Prevention of infection among patients with cancer

Multidrug-Resistant Gram-Negative Bacilli: Infection Control Implications

Antimicrobial resistance is a common iatrogenic complication of both modern life and medical care. Certain multidrug resistant and extensively drug resistant Gram-negative organisms pose the biggest challenges to health care today, predominantly owing to a lack of therapeutic options. Containing the spread of these organisms is challenging, and in reality, the application of multiple control measures during an evolving outbreak makes it difficult to measure the relative impact of each measure. This article reviews the usefulness of various infection control measures in containing the spread of multidrug-resistant Gram-negative bacilli.

Host impairments in patients with neoplastic diseases

Healthy individuals possess an immune system comprising physical barriers, innate and acquired immunity as well as the indigenous microflora that populate the body surfaces. The immune system maintains constant vigilance over the body at the cellular level as well as at the interface between the host integument and the resident microflora. However, neoplastic diseases and their treatment often lead to impaired immunity resulting in an increased risk of infections due to viruses, bacteria, fungi, and protozoa. This chapter explores the various aspects of host impairment focusing on the components of immunity and the interplay between them to explain why it is that these patients succumb to infections per se. In so doing, we hope that the reader will be better equipped to understand the risks patients face so as to anticipate potential infectious complications and implement appropriate measures to help attain successful remission of the neoplastic diseases and maintain the best quality of life for the patient.

Importance of antifungal drug-resistance: clinical significance and need for novel therapy

The incidence of fungal infections has increased dramatically over the past few decades due to the increase in the members of the population susceptible to such infections. This population includes individuals undergoing chemotherapy for cancer, those enduring long-term treatment with antibacterial agents, those receiving immunosuppressive drugs following transplantations, or those immunosuppressed due to diseases, such as AIDS, or malignancies. Newer antifungal agents, namely the triazoles, have aided in both the treatment of fungal infections and in the prevention of disease in susceptible individuals. However, resistance to the azoles, as well as to the polyenes, has resulted in clinical failures. Only a few potential antifungal targets have been exploited to date and there is a critical need for the discovery and development of novel antifungal agents that will result in improved therapy in this ever-expanding patient population. An increased intensity in the study of fungal pathogens at the molecular level holds the key to such advances.

Interactions between antibiotics and antineoplastic drugs on antibacterial activity in vitro

The effects of various combinations of antibacterial (ampicillin, cephadroxil, doxycycline, imipenem, trimethoprimsulfadiazine) and antineoplastic (cisplatin, epirubicin, mitoxantrone) drugs were evaluated in vitro with regard to antibacterial activity on five clinical isolates from cancer patients of respectively Escherichia coli, Staphylococcus aureus and Streptococcus faecalis. With one exception no significant effects on the bacterial growth were observed in the presence of the antitumor drug alone. In contrast, all five strains of Strept. faecalis grew better when mitoxantrone was included in a concentration of 0.1 mg/l. A synergistic action between imipenem and mitoxantrone was seen for single strains of Staph. aureus and E. coli. Furthermore, a dose-effect related inhibition by cisplatin on the growth of Strept. faecalis in the presence of sub MIC levels of trimethoprimsulfadiazine was observed. The study indicates that interaction between antibacterial and antineoplastic drugs is an erratic phenomenon, which has to be dealt with separately for each combination of drugs as well as for each bacterial strain.