LECTURE 3

Acute appendicitis

National O. Bogomolets Medical University

Faculty Surgery Department N1Kyiv 2007

Prof. Kucher M.

Appendicitis is an inflammation of the appendix

• Appendicitis remains the most common acute surgical condition of the abdomen.

• The overall lifetime occurrence is approximately 12 % in men and 25 % in women

Historical aspects

• Appendicitis was first recognized as a disease entity in 1886 by Reginald H.Fitz, Professor of Pathologic Anatomy at Harvard

• Charles Mc Burney described the clinical findings of early acute appendicitis (prior to rupture) in 1889

• Incision actually was devised by McArthur 1884,

• M. Volkovich, 1898

Etiology remains unclear; viral infection is suggested to be an etiological agent

(concurrent viral illness & seasonal variation in the incidence)

Pathogenesis obstruction is though to play the main role in the initiation

of inflammation:• Fecaliths, lymphoid hyperplasia, foreign bodies, carcinoid tumors,

strictures

• Inflammation of the wall of the appendix causes venous congestion, which may compromise arterial inflow, leading to ischemia and infarction. Microorganisms from the lumen of the appendix enter the submucosa through an ischaemic ulcer, causing liquefaction of the wall and ultimately perforation

• Primary ischemia (in older people)

Pathogenesis (cont.)

Various specific bacteria, viruses, fungi, and parasites can be responsible agents of infection that affect the appendix, including

Yersinia species, adenovirus, cytomegalovirus, actinomycosis, Mycobacteria species, Histoplasma species, Schistosoma species, pinworms, and Strongyloides stercoralis

Pathogenesis (cont.)

Within a few hours, this localized condition may worsen because of thrombosis of the appendicular artery and veins, leading to perforation and gangrene of the appendix. As this process continues, a periappendicular abscess or peritonitis may occur

Classification (1)

Staging: Appendicitis usually has 3 stages.

• Edematous stage– Appendicitis may have spontaneous regression or may evolve to

the second stage.– The mesoappendix is commonly involved with inflammation.

• Purulent (phlegmonous) stage– Spontaneous regression rarely occurs.– Appendicitis usually evolves beyond perforation and rupture.– Peritonitis may be possible.

• Gangrenous stage– Spontaneous regression never occurs.– Peritonitis is present.– Perforation is possible

Classification (2)

• Complications– Perforation– Peritonitis (local, spread, total)– Appendix mass– Appendix abscess– Pylephlebitis– Sepsis

Classification (3)Morbidity (complications after appendectomy) Early (up to 1w)

– Wound infection, hematoma, evisceration– Intraabdominal bleeding– Abdominal mass /abscess– Intestinal obstruction– peritonitis

Late (after 2w)– Wound fistula, mass– p/o hernia– Abdominal mass /abscess (right iliac fossa, pelvic, subphrenic)– Fecal fistula

Classification (4)

Medical complications• myocardial infarction

• pulmonary embolism

• Pneumonia

• Urinary tract infection

Problem:

despite diagnostic and therapeutic advancement in medicine, appendicitis remains a clinical emergency.

In fact, this illness is one of the more common causes of acute abdominal pain.

Left untreated, appendicitis has the potential for severe complications, including perforation or sepsis, and may even cause death

• The diagnosis of appendicitis is clinical and essentially is based on history and clinical examination findings. The classic form of appendicitis may be promptly diagnosed and treated.

• When appendicitis appears with atypical presentations, it remains a clinical challenge

typical presentations

The most common symptom of appendicitis is abdominal pain. Typically, symptoms begin as periumbilical or epigastric pain migrating to the right lower quadrant of the abdomen (Volkovich-Kocher’s sign)

Later, a worsening progressive pain along with vomiting, nausea, and anorexia are described by the patient. Usually, a fever is not present at this stage.

typical presentations

• Usually, patients are lying down, flexing their hips, and drawing their knees up to reduce movements and to avoid worsening the pain

typical presentations

• Tenderness on palpation in the RLQ over the McBurney point is the most important sign in these patients.

• Additional signs such as increasing pain with cough (ie, Dunphy sign),

• rebound tenderness related to peritoneal irritation elicited by deep palpation with quick release (Shchotkin- Blumberg sign),

• guarding (defence musculaire) may be present.

• palpation in the left iliac fossa reproduce pain in the right iliac fossa (Rovsing’s sign)

When the abdominal signs are vague:

• extension of the right thigh elicits pain (retroperitoneal or retrocecal appendicitis) Obraztsov sign

• Rectal or vaghinal examination (pelvic position)

DIFFERENTIAL DIAGNOSIS

OF ACUTE APPENDICITIS

• Mesenteric adenitis • Meckel's diverticulitis • Intussusception• Regional ileitis (Crohn's disease) • Acute gastroenteritis• Carcinoma of the caecum • Perforated peptic ulcer• Epiploic appendegitis

DIFFERENTIAL DIAGNOSIS OF ACUTE APPENDICITIS (cont.)

