Non-nephrotoxic empiric antimicrobial therapy in febrile neutropenic cancer patients

Ciprofloxacin plus piperacillin is an equally effective regimen for empiric therapy in febrile neutropenic patients compared with standard therapy

The purpose of this study was to test the comparative efficacy and toxicity of empiric gentamicin and ciprofloxacin, in combination with piperacillin, in febrile patients with treatment-induced neutropenia. Fifty patients were prospectively randomized to receive piperacillin plus gentamicin (PG), and 46 were randomized to receive piperacillin plus ciprofloxacin (PC). The groups were similar in age, sex, diagnosis, duration of neutropenia, and incidence of positive cultures. The two antibiotic regimens were associated with comparable rates of defervescence in the patients with gram-positive bacteremia. In the patients with gram-negative bacteremia and those with negative cultures, however, defervescence was more prompt in the PC group. In particular, 27% of the culture-negative patients on PC, compared to only 5% of those on PG, defervesced within 72 hr (P = 0.015). Because of the more prompt defervescence in the PC group, amphotericin B was used less frequently; 78% of the patients on PG compared with only 56% of those on PC were started on amphotericin B (P = 0.025). PC is an effective alternative to the more traditional PG for treatment of febrile neutropenic hosts who have not been given prophylactic quinolones. More important, PC appears to hasten defervescence compared with PG, especially in culture-negative patients and those with gram-negative bacteremia, and may decrease the necessity of additional antimicrobial agents such as amphotericin B.

The use of quinolones as therapy in granulocytopenic cancer patients. Comparison with other antimicrobials

Quinolones are valuable antimicrobial agents for prevention and therapy of febrile neutropenia. However, as with other groups of antibacterials, there are limitations to the use of quinolones in immunocompromised hosts: they should not be used in those neutropenic patients receiving ciprofloxacin or ofloxacin for prophylaxis, because of the risk of infection with resistant Gram-negative, or less susceptible Gram-positive, organisms. There are also insufficient data to support monotherapy of febrile neutropenia with quinolones, although some studies using higher ciprofloxacin dosages have reported encouraging results. More data on this issue, including use in paediatric cancer patients, are required. Quinolones are indicated for empirical therapy in combination with agents active against Gram-positive organisms, such as broad spectrum penicillins with or without beta-lactamase inhibitors, or in combination with vancomycin or teicoplanin. Some studies have shown that a combination of cefotaxime or ceftriaxone may provide better coverage against streptococci, but there are insufficient data on the combination of quinolones with third generation cephalosporins. A specific group of patients with low risk mild to moderate neutropenia with solid tumours may benefit from oral therapy with quinolones in combination with either an aminopenicillin with a beta-lactamase inhibitor or clindamycin. After 10 years of quinolone use in febrile neutropenia, these agents can still be regarded as valuable drugs of choice; however, the incidence of resistance among staphylococci and Pseudomonas spp., especially in centres using quinolones as prophylaxis, is increasing.

Use of the quinolones for the prophylaxis and therapy of infections in immunocompromised hosts

The prevention and treatment of infections are major issues of supportive care in patients with haematological malignancies. Because of their broad antimicrobial activity, the use of fluoroquinolones for prophylaxis in neutropenic patients has been extensively studied. In comparison with placebo, norfloxacin reduces the incidence of Gram-negative infections, whereas Gram-positive bacterial and fungal infections remain unaffected. Ofloxacin and enoxacin also bacterial and fungal infections remain unaffected. Ofloxacin and enoxacin also produce a reduction in fever and documented infections. In randomized studies comparing ciprofloxacin with cotrimoxazole (trimethoprim/sulfamethoxazole) plus colistin (each in combination with nonabsorbable antifungal agents), conflicting results were obtained. The incidence of documented Gram-negative bacterial infections was markedly reduced by ciprofloxacin prophylaxis; however, the number of Gram-positive infections may increase dramatically. Combining ciprofloxacin with a macrolide antibiotic in an attempt to prevent streptococcal infections can result in breakthrough bacteraemias due to resistant Gram-positive pathogens. Empirical antimicrobial therapy after quinolone prophylaxis should also be directed against microorganisms susceptible to quinolones, since sustained eradication by oral administration cannot be assumed with certainty. Clinical trials comparing intravenous quinolones in combination with aminoglycosides with widely used standard regimens for the treatment of infections in cancer patients indicate equivalent efficacy; however, in studies of ciprofloxacin alone, response rates were significantly lower compared with standard combinations. Therefore, quinolone monotherapy as empirical treatment in febrile neutropenic patients cannot be recommended.