Cancer patient bacterial infections

Lentinan and yeast glucan can enhance the resistance of a host to bacterial, fungal, viral or parasitic infections (Tab. 5) [28-30], which is a marked advantage for cancer patients, since infections caused by microorganisms often cause serious problems in tumor-bearing or AIDS patients whose immune responsiveness has deteriorated. 

There are a number of disorders, including cancer and shock, in which the concentrations of plasminogen activators increase. In addition, the antiplasmin activities contributed by tti-antitrypsin and a2-antiplas-min may be impaired in diseases such as cirrhosis. Since certain bacterial products, such as streptokinase, are capable of activating plasminogen, they may be responsible for the diffuse hemotthage sometimes observed in patients with disseminated bacterial infections. 

Neutropenia occurs when the percent of mature neutrophils plus the percent of bands (or immature neutrophils) times the WBC count is less than 500/mm3 (0.5 x 109/L). The risk of infection increases as the extent of neutropenia becomes severe and the duration increases. The assessment of infection is different in the neutropenic cancer patient. First, WBC counts may be profoundly low, so no left shift is available to evaluate. Second, there is no pus without WBCs. Some bacterial pneumonias may not be readily apparent by chest x-ray. Third, if patients are receiving steroids as part of the cancer treatment, fever curves may be blunted or absent. When a patient does have a fever and is neutropenic, prompt initiation of anti-infectives is necessary. 

Over the last fifty years, as chemotherapeutics for the treatment of cancer, bacterial infections, and to prevent transplant rejections have improved, there has been a concomitant increase in the number of patients suffering from fungal infections. In the past, most fungal infections were superficial, affecting only the skin, hair, or nails. However, as medical science has progressed in other disease areas, many more patients are immunocompromised, which has resulted in a greater incidence of systemic fungal infections. 

Historical reviews have revealed a number of clinical observations in which cancers were reported to regress in patients with bacterial infections. At least some of the anticancer effects of Streptococcal infections are mediated through... 

A major cause of morbidity and mortality in patients who receive cytotoxic treatment or radiotherapy for cancer is bacterial and fungal infections. Intensive chemotherapy is associated with fever and infection, and the development of neutropenia further increases this risk of infection. Consequently, maximum doses of some cytotoxic drugs are limited due to bone marrow toxicity. Higher doses of chemotherapy and radiation therapy have become possible due to a reduction in bone marrow damage with the availability of the CSFs for clinical use. 

AIDS is a life-threatening disorder because of the susceptibility of the immunocompromised patient to severe infections and certain forms of cancer.65 73 76 101.113 [n particular, patients with AIDS often suffer from severe viral infections (CMV, various herpesvirus infections), bacterial infections (Mycobacterium tuberculosis), fungal infections (Pneumocystis jiroveri), and infections caused by various other microbes and parasites. Patients with AIDS also develop relatively unusual neoplastic diseases, such as Kaposi sarcoma. 

Vancomycin is an especially useful antibiotic for treating infections in cancer patients on chemotherapy and renal patients on dialysis. Uniike mammalian celis, bacterial cells are surrounded by a fairly rigid celi wall, which is crucial to the bacterium s survivai. Vancomycin kills bacteria by interfering with their cell wall synthesis. 

Leukocytosis is a normal host defense to infection and is an important adjunct to antimicrobial therapy. Unfortunately, bacterial infection is a common complication of neutropenia from cancer chemotherapy. These patients are incapable of increasing their WBCs in response to infection. In fact, susceptibility to infection in these patients is highly dependent on their WBC status. Patients with neutrophil counts of less than 500 cells/mm are at high risk for the development of bacterial or fungal infections. The absence of leukocytosis also occurs in the elderly and in severe cases of sepsis. ... 

Most infections in cancer patients are caused by organisms colonizing body sites, such as the skin, oropharynx, and GI tract. About 80% of infecting bacterial pathogens are from the patient s endogenous flora. " The GI tract is the most common site from which infections in immunocompromised hosts originate. Periodontitis,... 

In 1893, William Coley, a surgeon at Memorial Hospital in New York City, deliberately injected a mixture of heat-treated bacterial cells into the tumours of his cancer patients. In all, he treated over 900 patients, and there were several dramatic remissions. He was inspired to do this by the observation that cancer patients sometimes experienced remarkable improvement in their condition following a serious bacterial infection. It was as if their already severely damaged bodies were somehow activated by the bacterial onslaught to mount a sustained attack on both the bacterial and cancer cells. Coley s toxins - usually a mixture of killed bacteria of the species Streptococcus... 

Significantly, Nauts attributes this astounding increase to the introduction, use, and overuse of antibiotics, which were, at least then, highly immunosuppressive. In confirmation, it turns out that bacterial infections are effective in the treatment of cancer 449 cases are cited that were cured of cancer when the patients suffered from bacterial infections. In other words, it can be said that bacterial infections activate the immune system. 

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