Devita, Hellman, and Rosenberg's Cancer

LWBK1006-43 LWW-Govindan-Review December 14, 2011 15:38

548 DeVita, Hellman, and Rosenberg’s CANCER: Principles and Practice of Oncology Review

coverage is also indicated in the presence of fistula formation, induration,

or cellulitis. Local comfort measures may also be used, but antibiotic treat-

ment should be initiated without delay. Pelvic CT to rule out perirectal

abscess requiring surgical management should also be considered.

Answer 43.16. The answer is C.

Patients with cancer who are suspected to have meningitis an appropri-

ate initial antibiotic regimen should cover (S. pneumoniae, N. meningi-

tidis, H. influenzae) along with Listeria and penicillin-resistantS. pneu-

moniae.The vancomycin, ceftriaxone, and ampicillin regimen would be

an appropriate empiric antibiotic regimen. If the patient is allergic to peni-

cillin, then TMP/SMX could be substituted for ceftriaxone. Patients who

had undergone stem cell transplant within the last 2 months should be

treated for possible pseudomonas infection, therefore substituting ceftri-

axone with cefepime or meropenem would be appropriate. In this patient,

the presence of mental status changes raises the possibility of encephalitis

and intravenous acyclovir for the treatment of HSV encephalitis should

be included.

Answer 43.17. The answer is C.

Brain abscesses may present with symptoms including headache, neuro-

logic deficits, or seizures, and appear as ring-enhancing lesions on MRI. In

immunocompetent patients, bacterial brain abscess is frequently caused

by dental flora. Third-generation cephalosporins, such as ceftriaxone and

metronidazole, are recommended for empiric therapy, particularly in a

patient with a suspected oral source. Voriconazole may be added to broad-

spectrum antibacterial coverage in immunocompromised patients, who

are more likely to have a fungal cause.

Answer 43.18. The answer is A.

Liver-directed therapies, such as chemoembolization and radiofrequency

ablation, are effective palliative measures in selected patients with hep-

atic tumors. Resultant tumor necrosis may serve as a nidus for infection,

with an incidence of approximately 1% after these procedures. Prior bil-

iary enteric anastomosis is the primary risk factor for liver abscess after

chemoembolization, with an incidence of approximately 5% in these

patients.

Answer 43.19. The answer is D.

Enterococcus species are common pathogens in bacteremia. Colonization

with VRE is frequently detected in patients with cancer with repeated

hospitalizations. VRE bacteremia typically occurs in severely debilitated

patients and is associated with high mortality. First-line agents include

linezolid and daptomycin. Quinupristin-dalfopristin is effective inEntero-

coccus faeciuminfections, but notEnterococcus faecalis,and has moder-

ate efficacy comparable to linezolid. Unfortunately, refractory bacteremia

is not rare in this disease.