Acute Appendicitis

EpidemiologyThe incidence of appendectomy appears to be declining due to more accurate preoperative diagnosis.Despite newer imaging techniques, acute appendicitis can be very difficult to diagnose.

PathophysiologyAcute appendicitis is thought to begin with obstruction of the lumenObstruction can result from food matter, adhesions, or lymphoid hyperplasiaMucosal secretions continue to increase intraluminal pressure

PathophysiologyEventually the pressure exceeds capillary perfusion pressure and venous and lymphatic drainage are obstructed.With vascular compromise, epithelial mucosa breaks down and bacterial invasion by bowel flora occurs.

PathophysiologyIncreased pressure also leads to arterial stasis and tissue infarctionEnd result is perforation and spillage of infected appendiceal contents into the peritoneum

PathophysiologyInitial luminal distention triggers visceral afferent pain fibers, which enter at the 10th thoracic vertebral level.This pain is generally vague and poorly localized.Pain is typically felt in the periumbilical or epigastric area.

PathophysiologyAs inflammation continues, the serosa and adjacent structures become inflamed This triggers somatic pain fibers, innervating the peritoneal structures.Typically causing pain in the RLQ

PathophysiologyThe change in stimulation form visceral to somatic pain fibers explains the classic migration of pain in the periumbilical area to the RLQ seen with acute appendicitis.

PathophysiologyExceptions exist in the classic presentation due to anatomic variability of the appendixAppendix can be retrocecal causing the pain to localize to the right flankIn pregnancy, the appendix ca be shifted and patients can present with RUQ pain

PathophysiologyIn some males, retroileal appendicitis can irritate the ureter and cause testicular pain.Pelvic appendix may irritate the bladder or rectum causing suprapubic pain, pain with urination, or feeling the need to defecateMultiple anatomic variations explain the difficulty in diagnosing appendicitis

HistoryPrimary symptom: abdominal pain to 2/3 of patients have the classical presentationPain beginning in epigastrium or periumbilical area that is vague and hard to localize

HistoryAssociated symptoms: indigestion, discomfort, flatus, need to defecate, anorexia, nausea, vomitingAs the illness progresses RLQ localization typically occursRLQ pain was 81 % sensitive and 53% specific for diagnosis

HistoryMigration of pain from initial periumbilical to RLQ was 64% sensitive and 82% specificAnorexia is the most common of associated symptomsVomiting is more variable, occuring in about of patients

Physical ExamFindings depend on duration of illness prior to exam.Early on patients may not have localized tendernessWith progression there is tenderness to deep palpation over McBurneys point

Physical ExamMcBurneys Point: just below the middle of a line connecting the umbilicus and the ASISRovsings: pain in RLQ with palpation to LLQRectal exam: pain can be most pronounced if the patient has pelvic appendix

Physical ExamAdditional components that may be helpful in diagnosis: rebound tenderness, voluntary guarding, muscular rigidity, tenderness on rectal

Physical ExamPsoas sign: place patient in L lateral decubitus and extend R leg at the hip. If there is pain with this movement, then the sign is positive.Obturator sign: passively flex the R hip and knee and internally rotate the hip. If there is increased pain then the sign is positive

Physical ExamFever: another late finding.At the onset of pain fever is usually not found. Temperatures >39 C are uncommon in first 24 h, but not uncommon after rupture

DiagnosisAcute appendicitis should be suspected in anyone with epigastric, periumbilical, right flank, or right sided abd pain who has not had an appendectomy

DiagnosisWomen of child bearing age need a pelvic exam and a pregnancy test.Additional studies: CBC, UA, imaging studies

DiagnosisCBC: the WBC is of limited value. Sensitivity of an elevated WBC is 70-90%, but specificity is very low.But, +predictive value of high WBC is 92% and predictive value is 50%CRP and ESR have been studied with mixed results

DiagnosisUA: abnormal UA results are found in 19-40%Abnormalities include: pyuria, hematuria, bacteruriaPresence of >20 wbc per field should increase consideration of Urinary tract pathology

DiagnosisImaging studies: include X-rays, US, CTXrays of abd are abnormal in 24-95%Abnormal findings include: fecalith, appendiceal gas, localized paralytic ileus, blurred right psoas, and free airAbdominal xrays have limited use b/c the findings are seen in multiple other processes

DiagnosisGraded Compression US: reported sensitivity 94.7% and specificity 88.9%Basis of this technique is that normal bowel and appendix can be compressed whereas an inflamed appendix can not be compressedDX: noncompressible >6mm appendix, appendicolith, periappendiceal abscess

DiagnosisLimitations of US: retrocecal appendix may not be visualized, perforations may be missed due to return to normal diameter

DiagnosisCT: best choice based on availability and alternative diagnoses.In one study, CT had greater sensitivity, accuracy, -predictive value Even if appendix is not visualized, diagnose can be made with localized fat stranding in RLQ.