• Genitourinary– Pyelonephritis – Ureteric colic – Urinary tract infection – Right-sided testicular torsion

DIFFERENTIAL DIAGNOSIS OF ACUTE APPENDICITIS (cont.)

• Gynaecological disorders– Pelvic inflammatory disease – Ruptured ovarian follicle (Mittelschmerz) – Acute salpingitis – Ruptured ectopic pregnancy – Torsion of an ovarian cyst

WORKUPLab Studies: Laboratory tests are not specific for appendicitis but may be helpful to confirm

diagnosis in patients with an atypical presentation.• Complete blood cell count

A mild elevation of WBCs (ie, >12,000/mL) is a common finding in patients with acute appendicitis. In these patients, leukocytosis occurs. Otherwise, the WBC count has low specificity for appendicitis, and a number of bacterial and viral diseases may also lead to leukocytosis.– In infants and elderly patients, a WBC count is especially unreliable because these

patients may not mount a normal response to infection.– In pregnant women, the physiologic leukocytosis renders the CBC count useless for

the diagnosis of appendicitis.• Urinalysis

– Urinalysis may be useful in differentiating appendicitis from urinary tract conditions.– Mild pyuria may occur in patients with appendicitis because of the relationship of

the appendix with the right ureter. Severe pyuria is a more common finding in UTI– Proteinuria and hematuria suggest genitourinary diseases or hemocoagulative

disorders

Lab Studies (cont) :

• C-reactive protein (CRP) has been reported to be useful in the diagnosis of appendicitis. This protein is physiologically produced by the liver when bacterial infections occur and rapidly increases within the first 12 hours.– CRP lacks specificity and cannot be used to distinguish between sites of

infection.– CRP levels greater than 1 mg/dL commonly are reported in patients with

appendicitis. Very high levels of CRP in these patients indicate gangrenous evolution of the disease, especially if it is associated with leukocytosis and neutrophilia. However, CRP normalization occurs 12 hours after onset of symptoms.

• Liver and pancreatic function tests (eg, transaminases, bilirubin, alkaline phosphatase, serum lipase, amylase) may be helpful to determine the diagnosis in patients with an unclear presentation.

Lab Studies (cont) :

• For women of childbearing age, the level of urinary beta–human chorionic gonadotropic (beta-hCG) is useful in differentiating appendicitis from early ectopic pregnancy.

Lab Studies (cont) :

• According to a recent report, measurement of the urinary 5-5-hydroxyindoleacetic acid (U-5-HIAA) could be an early marker of appendicitis. The rationale of such measurement is related to the large amount of serotonin-secreting cells in the appendix.

• In the cited report, U-5-HIAA levels increase significantly in acute appendicitis, decreasing when the inflammation shifts to necrosis of the appendix. Therefore, such decrease could be an early warning sign of perforation of the appendix.

Imaging Studies

• Abdomen plain film: – Occasionally, a plain film of the abdomen may

demonstrate fecalith within the appendix, but this study is rarely indicated.

• Barium enema– Although barium enema is currently performed

only rarely, in the past this examination was used to diagnose appendiciti

Imaging Studies

• Ultrasound– A healthy appendix usually cannot be viewed with ultrasound

(US). When appendicitis occurs, the US typically demonstrates a noncompressible tubular structure of 7-9 mm in diameter.

• Vaginal ultrasound alone or in combination with transabdominal scan may be useful to determine the diagnosis in women of childbearing age.

• False-positive results may occur in patients with Crohn disease. False-negative results are frequent in patients with retrocecal appendix.

• The main limitation of US scan is that its reliability is completely user-dependent.

• a normal appendix. longitudinal (A) and transverse (B) sonogram, showing the appendix (arrowheads) with a diameter less than the 7 mm cut-off point, surrounded by normal noninflamed fat

• An inflamed appendix has a diameter larger than 6 mm, and is usually surrounded by hyperechoic inflamed fat at sonography

• Another supportive sign for appendicitis is hypervascularity of the appendix wall on color Doppler sonography

Imaging Studies

Computed tomography scan– CT scan with oral contrast medium or rectal Gastrografin enema

may help in diagnosis. Intravenous contrast is not usually necessary. It may help differentiate between appendicitis and other pelvic pathologies.

• The typical findings are a nonfilling appendix with distention and thickened walls of both the appendix and the cecum, enlarged mesenteric nodes, and periappendiceal inflammation or fluid.– Because of its cost, CT scans are generally reserved for patients

with uncertain diagnosis or severe obesity.– Recently, helical CT scan has demonstrated high sensitivity and

specificity in differentiating appendicitis from other conditions, and it may be cost efficient with regards to limiting the number of unnecessary operations.

