Sabiston Small bowel infections

Question 1

Typhoid Enteritis

Answer 1

-contaminated water supplies and inadequate waste disposal.
-primarily by Salmonella typhi
-penetrate the small bowel mucosa, > lymphatics
-Hyperplasia of the reticuloendothelial system, including lymph nodes, liver, and spleen
-Peyer patches > hyperplastic > ulcerate > hemorrhage or perforation.
-Diagnosis > organism from blood, bone marrow, and stool cultures
-Tx fluoroquinolones and third-generation cephalosporins.
-single perforation in the terminal ileum > simple closure
-Multiple perforations > resection with primary anastomosis

Question 2

Protozoa Enteritis in AIDS

Answer 2

-Cryptosporidium, Isospora, and Microsporidium
-most frequent class of pathogens causing diarrhea in patients with AIDS
-Diagnosis > acid-fast staining of the stool or duodenal secretions
-Immunochromatography Stool
-Tx > prophylactic cotrimoxazole and a highly active antiretroviral therapy

Question 3

Bacteria Enteritis in AIDS

Answer 3

• Salmonella, Shigella, and Campylobacter
  -diagnosis of Shigella or Salmonella > stool cultures.
  -Campylobacter > PCR techniques evaluating stool and serum
  -Bacteremia and serious infections > IV imipenem or ciprofloxacin if the organisms are multiply resistant

the pregnant patient may be safely treated with erythromycin

Question 4

Mycobacteria in Immunocopromised

Answer 4

-Mycobacterium tuberculosis or Mycobacterium avium complex (MAC)
-most frequent site of intestinal involvement of M. tuberculosis is the distal ileum and cecum
-bowel wall appears thickened, and an inflammatory mass often surrounds the ileocecal region
-Stricture and Fistula can Form
-caseating granulomas found most commonly in the lymph nodes
-Radiographic > thickened mucosa with distorted mucosal folds and ulcerations
-CT > thickening of the ileocecal valve and cecum.
-Tx for MAC > amikacin, ciprofloxacin, cycloserine, and ethionamide, Clarithromycin

Question 5

Viruses

Answer 5

-CMV is the most common viral cause of diarrhea in immunocompromised
-Enteric CMV > mucosal ischemic ulcerations
-Diagnosis > viral inclusion > intranuclear inclusion > owl’s eye appearance
-Tx > ganciclovir