AppendicitisAppendicitis

by Chanda McDaniel by Chanda McDaniel 1/081/08

ObjectivesObjectives

To review 3 cases of appendicitis (that To review 3 cases of appendicitis (that presented to AUCC at DH)presented to AUCC at DH)

To discuss how we could improve the To discuss how we could improve the care of these patientscare of these patients

To review the presentation, work-up, To review the presentation, work-up, and differential diagnosis of and differential diagnosis of appendicitisappendicitis

Case 1 HPICase 1 HPI

37yo female presents to PCP (seen 37yo female presents to PCP (seen by resident) for 6 wk postpartum by resident) for 6 wk postpartum check up with abdominal pain x 5-7 check up with abdominal pain x 5-7 days.days.

No N/V. Pain is achy/diffuse. Subjective No N/V. Pain is achy/diffuse. Subjective fever yesterday.fever yesterday.

No appetite. Drinking. Nl BMs. No No appetite. Drinking. Nl BMs. No dysuria or abnormal vaginal discharge. dysuria or abnormal vaginal discharge. Stopped bleeding 1 ½ weeks ago. Stopped bleeding 1 ½ weeks ago.

Case 1 PhysicalCase 1 Physical

37.5 128 124/81 2237.5 128 124/81 22NADNADH - RRR w/o MH - RRR w/o MA - TTP midline, RLQ, LLQ, NABS, soft, A - TTP midline, RLQ, LLQ, NABS, soft,

non-distended, + guardingnon-distended, + guardingPelvic - midline tenderness, no Pelvic - midline tenderness, no

adnexal tenderness, no foul-smelling adnexal tenderness, no foul-smelling dischargedischarge

Case 1 LabsCase 1 Labs

U/A-1.025, pH 5, 1+pro, 1+Hgb, 1-5 U/A-1.025, pH 5, 1+pro, 1+Hgb, 1-5 WBCs, 6-10 RBCsWBCs, 6-10 RBCs

UHCG - negativeUHCG - negative

Case 1 PCP Dx, PlanCase 1 PCP Dx, Plan

Late postpartum endometritisLate postpartum endometritisDoxycycline 100mg po BID x 14 daysDoxycycline 100mg po BID x 14 daysVicodin, Colace, IbuprofenVicodin, Colace, IbuprofenRTC 1 weekRTC 1 week

3 days later3 days later

Pt presents to AUCC with worsening Pt presents to AUCC with worsening abdominal and low back pain.abdominal and low back pain.

Dizzy. Decreased appetite. Fever. Pain Dizzy. Decreased appetite. Fever. Pain 5/10. Nausea x 1 wk.5/10. Nausea x 1 wk.

No emesis, diarrhea, dysuria, vaginal No emesis, diarrhea, dysuria, vaginal discharge or URI sxs. discharge or URI sxs.

AUCC PhysicalAUCC Physical

38.3 113 16 113/70 99% RA38.3 113 16 113/70 99% RAHEENT – pale conjunctiva, nl o/pHEENT – pale conjunctiva, nl o/pH – RRR w/o M (90)H – RRR w/o M (90)L – CTABL – CTABA – NABS, soft, tender in suprapubic A – NABS, soft, tender in suprapubic

area, less in RLQ, no rebound, no area, less in RLQ, no rebound, no obturator or psoas signobturator or psoas sign

GU – no CMT, min. discharge, uterus GU – no CMT, min. discharge, uterus TTPTTP

AUCC Labs/xrayAUCC Labs/xray

UA – 1-5 WBC, 1-5 RBC, 1+ bacteriaUA – 1-5 WBC, 1-5 RBC, 1+ bacteriaWBC 12.6, Hb 12.5, Hct 38.9, plts 323WBC 12.6, Hb 12.5, Hct 38.9, plts 323Chem 7 – nl, Calcium – nlChem 7 – nl, Calcium – nlPelvic US – nlPelvic US – nlCT – 9.6x7cm mass abuts cecum with CT – 9.6x7cm mass abuts cecum with

surrounding fat stranding most likely surrounding fat stranding most likely perforated appendicitis with perforated appendicitis with associated abscessassociated abscess

AUCC courseAUCC course

Pt seen by surgery who wanted to admit & Pt seen by surgery who wanted to admit & take pt to OR. She refused and left AMA, take pt to OR. She refused and left AMA, but said she would return in AM.but said she would return in AM.

