hematochezia.pptx

8/13/2019 HEMATOCHEZIA.pptx

1/26

HEMATOCHEZIA


2/26

DEFINITION

Hematochezia

bright red or maroon colored blood in the stool is

usually caused by lower GI bleeding

Melena

black, tarry stool which is foul smelling because of

the presence of partially digested blood products.

Melena implies that the blood has been in the GItract for at least 14 hours, & that usually indicates an

upper GI source.


3/26

Clinical Evaluation

Although the clinical history is frequentlyhelpful in identifying theprobable source of many upper GI bleedingepisodes, it is lesssowhen the bleeding source is the large or small bowel. In almost allcases the definitive diagnosis & frequently the management ismost often by endoscopy.

The single most important part of the clinical examination is tocarefully assess the vital signs, pulse, blood pressure, respiratoryrate & core body temperature. The examining physician is advisedto check these values personally as well as to evaluate the patientfor postural pulse/blood pressure changesindicative of significantloss of blood volume. Such loss may not be apparent from the

hematocrit or hemoglobin for 24 hours or more. The principle goal of the clinical evaluation is not to nail the

diagnosis of the bleeding source. It is rather to identify all probablecomplicating comorbidities in order to prevent acute complications.


4/26

Etiology

Differential Diagnosis of Lower Gastrointestinal Hemorrhage

COLONIC BLEEDING (95%) % SMALL BOWEL BLEEDING (5%)

Diverticular disease 30-40 Angiodysplasias

Ischemia 5-10 Erosions or ulcers (potassium, NSAIDs)

Anorectal disease 5-15 Crohn's disease

Neoplasia 5-10 Radiation

Infectious colitis 3-8 Meckel's diverticulum

Postpolypectomy 3-7 Neoplasia

Inflammatory bowel disease 3-4 Aortoenteric fistula

Angiodysplasia 3Radiation colitis/proctitis 1-3

Other 1-5

Unknown 10-25


5/26

Diverticulosis

Diverticulosis is the most common lower GI cause of hematocheziain adults & is progressively more likely with age.

The usual onset is the abrupt painless presentation of bright red ormaroon colored blood in the stool, which may be copious.

Eighty percent of bleeding episodes stop spontaneously & a

purgative bowel prep followed by colonoscopic diagnosis &intervention is the usually effective first management.

When bleeding is too brisk for proper visualization through thecolonoscope, angiographic embolization of the bleeding vessel isreportedly effective in 93% of cases in which embolization ispossible.

Elective segmental bowel resection may be required in patientswith repeated episodes of bleeding after endoscopic localization ofthe bleeding segment.


6/26


7/26

Ischemia Colitis

Ischemic Colitis is a very common cause of hematochezia in theelderly.

It is not caused by large artery occlusion but by impaired mucosalperfusion in watershed areas between the distributions of majorvascular territories.

The most frequent bleeding sites are the descending or sigmoidcolon.

Presentation is usually with cramping left sided abdominal painfollowed within 24 hours by hematochezia. Flat plate of theabdomen may show a classical thumbprints in the image of thecolonic mucosa at the site of the involved segment. Most episodesresolve with supportive care. Surgical intervention is reserved forpersistent hemorrhage & instances of septic clinical deterioration(fever, leukocytosis, etc).


8/26


9/26

Anorectal Disease

Rectal Hemorrhoids & Anal Fissures are the most common causesof hematochezia.

Usually symptoms are so mild that patients self medicate & do notseek medical attention. Bleeding from ulceration on a segment ofprolapsed rectal mucosa is more likely to provoke medical

consultation. Anorectal conditions account for about 8% in series of patients

presenting with hematochezia. It is axiomatic that finding one ofthese obvious lesions does not preclude the presence of acoexisting, more proximal & more serious lesion.

Full colonoscopicevaluation is indicatedfor all instances ofhematocheziaunless done previously within the past 2 years.These usually painful anorectal lesions rarely cause serious bleedingor require hospitalization.


10/26


11/26

Anal Fissure


12/26

Neoplasia

Benign & malignant colon tumor are increasinglyprevalent in elderly patients but also occur as early asthe 3rd or 4th decade in genetically predisposedpatients.