• Normal CT of the appendix. CT scan demon-strates elongated appendix measuring 5 to 6 mm in diameter (arrow) with a small amount of air noted in the tip.

• Appendicitis. The appendix (solid arrows) is abnormally dilated and demonstrates a thickened enhancing wall and no filling with contrast.

• Perforated appendicitis. The appendix (solid arrows) is abnormally dilated with a thickened enhancing wall. Small pockets of extraluminal air (dashed arrows) indicate perforation

• Appendicitis with appendicolith. An enlarged appendix (solid arrows) is seen with an appendicolith (dashed arrows) at the base.

• At CT the inflamed appendix is surrounded by fat-stranding

A CT KUB was performed,. There are two appendicoliths in this retrocaecal appendix, a markedly distended lumen (appendix diameter 17mm, and inflammatory stranding in the surrounding fat.

Urolithiasis often causes flank pain, but an ureteral stone (arrowhead) may occasionally present with clinical signs simulating appendicitis, cholecystitis or diverticulitis.

• Mesenteric lymphadenitis is a common mimicker of appendicitis.

• It is defined as a benign self-limiting inflammation of right-sided mesenteric lymph nodes without an identifiable underlying inflammatory process, occurring more often in children than in adults..

• Pancreatitis

• CT depicts fat-stranding (arrowheads) surrounding the primary focus of the inflammation: the pancreas.

• Epiploic appendagitis has been reported in approximately 1% of patients clinically suspected of having appendicitis.

• Both US and CT will depict an inflamed fatty mass adjacent to the colon.

• Salphingitis is a common mimicker of both of appendicitis and diverticulitis.

• Transvaginal sonography depicts an inhomogeneous enlarged inflamed ovar

Diagnostic procedure

• Diagnostic laparoscopy may be useful in selected cases (eg, infants, elderly patients, female patients) to confirm the diagnosis. If findings are positive, such procedures should be followed by definitive surgical treatment at the time of laparoscopy.

Medical therapy:

• Appendectomy remains the only curative treatment for appendicitis.

• The only indication for non-operative treatment is an appendix mass– Antibiotics, IV fluids– Abscess - percutaneous drain

• colonoscopy/barium enema in a 6 weeks after initial presentation

• Interval appendectomy using laparoscopic approach

Surgical therapy:• Thousands of classic appendectomies (open procedure) have

been performed in the last 2 centuries. Mortality and morbidity have gradually decreased, especially in the last few decades because of antibiotics, early diagnosis, and improvements in anesthesiologic and surgical techniques.

• Since 1987, many surgeons have begun to treat appendicitis laparoscopically. This procedure has now been improved and standardized.– Certain contraindications exist for laparoscopic appendectomy. These

contraindications are extensive adhesions, radiation or immunosuppressive therapy, severe portal hypertension, and coagulopathies. Laparoscopic appendectomy is contraindicated in the first trimester of pregnancy

Acute appendicitis in young children

• Diagnosis is more difficult

• More rapid progression to peritonitis and rupture

Acute appendicitis in elderly

• Delay in diagnosis

• More rapid progression to perforation (older than age 80 years perforation rates of 49%,

mortality rates of21%)

• Comorbid diseases

– High index of suspicion should be maintained

Acute appendicitis during pregnancy

• Incidence is 1 in 2000 pregnancies• More frequent during first two trimesters• Rebound and guardian signs are less frequent• When diagnosis is in doubt, ultrasound may be

beneficial– The performance of any operation during pregnancy

carries risk of premature labor of 15 %

– The most significant factor associated with both fetal and maternal death is appendiceal perforation

Acute appendicitis in HIV infection

• Increased risk of appendeceal rupture (delay in clinical presentation)

• Possible cause of RLQ pain may be the opportunistis infections (CMV, Kaposhi sarcoma, TB, lymphoma, mucosal ischemia)

CONTROVERSIES

• If the surgeon finds a normal appendix, he or she is faced with a dilemma. At this point, other causes of the patient's condition should be ruled out, including ovarian pathology, Meckel diverticulum, sigmoid disease, and cholecystitis.

• Regardless of the findings, the authors believe that appendectomy should be performed. The patient will have a RLQ incision, and, in the future, physicians who examine the patient may assume that an appendectomy has been performed and they will not include appendicitis in the differential diagnosis.

CONTROVERSIES

• The nonoperative management of appendicitis with high doses of antibiotics is reported in some studies, but it seems to be effective in only 60% of patients. It may be useful (and should be considered) in rural areas or if a surgical facility is not in close proximity to the patient.