Pt returned the next day and said that she Pt returned the next day and said that she refused admission due to a religious refused admission due to a religious holiday and was admitted to surgery. holiday and was admitted to surgery.

She was discharged on Levo and Flagyl She was discharged on Levo and Flagyl post op.post op.

EndometritisEndometritis

Most cases develop within the 1st week Most cases develop within the 1st week after deliveryafter delivery

15% present between 1-6 weeks 15% present between 1-6 weeks postpartumpostpartum

May present as late postpartum May present as late postpartum hemorrhage hemorrhage

Clinical criteria Clinical criteria Fever and uterine tenderness occurring in a Fever and uterine tenderness occurring in a

postpartum woman postpartum woman foul lochia, chills, and lower abdominal pain foul lochia, chills, and lower abdominal pain

Admit for IV antibiotics (Clinda/Gent)Admit for IV antibiotics (Clinda/Gent)

What could we (at DH) have What could we (at DH) have done differently?done differently?

PCP could have considered appendicitis in PCP could have considered appendicitis in the differentialthe differential

Pt presentation was atypical for endometritisPt presentation was atypical for endometritis Late onsetLate onset No VB or dischargeNo VB or discharge

Abnormal vitals (HR 128) not addressedAbnormal vitals (HR 128) not addressed No labs were drawn (even for baseline)No labs were drawn (even for baseline) Needed admission/IV Abx (?), if diagnosis of Needed admission/IV Abx (?), if diagnosis of

endometritis was correctendometritis was correct

Case 2 HPICase 2 HPI

21 yo female presents with abd. pain 21 yo female presents with abd. pain and vaginal bleeding x 3 days. and vaginal bleeding x 3 days.

Not using pad – just on TP. Not using pad – just on TP. Recently had IUD removed. Recently had IUD removed. No N/V.No N/V.PMH – DepressionPMH – DepressionMeds – ProzacMeds – ProzacNKDANKDA

Case 2 PhysicalCase 2 Physical

36.3 119 110/63 1836.3 119 110/63 18NADNADChest – clearChest – clearH – RRH – RRA – soft, marked tenderness in RLQ, A – soft, marked tenderness in RLQ,

tender in suprapubic area & LLQ, no tender in suprapubic area & LLQ, no rebound, NABSrebound, NABS

Pelvic – blood in vault, cervix/uterus Pelvic – blood in vault, cervix/uterus tender, adnexa tender R>Ltender, adnexa tender R>L

Case 2 LabsCase 2 Labs

UA – mod ketones, 1.015, 2+pro, tr blood, UA – mod ketones, 1.015, 2+pro, tr blood,

tr leu, 11-20 WBC, no RBC, 1+crystalstr leu, 11-20 WBC, no RBC, 1+crystals

UHCG – negativeUHCG – negative

CBC – WBC 26.6, hb 14.9, hct 42.9, plt CBC – WBC 26.6, hb 14.9, hct 42.9, plt

406, 87% segs 406, 87% segs

Chem 7 normal except Na 133Chem 7 normal except Na 133

Case 2 Dx & PlanCase 2 Dx & Plan

Abdominal pain with elev. WBCs, Abdominal pain with elev. WBCs, some WBCs in urinesome WBCs in urine

R/O PID vs UTI, doubt appyR/O PID vs UTI, doubt appyUrine cx PUrine cx PGonorrhea/Chlamydia PGonorrhea/Chlamydia PLevofloxacin 500mg BID, Flagyl Levofloxacin 500mg BID, Flagyl

500mg BID x 14 days500mg BID x 14 days

Case 2 AUCC f/uCase 2 AUCC f/u

Seen 1 day later in AUCC – “Pt did not Seen 1 day later in AUCC – “Pt did not want CT yesterday. Feels better.” Meds want CT yesterday. Feels better.” Meds upset stomach. Ate some breakfast. No upset stomach. Ate some breakfast. No nausea now. nausea now.

