The correct Answers are: B,C
Crohn's disease of the colon is a patchy, segmental, chronic, transmural inflammatory process that penetrates the bowel wall to form fistulas but seldom causes rectal bleeding. In contrast, ulcerative colitis is a mucosal ulcerating process that extends continuously from the rectum to the more proximal colon and frequently bleeds. Both diseases can develop toxic megacolon, and both predispose the patient to increased risk of malignancy of the large intestine over the long term.
The correct answer is
ABD DISCUSSION:
Patients with colonic Crohn's disease who have minimal or mild rectal involvement can be treated by colectomy and ileorectostomy or by colectomy, closure of the rectal stump, and ileostomy. When severe rectal involvement is also present, proctocolectomy with permanent ileostomy is required. The Kock pouch (continent ileostomy) and the ileal pouch–anal canal operation are not performed for Crohn's disease because of the risk of recurrence of Crohn's disease in the ileal pouch in the postoperative period.
The correct answer is E.
The patient is suffering from hyperacute rejection due to the preformed anti-B ABO blood group antibody found in all type A positive individuals. Hyperacute rejection occurs within minutes to a few hours of the time of transplantation, and is due to the destruction of the transplanted tissue by preformed antibodies reacting with antigens found on the transplanted tissue that activatecomplement and destroy the target tissue. Preformed antibodies can also be due to presensitization to a previous graft, blood transfusion, or pregnancy.
Acute rejection due to antibody-mediated immunity (choice A) is incorrect because this patient suffered from hyperacute rejection (immediate) occurring within minutes to hours, rather than days.
Acute rejection due to cell-mediated immunity (choice B) will not occur until several days or a week following transplantation. Acute rejection is due to type II and type IV reactions. Chronic rejection, due to the presence of cell-mediated immunity to minor HLA antigens (choice C), occurs in allograft transplantation months to even years after the transplant. Chronic rejection is generally caused by both humoral and cell-mediated immunity. An accelerated acute rejection, occurring in 3-5 days, can be caused by tissue infiltration and destruction by presensitized T lymphocytes and macrophages (choice D) and/or antibody-dependent, cell-mediated cytotoxicity (ADCC). Note that this is not a hyperacute reaction.
The correct answer is D. The lesion is a malignant melanoma. Melanomas can develop either de novo or in an existing mole. Sunlight exposure is a significant risk factor and fair-skinned persons are at increased risk of developing melanoma. The most significant factor for long term prognosis is the depth of the lesion, since the superficial dermis lies about 1 mm under the skin surface, and penetration to this depth is associated with a much higher incidence of metastasis than is seen with a more superficial location.
The circumference of the lesion (choice A) is much less important than depth , since one form of melanoma (superficial spreading) can still have good prognosis despite large size, if it has not extended to the depth of the superficial dermal lymphatic bed.
The darkness (choice B) or degree of variation in color (choice C) do not have prognostic significance once melanoma is diagnosed.
Irregularity, or fuzziness at the border (choice E) of a mole-like lesion is a good clue to potential malignancy, but does not affect prognosis once a melanoma is diagnosed.
The correct answer is E.
The baby probably has congenital hypertrophic pyloric stenosis, which usually presents at several weeks of age. Partial surgical incision through the pylorus (pyloromyotomy) is usually curative.
Antacids (choice A) are beneficial in esophageal reflux and peptic ulcer disease.
Barium enema (choice B) can reverse intussusception in a child, but would not be therapeutic in this case.
Gastric resection (choice C) is not indicated, since the much less invasive procedure of pyloromyotomy is actually more effective.
Oral antibiotics (choice D) are not indicated, since this is not an infectious process.