DiagnosisCT appears to change management decisions and decreases unnecessary appendectomies in women, but it is not as useful for changing management in men.

Special PopulationsVery young, very old, pregnant, and HIV patients present atypically and often have delayed diagnosisHigh index of suspicion is needed in the these groups to get an accurate diagnosis

TreatmentAppendectomy is the standard of carePatients should be NPO, given IVF, and preoperative antibiotics Antibiotics are most effective when given preoperatively and they decrease post-op infections and abscess formation

TreatmentThere are multiple acceptable antibiotics to use as long there is anaerobic flora, enterococci and gram(-) intestinal flora coverageOne sample monotherapy regimen is Zosyn 3.375g or Unasyn 3gAlso, short acting narcotics should be used for pain management

DispositionAbdominal pain patients can be put in 4 groupsGroup 1: classic presentation for Acute appendicitis- prompt surgical interventionGroup 2: suspicious, but not diagnosed appendicitis- benefit from imaging and 4-6h observation with surgical consult if serial exam changes or imaging studies confirm

DispositionGroup 3: remote possibility of appendicitis- observe in ED for serial exams; if no change and course remains benign patient can D/C with dx of nonspecific abd painPatients are given instructions to return if worsening of symptoms, and they should be seen by PCP in 12-24 hAlso advised to avoid strong analgesia

DispositionGroup 4: high risk population(including elderly, pediatric, pregnant and immunocomprimised)- require high index of suspicion and low threshold for imaging and surgical consultation

Ileitis, Colitis, and Diverticulitis

Crohn DiseaseChronic granulomatous inflammatory disease of the GI tract. Can involve any part of GI tract from mouth to anusIleum is involved in majority of casesConfined to colon in 20%Terms:regional enteritis, terminal ileitis, granulomatous ileocolitis

Crohn DiseaseEtiology and pathogenesis are unknown.Infectious, genetic, environmental factors have been implicated.Autoimmune destruction of mucosal cells as a result of cross-reactivity to antigens from enteric bacteria.

Crohn DiseaseCytokines,including IL and TNF have been implicated in perpetuating the inflammatory response.Anti-TNF(remicade) drugs have shown efficacy in treating Crohn disease

Crohn DiseaseEpidemiology: peak incidence is 15-22 years old with a second peak 55-66years20-30% increase in womenMore common in European 4 times more common in Jews than non-JewsMore common in whites vs blacks10-15% have family hx

Crohn DiseasePathology: most important is the involvement of all layers of the bowel and extension into mesenteric lymph nodesDisease has skip areas between involved areasLongitudinal deep ulcers and cobblestoning of mucosa are characteristicThese result in fissures, fistulas, and abscesses

Crohn DiseaseClinical features: variable and unpredictableAbd pain, anorexia, diarrhea, and weight loss are present in most cases1/3 of patients develop perianal fissures or fistulas, abscesses, or rectal prolapse

Crohn DiseasePatients may present with lat complications including:Obstruction, crampy abd pain, obstipation, intraabdominal abscess with fever10-20% have extraabdominal features such as: arthritis, uveitis, or liver diseaseCrohns should also be considered when evaluating FUO

Crohn DiseaseClinical course and manifestation depends of anatomic distribution.30% involves only small bowel, 30% only colon, and 50% involves both

Crohn DiseaseRecurrence rate is as high as 50% for those responding to medical managementRate is even higher for those requiring surgeryIncidence of hematochezia and perianal disease is higher when the colon is involved

Crohn DiseaseDermatologic complications: erythema nodosum and pyoderma gangrenosumOcular: episcleritis and uveitisHepatobiliary: pericholangitis, chronic hepatitis, primary sclerosing cholangitis, cholangiocarcinoma, pancreatitis, gallstones

Crohn DiseaseVascular: thromboembolic disease, vasculitis, arteritisOther: anemia, malnutrition, hyperoxaluria leading to nephrolithiasis, myeloplastic disease, osteomyelitis, osteonecrosis

