Approach to hematochezia (pediatrics): Clinical sciences

Hematochezia refers to the passage of bright red blood per rectum. The presence of hematochezia suggests a source of bleeding distal to the ligament of Treitz, in the small bowel or colon.

Hematochezia can be an incidental finding and asymptomatic if blood loss is minor or occult; however, patients with brisk or heavy bleeding can develop anemia or even hemorrhagic shock.

If a pediatric patient presents with hematochezia, you should first perform an ABCDE assessment to determine if they are stable or unstable.

If unstable, stabilize the airway, breathing, and circulation. Next, obtain intravenous or intraosseous access, and consider administering IV fluids and a transfusion of packed red blood cells. Finally, remember to place your patient on continuous vital sign monitoring and provide supplemental oxygen if needed.

Here’s a clinical pearl! Patients with brisk gastrointestinal bleeding can decompensate quickly, so monitor your patient closely for signs of hemorrhagic shock, like tachypnea, tachycardia, and hypotension.

Remember to also consider the possibility of an upper gastrointestinal source of bleeding for any patient with hematochezia and rapid blood loss.

Alright, let’s go back to the ABCDE assessment and look at stable patients. First, perform a focused history and physical examination and obtain a fecal occult blood test.

Here’s a high-yield fact! It’s important to perform fecal occult blood testing since many ingested substances can mimic hematochezia by making the stool appear red. Some common culprits include beets, blueberries, tomatoes, candy, or crayons.

As far as the history goes, patients or their caregivers typically report seeing bright red blood in the stool. If the bleeding is chronic, the patient may report fatigue or shortness of breath. Additionally, some patients may have coexisting constipation or diarrhea.

Physical exam might reveal abdominal distension and tenderness, as well as visible rectal bleeding. Finally, the fecal occult blood test will be positive. With these findings, consider a lower gastrointestinal bleed, and assess your patient’s general appearance.

Here’s another clinical pearl! During your initial evaluation of hematochezia, consider ordering labs like a CBC, CMP, PT, and PTT, since abnormal results can identify other underlying conditions.

For instance, the CBC may reveal anemia or thrombocytopenia, while elevated creatinine suggests acute kidney injury. Keep in mind that elevated BUN may be seen in these patients, which is not due to kidney injury but from the absorption of blood products from the GI tract. Finally, if PT or PTT are prolonged, consider the possibility of an inherited or acquired bleeding disorder.

First, let’s take a look at ill-appearing patients. Before you proceed any further, assess for the presence of fever. If your patient is afebrile, you’ll need to assess for abdominal pain.

Severe, acute abdominal pain should immediately make you consider an intestinal obstruction due to intestinal malrotation with volvulus or intussusception. Keep in mind that both are surgical emergencies requiring urgent intervention.

Let’s start with intestinal malrotation with volvulus. These patients usually present during infancy with bilious vomiting, while the physical exam reveals abdominal distension and tenderness. Bilious vomiting in an infant is a red flag that should immediately make you consider intestinal malrotation with volvulus.

This can’t-miss condition results from defective embryonic rotation of the gut, which causes the intestines to twist around their mesenteric root.

Consequently, these infants can quickly develop vascular compromise and bowel ischemia. Therefore, order an emergent upper GI contrast study.

Imaging will show a spiral appearance of the duodenum and jejunum called the “corkscrew sign”, confirming the diagnosis of intestinal malrotation with volvulus.

Let’s move on to intussusception. These patients typically present between the ages of 6 and 36 months with lethargy, irritability, and colicky abdominal pain. Some pass stool containing blood and mucus, giving it an appearance resembling “red currant jelly”.

The exam might reveal a sausage-shaped mass in the right upper quadrant, possibly with abdominal tenderness. With these findings, consider intussusception and promptly obtain an abdominal ultrasound.

If it reveals a proximal segment of bowel telescoping into a distal segment, as well as concentric bands alternating in echogenicity, creating the “target sign”, that's intussusception.

Here’s a high-yield fact! In children over 3 years of age, intussusception is often associated with anatomic anomalies. These anomalies function as “lead points” that cause one segment of the intestine to “telescope” into an adjacent segment.

Some conditions that create “lead points” include Meckel diverticulum, lymphonodular hyperplasia, tumors, polyps, or intestinal duplication cysts. Additionally, children have a slightly increased risk of intussusception 1 to 2 weeks after receiving the rotavirus vaccine.

Now let’s back up and consider ill-appearing patients who don’t have abdominal pain. In which case you should consider Meckel diverticulum.

In this condition, an outpouching in the lower gastrointestinal tract contains a remnant of embryonic tissue that consists of ectopic gastric mucosa. The ectopic tissue secretes non-neutralized acid, which eventually creates bleeding ulcers in the adjacent intestinal mucosa.

Affected patients are typically under 2 years of age and present with brisk, profuse rectal bleeding, while the exam reveals a nontender abdomen. As a next step, order a Technetium 99 scan, also known as a Meckel scan.

The ectopic gastric mucosa within the diverticulum will collect the Technetium 99, resulting in a positive test and a diagnosis of Meckel diverticulum.

Here’s a clinical pearl! In practice, an endoscopy is usually performed before ordering a Technetium 99 scan to rule out other causes of bleeding first.

Time for another high-yield fact! The “rule of 2” is used to describe Meckel diverticulum, since it usually occurs within 2 feet of the ileocecal valve; is 2 inches long; and occurs in around 2 percent of the population. Additionally, there is a 2-to-1 male-to-female ratio, and 2 percent of affected individuals develop complications before 2 years of age.

Alright, let’s switch gears and discuss ill-appearing patients who are febrile. Here, you should consider inflammatory processes, such as ulcerative colitis and infectious enterocolitis.