Surgical pathology of the appendix Acute appendicitis Chronic appendicitis Tumors 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 appendix Taeniae converge at the base of the appendix 84% free mobile in any possible location 16% fixed retrocecal

Acute apendicitis Essentials of diagnosis Abdominal pain Anorexia, nausea, vomiting Localized abdominal tenderness Low grade fever Leukocytosis

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 lumen Wall destruction: gangrene + perforation Bacterial 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 discomfort Followed: Nausea, anorexia, indigestion Vomiting Pain, mild, localized in the epigastrum Pain: localized in RLQ + Pain or discomfort (moving, walking, coughing)

Examination At this moment: Tenderness on coughing, localized in RLQ Localized tenderness on palpation Slight muscular rigidity Rebound tenderness referred to the same area Rectal and pelvic examination NORMAL Low 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 workup High 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 ileus Fecaliths Free air in the peritoneum Signs of peritonitis

CT scan

Ultrasound scan

Appendicitis in pregnancy Same frequency as in non-pregnant Difficult diagnosis High position of the appendix All usual signs are present Difficult 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 PERFORATION More severe pain Fever >38 Typically in the first 12 hours In 50% of patients the appendix is perforated at the time of diagnosis

Complications PERITONITIS Localized – 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 peritonitis Walled off by peritoneum Symptoms of appendicitis + mass in RLQ US + CT characteristical

Complications APPENDICEAL ABSCESS Differential diagnosis: Treatment: ATB + diet low in residue Drainage of abscess +/- appendectomy Postponed appendectomy 8-12 weeks Differential diagnosis: Carcinoma of the cecum Tumors of the appendix Genital pathology

Complications Pylephlebitis: suppurative thrombophlebitis of pportal vein Chills, high fever, jaundice + hepatic abscess formation. Serious septic problems CT scan + US: thrombosis and gas in portal system Treatment: 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 appendicitis = 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

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 preoperatively Most typical presents as acute appendicitis or RLQ abscess Prognosis: 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 tract Slow growth (<2 cm) and rarely MTS. 3% MTS in lymph nodes Carcinoid sdr: attacks of vasodilation, diarrhea, abdominal colical pain, tachicardia, hipotension MTS Examination: RLQ pain + mass

Carcinoid Lab workup: Treatment: Urinary 5HIA US, CT, arteriography, bronchoscopy Treatment: Appendectomy Right hemicolectomy (>2cm, invasion of cecum, invasion mesoappendix, nodes) MTS – enucleation (<4) +/or chemotherapy

Mucocele Not true tumors: Clinical examination: Chronic distension of the appendix plus continuous mucus secretion. Flattened epithelial cells Cystadenoma – columnar epithelium (low grade adenocarcinoma). Do not infiltrate the wall and do not produce MTS Clinical examination: RLQ discomfort Mass Rupture in peritoneum: pseudomixoma peritonei

Mucocele Treatment: appendectomy

MUCINOUS CHIST-ADENOMA - APENDICULAR