LWBK1006-43 LWW-Govindan-Review December 14, 2011 15:38
Chapter 43•Infections in the Cancer Patient 547are not active. Posaconazole has shown promising results as salvage
therapy.Answer 43.11. The answer is A.
Neutropenic patients with persistent fever are at risk for fungal pneu-
monia. CT imaging of the chest may disclose characteristic signs, such
as the nodules, masses, or the “halo sign.” This latter finding is highly
suggestive of invasive aspergillosis but may also be seen withP. aerugi-
nosaor other molds. The serum galactomannan assay is specific (although
not highly sensitive) for aspergillus species, because invasive zygomycosis
does not cause positive results. Prompt treatment with voriconazole or
amphotericin B is indicated.Answer 43.12. The answer is C.
The causative agents in esophagitis include candida, HSV, CMV, bacte-
ria, and aspergillus. Erosive esophagitis caused by radiation therapy or
chemotherapy-induced mucositis may also produce a similar clinical pic-
ture. CMV infections occur mainly in patients with prolonged immuno-
suppression, such as patients who have undergone hematopoietic stem
cell transplantation.Answer 43.13. The answer is B.
Typhlitis, or neutropenic enterocolitis, occurs in patients receiving
chemotherapy toxic to the bowel mucosa, most commonly during treat-
ment of acute leukemia. CT findings include bowel wall thickening,
mucosa edema, pericecal fluid, and a right lower quadrant inflammatory
mass. Treatment should consist of broad-spectrum antibiotics including
coverage against gram-negative and anaerobic organisms. CMV infection
is uncommon in patients with cancer without prior allogeneic stem cell
transplantation.Answer 43.14. The answer is B.
C. difficilecolitis is common in patients with cancer because of their fre-
quent exposure to broad spectrum antibiotics and recurrent hospitaliza-
tions that facilitate transmission. Treatment options forC. difficilecolitis
include oral metronidazole (or intravenous administration in those unable
to receive oral medications) and oral vancomycin. The latter option may
be considered in patients with severe diarrhea, significant comorbidities,
or persistent infections. Intravenous vancomycin is not effective because
it is not transported through the bowel wall. Fidaxomicin was recently
approved for the treatment ofC. difficilecolitis. The recommended dose
is 200 mg po bid for 10 days. Studies regarding the efficacy and safety of
probiotics have been inconclusive to date.Answer 43.15. The answer is D.
Anorectal infections are most commonly caused by organisms commonly
found in the gastrointestinal tract, such as Enterobacter species, Entero-
coccus,P. aeruginosa,or anaerobes, and are often polymicrobial. Digital
rectal examination should be avoided in patients with neutropenia. Broad-
spectrum antibiotics are required in anorectal infections, and anaerobic