Crohn DiseaseComplications: >75% of patients will require surgery within the first 20 years Abscesses present with pain and tenderness, but may also have palpable masses or fever spikesMost common fistula sites are between ileum and sigmoid colon, cecum, another ileal segment, or the skin

Crohn DiseaseFistulas should be suspected when there is a change in bowel movement frequency, amount of pain or weight lossGI bleed is common, but only 1% develop life threatening hemorrhage. Toxic megacolon occurs in 6% of patients and results massive GI bleed 50% of the time

Crohn DiseaseComplications can also arise from the treatment of the diseaseSulfasalazine, steroids, immunosuppressive agents, and antibiotics can cause leukopenia, thrombocytopenia, fever, infection, diarrhea, pancreatitis, renal insufficiency, liver failure.

Crohn DiseaseIncidence of malignancy is 3 times higher in Crohn disease than in general population

Crohn DiseaseDiagnosis: history, Upper GI, air-contrast barium enema and colonoscopyCharacteristic radiologic findings in small intestine include: segmental narrowing, destruction of normal mucosal pattern, and fistulas.

Crohn DiseaseColonoscopy is most sensitive for patients with colitisUseful for detecting mucosal lesions, defining extent of involvement, occurrence of colon ca. Abd CT is most useful for acute presentation

Crohn DiseaseFindings of bowel wall thickening, mesenteric edema, local abscess formation suggest Crohn disease.

Crohn DiseaseDifferential Dx: lymphoma, ileocecal amebiasis, sarcoidosis, deep chronic mycotic infections involving GI tract, GI TB, Kaposis sarcoma, campylobacter, Yersinia, ulcerative colitis, C.diff, ischemic colitis.

Crohn DiseaseTx: relief of symptoms, induction of remission, maintenance of remission, prevention of complications, optimizing timing of surgery, and maintenance of nutritionSince the disease is virtually incurable, emphasis should be placed of relief of symptoms and preventing complications

Crohn DiseaseInitial ED management: focus on severity of attack, identifying possible complications such as obstruction, hemorrhage, abscess, toxic megacolon.CBC, electrolytes, BUN/creatinine, and type and cross if appropriatePlain films may be useful for obstruction, perforation or toxic megacolon

Crohn DiseaseInitial Tx: NPO, IVF resuscitation and correction of electrolytesNG decompression if indicated, broad spectrum atbx(ampicillin or a cephalosporin, aminoglycoside, and flagyl) should be used for suspected fulminant colitis or peritonitis

Crohn DiseaseIV steroids: hydrocortisone 300mg qd, methylprednisone 48mg qd, or prednisolone 60mg qd should be used for severe diseaseSulfasalazine 3-4g qd can be effective for mild-moderate cases, although it has many toxic side effects

Crohn DiseaseOral steroids are reserved for severe disease-prednisone 40-60mg qdImmunosuppressive drugs: 6-MP or azathioprine are useful for steroid alternatives, healing fistulas, or in patients with contraindications to surgery Response to immunosuppressant agents takes 3-6 months

Crohn DiseaseFlagyl and Cipro have been shown some improvement in perianal complications and fistulous disease.Medically resistant or moderate cases may benefit from anti-TNF(Remicade) 5 mg/kg IVCellcept, etanercept, thalidomide, IL therapy may also be beneficial

Crohn DiseaseDiarrhea can be controlled using imodium, lomotil, or questran

Crohn DiseaseDisposition: patients with signs of fulminant colitis, peritonitis, obstruction, significant hemorrhage, dehydration, electrolyte/fluid imbalance should be hospitalized under the care of a surgeon or gastroenterologist

Crohn DiseasePatients with chronic disease can be discharged home as long as there are no serious complications.Alterations in maintenance therapy should be discussed with GIClose follow up should be secured.

Ulcerative ColitisChronic inflammatory disease of the colon. Inflammation is more severe from proximal to distal colonRectum is involved in nearly 100%Characteristic symptom is bloody diarrheaEtiology remains unknown

Ulcerative ColitisEpidemiology: similar to Crohn diseaseMore prevalent in US and northern Europe.First degree relatives have 15 fold increase for UC and 3.5 fold increase for Crohn disease

Ulcerative ColitisPathology: involves mucosa and submucosaMucosal inflammation and formation of crypt abscesses, epithelial necrosis, and mucosal ulcerationEarly stages mucosa membrane appears finely granular and friableSevere cases show large oozing ulcerations and pseudopolyps

Ulcerative ColitisClinical features:Mild:

Ulcerative ColitisModerate: manifesations are less severe and respond well to treatment. Typically have left sided colitis, but can have pancolitis.