VS 38.4 113/69 124 20VS 38.4 113/69 124 20A - +BS, soft, tender in RLQ w/ guardingA - +BS, soft, tender in RLQ w/ guardingWBC 20.7, Hb 13.7, Hct 40.2, Plts 333WBC 20.7, Hb 13.7, Hct 40.2, Plts 333CT – RLQ 11x4cm abscess, adj to cecumCT – RLQ 11x4cm abscess, adj to cecum

Case 2 Hosp. courseCase 2 Hosp. course

Pt admitted for perforated appendix Pt admitted for perforated appendix (approximately 7-10 days old) and (approximately 7-10 days old) and placed on IV Timentin. placed on IV Timentin.

IR placed drain on hosp. day 1 and IR placed drain on hosp. day 1 and removed on day 7 after 2removed on day 7 after 2ndnd CT scan CT scan (although I can’t find the report of 2(although I can’t find the report of 2ndnd CT). CT).

Discharged on Augmentin, Colace, Discharged on Augmentin, Colace, Vicodin. Vicodin.

What could we have done What could we have done differently?differently?

If appendicitis was in the differential If appendicitis was in the differential and it was not visualized on US and it was not visualized on US consider CT or surgery consult.consider CT or surgery consult.

If patient refused CT, we could have If patient refused CT, we could have improved our documentation on her improved our documentation on her initial visit.initial visit.

Case 3 HPICase 3 HPI

51 yo male with epigastric pain since 51 yo male with epigastric pain since this am. N/V x 3. No diarrhea. No this am. N/V x 3. No diarrhea. No fever.fever.

PMH – No hospitalizations.PMH – No hospitalizations.Meds – Tylenol fluMeds – Tylenol fluAll – noneAll – noneSHx – no exposures, ETOH yesterdaySHx – no exposures, ETOH yesterday

Case 3 PhysicalCase 3 Physical

36.7 142/85 66 20 (not orthostatic)36.7 142/85 66 20 (not orthostatic) General - Alert, NADGeneral - Alert, NAD HEENT – NCAT, anicteric, o/p -, neck HEENT – NCAT, anicteric, o/p -, neck

supple w/o LADsupple w/o LAD H – RRR w/o mH – RRR w/o m L – CTABL – CTAB A – NABS, soft, mild epigastric tenderness A – NABS, soft, mild epigastric tenderness

to palpation, more TTP in RLQ, + rebound, to palpation, more TTP in RLQ, + rebound, - heel tap, - obturator, + psoas, nl rectal- heel tap, - obturator, + psoas, nl rectal

Case 3 LabsCase 3 Labs

WBC 16.4, Hb 16.1, Hct 47.8, Plts WBC 16.4, Hb 16.1, Hct 47.8, Plts 221, 91% Segs221, 91% Segs

Chem 7 – normalChem 7 – normalLFT’s – normalLFT’s – normalAmylase – 27Amylase – 27U/A – 1.038, 2+pro, 1+Hb, 2+glc, - U/A – 1.038, 2+pro, 1+Hb, 2+glc, -

WBC, - RBCWBC, - RBCGuaiac - negativeGuaiac - negative

Case 3 CTCase 3 CT

Verbal report – Equivocal for Verbal report – Equivocal for appendicitisappendicitis

Written report – There is considerable Written report – There is considerable fecal material within the cecum, but fecal material within the cecum, but the terminal ileum is not dilated and the terminal ileum is not dilated and the appendix is normal. Moderate the appendix is normal. Moderate thickening of sigmoid colon, which may thickening of sigmoid colon, which may indicate a prior inflammatory process. indicate a prior inflammatory process. No evidence of acute diverticulitis. No evidence of acute diverticulitis.

Case 3 Surgery ConsultCase 3 Surgery Consult

51 yo w/ epigastric pain – better now. 51 yo w/ epigastric pain – better now. N/V x 1. N/V x 1.

A – NTTPA – NTTPCT – poorly visualized appendixCT – poorly visualized appendixA/P – resolved Abd pain, with elevated A/P – resolved Abd pain, with elevated

WBC. Would like to admit for obs, but WBC. Would like to admit for obs, but pt would like to go home. Return to pt would like to go home. Return to AUCC in am for recheck, CBC. AUCC in am for recheck, CBC.

