Principles of surgery

PART II
Specific Considerations

CHAPTER 30
The Appendix

BASIC SCIENCE QUESTIONS

1. Which of the following is produced by the appendix?

A. T cells

B. B cells

C. IgG

D. IgA

Answer: D

For many years, the appendix was erroneously viewed as a vestigial organ with no known function. It is now well recognized that the appendix is an immunologic organ that actively participates in the secretion of immunoglobulins, particularly immunoglobulin IgA. (See Schwartz 9th ed., p 1073.)

2. Lymphoid tissue in the appendix

A. Is present at birth

B. Steadily increases in amount throughout life

C. Is maximally present during puberty

D. Disappears by the 5th decade of life

Answer: C

Lymphoid tissue first appears in the appendix approximately 2 weeks after birth. The amount of lymphoid tissue increases throughout puberty, remains steady for the next decade, and then begins a steady decrease with age. After the age of 60 years, virtually no lymphoid tissue remains within the appendix, and complete obliteration of the appendiceal lumen is common. (See Schwartz 9th ed., p 1074.)

3. The luminal capacity of a normal appendix is

A. 0.1 mL

B. 1 mL

C. 5 mL

D. 10 mL

Answer: A

The luminal capacity of the normal appendix is only 0.1 mL. Secretion of as little as 0.5 mL of fluid distal to an obstruction raises the intraluminal pressure to 60 cm H2O. (See Schwartz 9th ed., p 1075.)

CLINICAL QUESTIONS

1. Appendectomy may decrease the risk of developing which of the following diseases?

A. HIV

B. Burkitt’s lymphoma

C. Ulcerative colitis

D. Colon cancer

Answer: C

Although there is no clear role for the appendix in the development of human disease, recent studies demonstrate a potential correlation between appendectomy and the development of inflammatory bowel disease. There appears to be a negative age-related association between prior appendectomy and subsequent development of ulcerative colitis. In addition, comparative analysis clearly shows that prior appendectomy is associated with a more benign phenotype in ulcerative colitis and a delay in onset of disease. The association between Crohn’s disease and appendectomy is less clear. Although earlier studies suggested that appendectomy increases the risk of developing Crohn’s disease, more recent studies that carefully assessed the timing of appendectomy in relation to the onset of Crohn’s disease demonstrated a negative correlation. These data suggest that appendectomy may protect against the subsequent development of inflammatory bowel disease; however, the mechanism is unclear. (See Schwartz 9th ed., p 1073.)

2. Cultures should be taken at the time of surgery

A. For all patients with appendicitis

B. For all (but only) patients with perforated appendicitis

C. For immunocompromised patients with appendicitis

D. Never

Answer: C

The routine culture of intraperitoneal samples in patients with either perforated or nonperforated appendicitis is questionable. By the time culture results are available, the patient often has recovered from the illness. In addition, the number of organisms cultured and the ability of a specific laboratory to culture anaerobic organisms vary greatly. Peritoneal culture should be reserved for patients who are immunosuppressed, as a result of either illness or medication, and for patients who develop an abscess after the treatment of appendicitis. (See Schwartz 9th ed., p 1076.)

3. Which of the following is a positive Rovsing sign?

A. Pain with percussion of the right lower quadrant

B. Pain in the right lower quadrant with compression of the left lower quadrant

C. Cutaneous hyperesthesia in the T10-T12 distribution

D. Suprapubic pain on rectal examination

Answer: B

The Rovsing sign—pain in the right lower quadrant when palpatory pressure is exerted in the left lower quadrant—also indicates the site of peritoneal irritation.

The other three choices are important physical findings in appendicitis but are not the Rovsing sign. Pain with percussion in the right lower quadrant is rebound tenderness.

Cutaneous hyperesthesia in the area supplied by the spinal nerves on the right at T10, T11, and T12 frequently accompanies acute appendicitis. In patients with obvious appendicitis, this sign is superfluous, but in some early cases, it may be the first positive sign. Hyperesthesia is elicited either by needle prick or by gently picking up the skin between the forefinger and thumb.

With a retrocecal appendix, the anterior abdominal findings are less striking, and tenderness may be most marked in the flank. When the inflamed appendix hangs into the pelvis, abdominal findings may be entirely absent, and the diagnosis may be missed unless the rectum is examined. As the examining finger exerts pressure on the peritoneum of Douglas’ cul-de-sac, pain is felt in the suprapubic area as well as locally within the rectum. (See Schwartz 9th ed., p 1076.)

4. Which of the following is important to consider in the differential diagnosis of an HIV+ patient with right lower quadrant abdominal pain?

A. Herpes type 1 enteritis

B. Cytomegalovirus infection

C. Cecal volvulus

D. Small bowel diverticulitis

Answer: B

The differential diagnosis of right lower quadrant pain is expanded in HIV-infected patients compared with the general population. In addition to the conditions discussed elsewhere in this chapter, opportunistic infections should be considered as a possible cause of right lower quadrant pain. Such opportunistic infections include cytomegalovirus (CMV) infection, Kaposi’s sarcoma, tuberculosis, lymphoma, and other causes of infectious colitis. CMV infection may be seen anywhere in the GI tract. CMV infection causes a vasculitis of blood vessels in the submucosa of the gut, which leads to thrombosis. Mucosal ischemia develops, leading to ulceration, gangrene of the bowel wall, and perforation. Spontaneous peritonitis may be caused by opportunistic pathogens, including CMV,Mycobacterium avium-intracellulare complex, Mycobacterium tuberculosisCryptococcus neoformans, and Strongyloides. Kaposi’s sarcoma and non-Hodgkin’s lymphoma may present with pain and a right lower quadrant mass. Viral and bacterial colitis occur with a higher frequency in HIV-infected patients than in the general population. Colitis should always be considered in HIV-infected patients presenting with right lower quadrant pain. Neutropenic enterocolitis (typhlitis) should also be considered in the differential diagnosis of right lower quadrant pain in HIV-infected patients. Herpes type 1 does not cause enteritis. Cecal volvulus and small bowel diverticulitis are very rare, and no more likely to occur in an HIV patient than in someone without HIV infection. (See Schwartz 9th ed., p 1083.)