Ulcerative ColitisCharacterized by: intermittent attacks of acute disease with remission between attacksUnfavorable prognosis and increased mortality is seen with higher severity and extent of disease, short interval between attacks, and onset of disease after 60

Ulcerative ColitisExtraintestinal complications: arthritis, ankylosing spondylitis, episcleritis, uveitis, pyoderma gangrenosum, erythema nodosum, liver disease(similar to that found in Crohn disease)

Ulcerative ColitisComplications: hemorrhage, toxic megacolon, perirectal abscesses and fistulas, colon ca, perforation

Ulcerative ColitisDx: lab findings are nonspecific. Diagnosis is made by Hx of abd cramps and diarrhea, mucoid stools, stool negative for ova/parasites, negative stool cultures confirmation of disease by colonoscopy showing granular, friable, ulceration of the mucosa, and sometimes pseudopolyps

Ulcerative ColitisDifferential Dx: similar to that of Crohn disease. Also be aware of STDs when confined to the rectum

Ulcerative ColitisTreatment: Severe UC: IV steroids, fluid replacement, electrolyte correction, broad spectrum atbx(amp and clindamycin or flagyl)Cyclosporine has been advocated for steroid refractory casesNG for toxic megacolon just as in crohn disease

Ulcerative ColitisMild to moderate: majority of cases can be treated as outpatient with daily prednisone 40-60mgActive proctitis, proctosigmoiditis, and left side colitis can be treated with 5-aminosalicylic acid enemas or topical steroid preparations

Ulcerative ColitisTreatment is very similar to Crohn diseaseOther supportive measures include metamucil or other bulking agentsAnti-diarrheals should be used with caution in case of toxic megacolon

Ulcerative ColitisDisposition:Fulminant attacks should be hospitalized for aggressive IVF and elctrolyte correction.Complications should be managed with appropriate surgical or GI consultMild-moderate: may be discharged with close follow up secured. Instructions on when to return should be given

Pseudomembranous ColitisInflammatory bowel disorder with membrane-like yellowish plaques of exudate overlie and replace necrotic intestinal mucosa

Pseudomembranous ColitisEpidemiology:Clostridium Difficile- spore forming obligate anaerobic bacillus3 types: neonatal, post-operative and antibiotic associatedRisk factors: recent atbx, GI surgery, severe medical illness, advancing ageTransmission: direct contact and objects

Pseudomembranous ColitisPathophysiology: 10-25% of hospital patients are colonizedDiarrhea in recently hospitalized person should suggest C.difficileBroad spectrum atbx such as clindamycin, cephalosporins, amp/amox- alter gut flora and allow C.difficile to flourishHowever any atbx can lead to C.difficile

Pseudomembranous ColitisC. difficile producestoxin A enterotoxintoxin B cytotoxinToxins interact and produce the colitis and associated symptoms

Pseudomembranous ColitisClinical features: from frequent mucoid, watery stools to profuse toxic diarrhea(>20-30 stools/day), abdominal pain, fever, leukocytosis, dehydration, hypovolemiaStool exam may reveal fecal leukocytes

Pseudomembranous ColitisComplications: severe electrolyte imbalance, hypotension, anasarca from low albumin, toxic megacolon, bowel perforationOnset is typically 7-10 days after starting atbx therapy

Pseudomembranous ColitisExtraintestinal complications are rare, but include: arthritis, visceral abscesses, cellulitis, necrotizing fasciitis, osteomyelitis, prostheitc device infection

Pseudomembranous ColitisDiagnosis: hx of diarrhea that develops during or within 2 weeks of atbx treatment.Confirmed by stool for C.difficile toxin and colonoscopyMost labs use ELISA to detect C.difficile toxins even though there are many other modes5-20% of patients require more than one stool to diagnose

Pseudomembranous ColitisTreatment: d/c atbx, supportive IVF, electrolyte correction, flagyl 250 mg qid, or vancomycin 125-250mg po qid(alternative regimen)25% of patients will respond to supportive measures onlySeverely ill patients should hospitalized

Pseudomembranous ColitisRelapses occur in 10-20% of patientsUse of anti-diarrheals should be avoidedSurgery or steroids are rarely needed

Pseudomembranous ColitisDisposition:Severe diarrhea, symptoms that persist despite outpatient management, or those with systemic response(fever, leukocytosis, severe abdominal pain) should be hospitalizedSuspected perforation, toxic megacolon or failure to respond to medical treatment need a surgical consult

Pseudomembranous ColitisFor patients who are discharged whom: good oral intake must be encouraged. Flagyl or vancomycin are equally effective for treatment.

