinal bleeding and account for 5-11% of upper GI bleeds. Early recognition and appropriate management are essential in both inpatient and outpatient settings.

Pathophysiology

Esophageal varices result from increased pressure within the portal venous system. Blood drains from portions of the GI tract into the portal vein which flows through the liver before returning to systemic circulation. The liver normally offers low resistance to portal blood flow, however, conditions impacting liver function such as cirrhosis increase the intrahepatic vascular resistance causing portal hypertension. Blood is then redirected thought portosystemic collateral pathways to bypass the liver due to the high pressure gradient. One of these collateral pathways involves veins in the distal esophagus which become thin and tortuous from the increased blood volume traveling through these vessels which lack structural support making them prone to rupture.

Clinical Manifestation

Many patients with esophageal varices are asymptomatic until bleeding occurs which can cause hematemesis, melena, or hematochezia. Additional symptoms of acute bleeding include lightheadedness, syncope, fatigue, weakness, hypotension, and tachycardia. Signs of chronic liver disease such as jaundice, ascites, spider angiomas, and splenomegaly may also be present. If left untreated bleeding varices can lead to hypovolemic shock.

Diagnosis

Upper endoscopy (EGD) remains the gold standard for screening. Patients with newly diagnosed cirrhosis should undergo screening endoscopy.

Treatment

In cases of acute bleeding endoscopic ligation is the treatment of choice as well as securing an airway, fluid replenishment, and correcting any coagulopathies present. Octreotide, a somatostatin analog, or vasopressin may also be used in cases of acute bleeds to reduce portal venous pressure.

Approximately 70% of varices rebleed within 1 year of the initial bleed (1/3 of these rebleeds are fatal) making prevention of rebleeding very important in treatment of patients with known esophageal varices. Non-selective beta blockers such as propranolol or nadolol are both used to reduce portal venous pressure outside of acute bleeds by 1) decreasing cardiac output due to β1 blockade and 2) causing splanchnic vasoconstriction due to β2 blockade. Beta blockers are contraindicated in acute bleeds to avoid lowering the tachycardic response to hypovolemia and reducing cardiac output. The long-acting nitrate Isosorbide may also be used to reduce esophageal variceal pressure. Additionally, a transjugular intrahepatic portosystem shunt (TIPPS) may be an option for patients with varices refractory to the above mentioned treatments.