Case 3 AUCC f/uCase 3 AUCC f/u

51 yo w/ abd pain seen yesterday. N/V 51 yo w/ abd pain seen yesterday. N/V x2 this am. Constant pain. No appetite. x2 this am. Constant pain. No appetite.

37.3 64 20 128/7437.3 64 20 128/74A – RLQ tendernessA – RLQ tendernessWBC 20.3, Hb 15.7, Hct 46, plts 225, WBC 20.3, Hb 15.7, Hct 46, plts 225,

87S87SAdmitted to surgery. Laproscopic eval –Admitted to surgery. Laproscopic eval –

> partially necrotic appendix (ruptured > partially necrotic appendix (ruptured per path) per path) open appendectomy. open appendectomy. Discharged on Levo/Flagyl. Discharged on Levo/Flagyl.

What could we have done What could we have done differently?differently?

Talked pt into staying the night in the Talked pt into staying the night in the hospital? This may have prevented hospital? This may have prevented rupture?rupture?

Appendicitis EpidemiologyAppendicitis Epidemiology

250,000 cases/yr in US250,000 cases/yr in US most common in 2most common in 2ndnd/3/3rdrd decades of life decades of life highest incidence in 10-19 yo age grouphighest incidence in 10-19 yo age group no age is exemptno age is exempt males > femalesmales > females rate of negative appendectomies (15-20%) rate of negative appendectomies (15-20%)

has not declined in the last 15 years has not declined in the last 15 years despite the increasing use of US and CTdespite the increasing use of US and CT DH: 1-2 carcinoids, 2-3 parasitic infections, TB, TOA/several DH: 1-2 carcinoids, 2-3 parasitic infections, TB, TOA/several

hundred surgeries (<1%)hundred surgeries (<1%)

Mortality <1% (nonperf)Mortality <1% (nonperf) > ,> ,5%5% ( )perf ( )perf

PathophysiologyPathophysiology

1) Obstruction of lumen1) Obstruction of lumenyoung = lymphoid follicular hyperplasia young = lymphoid follicular hyperplasia

(due to viral or bacterial infection and (due to viral or bacterial infection and dehydration)dehydration)

older = fibrosis, fecalith, neoplasmolder = fibrosis, fecalith, neoplasm2) Fills with mucus2) Fills with mucusdistendsdistendsincreases increases

intraluminal pressureintraluminal pressurethrombosisthrombosis ischemiaischemianecrosis (<24hrs) and necrosis (<24hrs) and perforation (>48hrs)perforation (>48hrs)

OrganismsOrganisms

E. coliE. coliPeptostreptococcusPeptostreptococcusBacteriodes FragilisBacteriodes FragilisPseudomonasPseudomonas

Appendix AnatomyAppendix Anatomy

normal = lies in RLQnormal = lies in RLQ

retrocecal (65%)retrocecal (65%)

pelvic (30%)pelvic (30%)

intestinal malrotation = LUQintestinal malrotation = LUQ

pregnant = RUQpregnant = RUQ

SymptomsSymptoms Initial Initial

indigestionindigestion flatulenceflatulence bowel irregularitybowel irregularity

Epigastric or periumbilical painEpigastric or periumbilical pain visceral - constant, not very severe in intensity, visceral - constant, not very severe in intensity,

poorly localizablepoorly localizable Then, N/V (not usually 1Then, N/V (not usually 1stst symptoms) symptoms) Fever (higher suggests perf)Fever (higher suggests perf) Sxs may subside (temporarily) after ruptureSxs may subside (temporarily) after rupture

Abdominal PainAbdominal Pain

VisceralVisceral

ParietalParietal

ReferredReferred

Visceral painVisceral pain

Stretching, distention, torsion, or contraction of Stretching, distention, torsion, or contraction of abdominal organsabdominal organs

Carried on slow-conducting fibersCarried on slow-conducting fibers Dull acheDull ache Location correspond to dermatomes that Location correspond to dermatomes that

match the innervation of the injured organmatch the innervation of the injured organEpigastriumEpigastrium organs proximal to ligament of treitz organs proximal to ligament of treitz

