Surgical pathology of the appendix

Acute appendicitisChronic appendicitisTumors of the appendix

Appendix

Functions – not clear in humans- it may have a significance in immune defense – abundance of lymphoid follicles

- removal of the appendix may be a cause for an increase in colonic cancer incidence - not supported by controlled studies

- endocrine function

“Normal” Anatomy

Typical position

2.5 cm bellow the ileo-cecal valve (base of appendix) the only fix region – important when trying to find the appendixTaeniae converge at the base of the appendix84% free mobile in any possible location16% fixed retrocecal

Acute apendicitis

Essentials of diagnosisAbdominal painAnorexia, nausea, vomitingLocalized abdominal tendernessLow grade feverLeukocytosis

General considerations= acute inflammation of the appendix wall that starts in the mucosa and may extend to adjacent organs

70% of cases present obstruction of the proximal lumen: Fibrous bands, fecaliths, foreign bodies Tumors, parasites, lymphoid hyperplasia External compression

Inflammation starts in the mucosa with ulcerations and secondary bacterial infection

Close tube

Blood supply affected as disease progresses Infection in the wall Increased pressure

Puss formation inside the lumenWall destruction: gangrene + perforationBacterial peritonitis may be limited by adhesions (plastic peritonitis)

Clinical findings

Protean manifestation: may mimic a variety of conditions

Progression of symptoms is essential

Clinical findings

Onset: vague abdominal discomfortFollowed: Nausea, anorexia, indigestionVomitingPain, mild, localized in the epigastrum

Pain: localized in RLQ +Pain or discomfort (moving, walking,

coughing)

Examination

At this moment:Tenderness on coughing, localized in RLQLocalized tenderness on palpation Slight muscular rigidityRebound tenderness referred to the same

areaRectal and pelvic examination NORMALLow fever (<38 degrees)

Examination – retrocecal appendicitis

Poorly localized pain (retrocecal position – protected from the abdominal wall)

No discomfort on coughing, walking etc.

Diarrhea

Urinary symptoms (hematuria, urinary frequency)

Pain in the flank – tenderness on one finger examination

Examination – pelvic appendicitis

May simulate gastroenteritis

Nausea, vomiting and diarrhea are more prominent (adjacent appendix to pelvic colon)

Negative abdominal examination

IMPORTANT – repeated pelvic (rectal) examination

Aberrant positions

Left side appendix – confusion with diverticulitis (malrotation)

RUQ – cecum in abnormal position may mimic cholecystitis or perforated duodenal ulcer

Normal cecum – long appendix – anything is possible

Lab workupHigh leukocyte count: average 15.000/μl, 90% more the 10.000 with more then 75% neutrophils.10% have normal formula

Urinalysis typically normal, few leukocytes or eritrocytes. Retrocecal or pelvic – special attention

X-Ray findings

Plain X-Ray films are usually not contributory Air-fluid levels or isolated ileusFecalithsFree air in the peritoneumSigns of peritonitis

CT scan

Ultrasound scan

Appendicitis in pregnancy

Same frequency as in non-pregnant

Difficult diagnosisHigh position of the appendixAll usual signs are presentDifficult to interpret leukocytosis

Appendectomy is mandatory and urgent

Differential diagnosis

Differential diagnosis

Difficult in young and elderly – highest incidence of perforation

High incidence of false positive appendicitis: women 20-40 PID and other genital conditions

Differential diagnosis

Local inflammatory conditions (enterocolitis, urinary infections, urinary stones, pelvic inflammatory disease)Distant digestive diseases (compliacted duodenal ulcer, billiary stones) Distant non-digestive diseases (penumonia, myocardial infarction, porphyria, lead poisoning)

Complications

PERFORATIONMore severe painFever >38Typically in the first 12 hours In 50% of patients the appendix is

perforated at the time of diagnosis

Complications

PERITONITISLocalized – microscopic perforation Increased tenderness, rigidity Abdominal distension Ileus Fever high and toxicity Douglas pouch very sensible

Generalized – classic presentation

Complications

APPENDICEAL ABSCESS (appendiceal mass)Localized peritonitisWalled off by peritoneumSymptoms of appendicitis + mass in RLQUS + CT characteristical

Complications

APPENDICEAL ABSCESSTreatment: ATB + diet low in residueDrainage of abscess +/- appendectomyPostponed appendectomy 8-12 weeks

Differential diagnosis:Carcinoma of the cecumTumors of the appendixGenital pathology

Complications

Pylephlebitis: suppurative thrombophlebitis of pportal veinChills, high fever, jaundice + hepatic

abscess formation.Serious septic problems

CT scan + US: thrombosis and gas in portal systemTreatment: ATB + surgery urgent

Treatment

CHRONIC APPENDICITIS

Chronic abdominal pain

In the RLQ

Possible recurrent attack of acute appendicitis

Other problems

Many do not consider chronic appendicitis a reality

= chronic inflammation in the wall due to multiple acute attacks

Pathology – retractions of appendix and mesoappendix and adhesions

Examination – dispepsia + pain

Workup – to exclude another pathology

Tratament – appendectomy - debatable

Chronic appendicitis

Tumors of the appendix

Classification

Benign – fibroma

- leyomioma

- lypoma

Malignant – carcinoma

Bordeline - carcinoid

- mucocele

Benign tumors

Very rare

Occasionally may obstruct the lumen and cause acute apendicitis

May arise as a mass in RLQ

Carcinoma Rare and never diagnosed preoperativelyMost typical presents as acute appendicitis or RLQ abscessPrognosis: bad – 10% wide spread MTS at time of diagnosis. Rapid lymph node spread and local spread through peritoneal cavity (ovary)Treatment: right hemicolectomy + lymph node dissection

Carcinoid tumor

The most common location of carcinoid in the digestive tractSlow growth (<2 cm) and rarely MTS. 3% MTS in lymph nodesCarcinoid sdr: attacks of vasodilation, diarrhea, abdominal colical pain, tachicardia, hipotension MTSMTSExamination: RLQ pain + mass

Carcinoid

Lab workup:Urinary 5HIAUS, CT, arteriography, bronchoscopy

Treatment:AppendectomyRight hemicolectomy (>2cm, invasion of

cecum, invasion mesoappendix, nodes)MTS – enucleation (<4) +/or chemotherapy

Mucocele

Not true tumors:Chronic distension of the appendix plus continuous

mucus secretion. Flattened epithelial cellsCystadenoma – columnar epithelium (low grade

adenocarcinoma). Do not infiltrate the wall and do not produce MTS

Clinical examination:RLQ discomfortMassRupture in peritoneum: pseudomixoma peritonei

MucoceleTreatment: appendectomy

MUCINOUS CHIST-ADENOMA - APENDICULARMUCINOUS CHIST-ADENOMA - APENDICULAR