5. Incidental appendectomy is indicated in which of the following patients?

A. Otherwise healthy patients between the age of 16 and 30 years

B. Patients with Crohn’s disease with active disease in the appendix

C. Patients undergoing surgery who will be traveling to remote locations

D. Children between the age of 12 and 18 years with chronic recurring abdominal pain

Answer: A

Epidemiological data about appendicitis no longer supports incidental appendectomy in patients.

Although incidental appendectomy is generally neither clinically nor economically appropriate, there are some special patient groups in whom it should be performed during laparotomy or laparoscopy for other indications. These include children about to undergo chemotherapy, the disabled who cannot describe symptoms or react normally to abdominal pain, patients with Crohn’s disease in whom the cecum is free of macroscopic disease, and individuals who are about to travel to remote places where there is no access to medical or surgical care. (See Schwartz 9th ed., p 1088.)

6. A patient with a 1.5-cm carcinoid tumor of the mid appendix should undergo

A. Appendectomy only

B. Partial cecectomy and lymph node sampling to confirm negative margins

C. Resection of the cecum, terminal ileum, and adjacent mesentery (en bloc resection)

D. Right hemicolectomy

Answer: A

Because this is a tumor 2 cm in size in the mid appendix, an appendectomy is adequate treatment. (See Schwartz 9th ed., p 1088, and Fig. 30-1.)

Image

FIG. 30-1. Algorithm for the management of patients with appendiceal carcinoid.

7. At the time of laparoscopic surgery for presumed appendicitis, the patient is noted to have a mucous-filled, distended appendix measuring 3 cm in diameter. There is no acute inflammation or signs of perforation. The correct treatment for this patient is

A. Diagnostic laparoscopy only (no resection) with CT scan staging before proceeding with further surgery

B. Laparoscopic appendectomy with pathologic confirmation of a negative margin at the base of the appendix

C. Conversion to open appendectomy with pathologic confirmation of a negative margin at the base of the appendix

D. Right hemicolectomy

Answer: A

An intact mucocele presents no future risk for the patient; however, the opposite is true if the mucocele has ruptured and epithelial cells have escaped into the peritoneal cavity. As a result, when a mucocele is visualized at the time of laparoscopic examination, conversion to open laparotomy is recommended. Conversion from a laparoscopic approach to a laparotomy ensures that a benign process will not be converted to a malignant one through mucocele rupture. In addition, laparotomy allows for thorough abdominal exploration to rule out the presence of mucoid fluid accumulations. The presence of a mucocele of the appendix does not mandate performance of a right hemicolectomy. The principles of surgery include resection of the appendix, wide resection of the mesoappendix to include all the appendiceal lymph nodes, collection and cytologic examination of all intraperitoneal mucus, and careful inspection of the base of the appendix. Right hemicolectomy, or preferably cecectomy, is reserved for patients with a positive margin at the base of the appendix or positive periappendiceal lymph nodes. (See Schwartz 9th ed., p 1088.)

8. Which of the following is indicated in a patient with pseudomyxoma peritonei of appendiceal origin?

A. Right hemicolectomy

B. Hysterectomy with bilateral salgingo-oophorectomy

C. Abdominal XRT

D. Systemic chemotherapy

Answer: B

Pseudomyxoma is invariably caused by neoplastic mucussecreting cells within the peritoneum. These cells may be difficult to classify as malignant because they may be sparse, widely scattered, and have a low-grade cytologic appearance…. Thorough surgical debulking is the mainstay of treatment. All gross disease and the omentum should be removed. If not done previously, appendectomy is routinely performed. Hysterectomy with bilateral salpingo-oophorectomy is performed in women. Because 5-year survival of mucinous appendiceal neoplasms is only 30%, adjuvant intraperitoneal hyperthermic chemotherapy is advocated as a standard adjunct to radical cytoreductive surgery. Abdominal XRT and systemic chemotherapy are not used in the treatment of pseudomyoxa peritonei. Right hemicolectomy is not indicated as a routine procedure. (See Schwartz 9th ed., pp 1088-89.)

9. The treatment for lymphoma confined to the appendix is

A. Appendectomy alone

B. Appendectomy with systemic chemotherapy

C. Right hemicolectomy alone

D. Right hemicolectomy with systemic chemotherapy

Answer: A

The management of appendiceal lymphoma confined to the appendix is appendectomy. Right hemicolectomy is indicated if tumor extends beyond the appendix onto the cecum or mesentery. A postoperative staging workup is indicated before initiating adjuvant therapy. Adjuvant therapy is not indicated for lymphoma confined to the appendix. (See Schwartz 9th ed., p 1089.)