(hepatobiliary, spleen)(hepatobiliary, spleen)PeriumbilicalPeriumbilicalligament of treitz to hepatic flexure of ligament of treitz to hepatic flexure of

coloncolonMidline lower abdMidline lower abdorgans distal to hepatic flexureorgans distal to hepatic flexure

Parietal PainParietal Pain

Well-localizedWell-localizedResults from direct irritation of the Results from direct irritation of the

peritoneal liningperitoneal liningA delta fibersA delta fibersrapid conductionrapid conductionSharp pain sensationSharp pain sensation

Referred painReferred pain

Occurs when visceral afferents carrying Occurs when visceral afferents carrying stimuli from a diseased organ enter the stimuli from a diseased organ enter the spinal cord at the same level as spinal cord at the same level as somatic afferents from a remote somatic afferents from a remote anatomic location.anatomic location.

Typically well-localizedTypically well-localizedGall bladder inflammation to R shoulderGall bladder inflammation to R shoulderDiaphragmatic rupture to shoulderDiaphragmatic rupture to shoulderHeart attack to L armHeart attack to L arm

Physical Exam: AppendicitisPhysical Exam: Appendicitis Pain is subjectivePain is subjective Tenderness is objective; Tenderness is objective;

local tenderness in RLQlocal tenderness in RLQ McBurney’s point (1/3 of McBurney’s point (1/3 of

distance of line from distance of line from anterior iliac spine to anterior iliac spine to umbilicus) umbilicus)

May have tenderness in May have tenderness in RLQ during rectal and RLQ during rectal and pelvicpelvic

Common Signs of Appendicitis• Right lower quadrant pain on palpation (the single most important sign)• Low-grade fever (38°C [or 100.4°F])--absence of fever or high fever can occur• Peritoneal signs• Localized tenderness to percussion• Guarding• Other confirmatory peritoneal signs (absence of these signs does not exclude appendicitis)• Psoas sign--pain on extension of right thigh (retroperitoneal retrocecal appendix)• Obturator sign--pain on internal rotation of right thigh (pelvic appendix)• Rovsing's sign--pain in right lower quadrant with Rovsing's sign--pain in right lower quadrant with palpation of left lower quadrantpalpation of left lower quadrant• • Dunphy's sign--increased pain with coughingDunphy's sign--increased pain with coughing• Flank tenderness in right lower quadrant (retroperitoneal retrocecal appendix)• Patient maintains hip flexion with knees drawn up for comfort

3 PE findings with highest 3 PE findings with highest predictive value of predictive value of

appendicitisappendicitis1) RLQ pain1) RLQ pain2) Abdominal rigidity2) Abdominal rigidity3) Migration of a pain from 3) Migration of a pain from

periumbilical region to the RLQperiumbilical region to the RLQ

Occur in about 50% of patientsOccur in about 50% of patients

Retrocecal appendixRetrocecal appendixAppendix Appendix

doesn't doesn't touch touch parietal parietal peritoneumperitoneum

Sxs Sxs not not

localizedlocalizeddull achedull ache+psoas sign+psoas signflank painflank pain

Psoas signPsoas sign

Inflamed appx is Inflamed appx is in retroperitoneal in retroperitoneal location in location in contact with contact with psoaspsoas

Pelvic AppendixPelvic Appendix

May have no abdominal signsMay have no abdominal signsUrinary frequencyUrinary frequencyDysuriaDysuriaTenesmusTenesmusDiarrheaDiarrheaTenderness with rectal examTenderness with rectal examPositive obturator signPositive obturator sign

Obturator signObturator sign

Inflamed appx is Inflamed appx is in pelvis, in in pelvis, in contact with contact with obturator muscleobturator muscle

LabsLabsUAUA

r/o UTI (micro hematuria/pyuria in 30% appys)r/o UTI (micro hematuria/pyuria in 30% appys) >30 RBC or >20 WBC ->30 RBC or >20 WBC - urinary urinary

UHCGUHCG r/o ectopicr/o ectopic

Pelvic culturesPelvic cultures CBCCBC

leukocytosisleukocytosis 30% have normal WBC (95% have left shift)30% have normal WBC (95% have left shift)

Radiology (CT or US)Radiology (CT or US)

Obtain if diagnosis is unclear.Obtain if diagnosis is unclear.A population based study suggested A population based study suggested

that the rates of negative that the rates of negative appendectomies have not changed appendectomies have not changed between 1980 and 1999.between 1980 and 1999.