Although they are usually discovered by screeningcolonoscopy or present with mild intermittent or occultbleeding, they occasionally present with grosshemorrhage.

Diagnosis & treatment are almost always preformedendoscopically with small early lesions & surgicalintervention for more extensive disease.


13/26

Colon Cancer


14/26

Infectious Colitis

Infectious Colitis caused by Campylobacter

jejuni, Shigella or Salmonella species,

pathogenic E coli, Clostridium difficile or E. coli

0157:H7 may cause bloody diarrhea.

Blood loss is rarely significant & the need for

specific treatment is determined by stool

culture & stool antigen assays.


15/26

Pseudomembran Colitis


16/26

Post Polipectomy

occurs within 2 weeks following about 3% of

endoscopic polypectomies. About 50% require

transfusion.

Most such patients have a concomitant

bleeding risk like aspirin or warfarin therapy &

> 95% are amenable to endoscopic treatment.


17/26

Inflamatory Bowel Disease Inflammatory Bowel Disease (IBD): The peak incidence of IBD is bimodal,

the 1st peak occurring in the early 20s & the 2nd around age 70. Ulcerative colitis (UC) is much more likely to present with hematochezia

than is Crohnsdisease (CD). Fifteen percent present with UC catastrophic

onset; 1% with massive hematochezia.

Most UCpatients report a long history of tenesmus, cramping abdominal

pain & sometimes intermittent mucoid stools prior to the first episode ofbleeding. 95% of UC patients have rectal mucosal involvement. Crohns

patients by contrast usually have a chronic history of recurrent colicky

right lower quadrant abdominal pain, sometimes accompanied by fever,

mimicking acute appendicitis. Although diarrhea is characteristic of acute

flares of Crohnsdisease, gross bleeding is uncommon & only 1 to 2%bleed massively.

Symptoms of bowel obstruction are more characteristic of Crohnsdisease

& perirectal disease is much more frequent, affecting about . The gross

appearance of the diffusely bright red inflamed colonic mucosa usually

distinguishes UCfrom the skip areas, cobble-stone appearance, linearulcerations & aphthus ulcers of Crohnsdisease.


18/26

Ulcerative Colitis


19/26

CrohnsDisease


20/26

Angiodysplasia

Angiodysplasia is probably the next most frequentlyseen lower GI cause of hematochezia. Two thirds ofthese patients are over 70 years of age, are more malethan female & associated with the presence of aortic

valvular stenosis. The bleeding site is identified by colonoscopy in 80 to

90% of cases & is generally amenable to localtreatment. Bleeding recurs in about 20%. When

colonoscopic electrocautery fails to control bleedingangiography & arterial embolization may be effective.In severe cases colonic resection may be required.


21/26

Angiodysplasia colon


22/26

Post Radiation Colitis

Post-Radiation Colitis may occur immediately or may occurseveral years after radiation therapy for pelvic or colorectalcancer. A 3 year incidence of 14.3% was recently reported.

Significant risk factors included age >60 & external beamradiation doses > 54Gy. Symptoms of proctitis & rectalbleeding may be troublesome & recurrent owing torecurring flairs of radiation induced vasculitis.

Blood loss is rarely massive but chronic iron deficiencyanemia is not.

The condition tends to improve with time. Local enemas &cutaneous application of steroid or 5-ASA creams isconventionally given but treatment is often unsatisfactory.


23/26


24/26


25/26

Solitary Ulcers of the Small Bowel, Colon or

Rectum usually associatedwith long termNSAIDuse may also cause hematochezia.

Blood loss is rarely significant & specific

treatment usually is generally unnecessary.


26/26

Undetermined

In about 15% of cases in most series the source ofbleeding remains unknown.

Even those series in which extraordinary followupexaminations were performed ended with 5%

diagnostic failures.

In elderly adults such cases are most likely related tosmall vascular ectasias (dilatation) that lack sufficientsize for ready identification via the colonoscope.

In young patients MTcpertechnetate scininigraphy(radio medicine) may identify about 65% of Meckelsdiverticulae

hematochezia.pptx

Documents