DiverticulitisAcute inflammation of the wall of a diverticulum and surrounding tissueCaused by either a micro- or macroperforation

DiverticulitisEpidemiology: Acquire disease of the colon has become common in industrialized nationsApproximately 1/3 of population will acquire diverticuli by age 50 and 2/3 by age 85Rare

DiverticulitisDiverticulitis is estimated in 10-25% of people with known diverticulosisIncidence increases with ageOnly 2-4 % are < 40Diverticulitis in younger age is associated with more complications requiring surgical intervention

DiverticulitisFrequency is slightly higher in men, the incidence is on the rise in women

DiverticulitisPathophysiology:Cause is not knownLow residue diets have been implicatedAcute complications: Inflammation(and associated complications) and Bleeding

DiverticulitisInflammation is the most common complication of diverticulosisMechanism was thought to occur when fecal material was inspissated in the neck of a diverticulum, resulting in bacterial proliferation, mucous secretion, and distention

DiverticulitisMore commonly, it results from high pressure in the colon, erosion of diverticulum wall, microperforation, and inflammation.Free perforation can occur with generalized peritonitis, but is uncommon

DiverticulitisOther complications: obstruction and fistula formation between the bladder and diverticulum

DiverticulitisClinical Features: most common symptom is pain.Described as steady, deep discomfort in the LLQOther complaints: change in bowel habit, tenesmus, dysuria, frequency, UTI, distention, nausea, vomiting,

DiverticulitisPresentation may be indistinguishable for acute appendicitisDiverticulitis should always be considered in patient >50 with abdominal painPerforation is characterized by sudden lower abdominal pain progressing general abdominal pain

DiverticulitisPhysical exam: frequently fever of 38 C, localized abdominal tenderness, voluntary guarding, rebound, rectal tenderness on left side, possibly occult blood +, As always, Pelvic should be done with female Watch for signs of peritonitis or perforation

DiverticulitisDiagnosis: typically suspected by Hx and physicalAbdominal plain films can show partial SBO, free air, extraluminal airCT is procedure of choice. Demonstrates inflammation of pericolic fat, diverticula, thickening of bowel wall, peridiverticular abscess

DiverticulitisBarium enema can be done, but are insensitive and may cause perforation due to the introduction of barium at high pressuresRoutine labs include: CBC, electrolytes, BUN/creatinine, UASigmoidoscopy and colonoscopy are performed only after inflammation has decreased

DiverticulitisDifferential Dx:Similar to that of appendicititis, Crohn disease, UC, and C.difficile colitis

DiverticulitisTreatment:NPO, IVF, electrolyte correction, NG for obstruction, Broad spectrum atbx, observation for complicationsOutpatient management includes liquids only for 48 hours and oral antibiotics(Cipro, flagyl, bactrim, ampicillin)

DiverticulitisDisposition: Patients without signs of peritonitis or systemic infection maybe treated as outpatients with careful follow up arranged. Should be instructed to return for fever, increasing pain, unable to tolerate po.

DiverticulitisIf patient shows signs of systemic infection, perforation or peritonitis then they should be hospitalized with a surgical consult

Questions:1. With a retrocecal appendix, the pain of acute appendicitis may localize to the right flank. (True or false)2. Outpatient antibiotics is the standard treatment of acute appendicitis. (True or False)

Questions:3. Special populations of people that may have delayed diagnosis of acute appendicitis due to atypical presentation include:A.) very young patientsB.) elderly patientsC.) AIDS patientsD.) Pregnant patientsE.) all of the above

Questions:4. Crohn disease can involve:A.) any part of the GI tract(from mouth to anusB.) colon onlyC.) esophagus onlyD.) small intestine only

Questions:5. Ulcerative colitis and Crohn disease are both considered types of inflammatory bowel disease. (True or False)

Answers: 1T, 2F, 3E, 4A, 5T