CT AppyCT Appy

Sensitivity 94%Sensitivity 94% Specifity 95%Specifity 95% Air or contrast in appendix – excludes dxAir or contrast in appendix – excludes dx Diameter 6 mm or less - normalDiameter 6 mm or less - normal Non-visualized appxNon-visualized appx

does not rule out appendicitisdoes not rule out appendicitis

If pt with sxs for a short duration, only min. If pt with sxs for a short duration, only min. inflammation may be presentinflammation may be present

IV contrast (?)IV contrast (?) - - may improve wall appearance/inflammationmay improve wall appearance/inflammation

Normal Appendix on CTNormal Appendix on CT

Appendicitis on CTAppendicitis on CT

Dm >6mmDm >6mmAppendicolithAppendicolithCecal thickeningCecal thickeningArrowhead signArrowhead sign

abscess abscess formationformation

cecal thickeningcecal thickening

Arrowhead signArrowhead sign

An axial CT image in the upper pelvis shows edema of the cecal wall which, along with barium in the cecum (C), contributes to the "arrowhead sign" of appendicitis. A dilated fluid filled appendix (large arrow) is seen with adjacent stranding of retroperitoneal fat (arrowheads). The appendix follows a retrocecal course (small arrows).

CT radiationCT radiation

““There is direct evidence from There is direct evidence from epidemiologic studies that the organ epidemiologic studies that the organ doses corresponding to a common CT doses corresponding to a common CT study (2-3 scans, dose 30-90 mSv) result study (2-3 scans, dose 30-90 mSv) result in an increased risk of cancer.”in an increased risk of cancer.”

10,000 adults, 35 yrs old, US instead of CT10,000 adults, 35 yrs old, US instead of CTAppendicitis would be missed in 480 casesAppendicitis would be missed in 480 cases2 patients could be prevented from 2 patients could be prevented from

developing cancer in the futuredeveloping cancer in the future

Differential DiagnosisDifferential Diagnosis

Cecal diverticulitisCecal diverticulitis Meckel's diverticulitisMeckel's diverticulitis Ilietis (bacterial infection)Ilietis (bacterial infection)

YersiniaYersinia CampylobacterCampylobacter SalmonellaSalmonella Crohn'sCrohn's

PIDPID Ob/GynOb/Gyn UTI/NephrolithiasisUTI/Nephrolithiasis

TreatmentTreatment

NPONPOIVFIVFAntibioticsAntibiotics

nonperforated preop – Cefazolin, Flagyl, nonperforated preop – Cefazolin, Flagyl, (Timentin or Cefotetan at DH)(Timentin or Cefotetan at DH)

perforated – Levo + Flagyl (x 7-10 days) perforated – Levo + Flagyl (x 7-10 days)

BibliographyBibliography 1) 1) Brenner, D. Computed Tomography – An Increasing Source of Brenner, D. Computed Tomography – An Increasing Source of

Radiation Exposure. NEJM. Nov. 2oo7;2277-84.Radiation Exposure. NEJM. Nov. 2oo7;2277-84.

2) Doria, A. US or CT for diagnosis of appendicitis in Children and 2) Doria, A. US or CT for diagnosis of appendicitis in Children and adults? A meta-analysis. Radiology. Aug. 2006:241:83-94.adults? A meta-analysis. Radiology. Aug. 2006:241:83-94.

3) Flaser, M. Acute Abdominal Pain. Medical Clinics of North 3) Flaser, M. Acute Abdominal Pain. Medical Clinics of North America. May 2006:90;3.America. May 2006:90;3.

4) Goldberg, J. Appendicitis in adults. Uptodate. August 2007.4) Goldberg, J. Appendicitis in adults. Uptodate. August 2007.

5) Hardin, M. Acute appendicitis: Review and Update. American 5) Hardin, M. Acute appendicitis: Review and Update. American Family Physician 1999;60:2027-2034.Family Physician 1999;60:2027-2034.

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