Bart Jan Kullberg

Recombinant Murine Granulocyte Colony-Stimulating Factor Protects against Acute Disseminated Candida albicans Infection in Nonneutropenic Mice

The effect of recombinant granulocyte colony-stimulating factor (rG-CSF) on acute disseminated Candida albicans infection in nonneutropenic mice was investigated. Mice treated with a single dose of rG-CSF showed a significantly reduced mortality (28% vs. 90%; P < .001). The outgrowth of C. albicans from the kidneys, spleens, and livers of rG-CSF-treated mice was significantly reduced (log cfu/g of kidney, 5.54 vs. 7.13; P < .001), as were circulating tumor necrosis factor-alpha and interleukin-1beta. After rG-CSF, the kidneys showed fewer infectious infiltrates, enhanced granulocyte influx, and almost complete absence of hyphal outgrowth. During peritoneal C. albicans infection, rG-CSF enhanced influx of granulocytes to the site of infection, and exudate granulocytes showed increased oxygen radical production. These results indicate that rG-CSF enhances host resistance to disseminated candidiasis in nonneutropenic mice through activation of granulocytes and their recruitment to the site of infection.

Defects in Host-Defense Mechanisms

Under normal conditions, large areas of the human body surfaces are colonized with microorganisms. The skin and the mucous membranes of the oropharynx, nasopharynx, intestinal tract, and parts of the genital tract each have their own microflora.1 These patterns of colonization are determined by microbial factors, exogenous factors, and host factors.

An open study on the safety and efficacy of fluconazole in the treatment of disseminated Candida infections in patients treated for hematological malignancy

Disseminated candidiasis is a serious infectious complication with a mortality as high as 50%. Standard therapy consists of parenteral amphotericin B which is associated with major side effects and prolonged hospitalization. The aim of the study was to assess the efficacy and safety of fluconazole in an open, noncomparative study. Fluconazole, as a single agent, was given intravenously for the first 3 days at a dose of 200 mg twice daily, followed by 200 mg twice daily orally until resolution of signs and symptoms or evident treatment failure. The study group comprised 24 consecutive patients of whom nine had acute and 15 chronic disseminated candidiasis. A clinical response was achieved in 67% of cases of acute disseminated candidiasis and in 86% of cases of chronic disseminated candidiasis. The median duration of therapy was 15 days and 6 months, respectively. Superinfections withAspergillus fumigatus developed in five patients who were persistently neutropenic. No drug-related toxicity was registered.

Patient Susceptibility to Candidiasis-A Potential for Adjunctive Immunotherapy

Candida spp. are colonizing fungi of human skin and mucosae of the gastrointestinal and genitourinary tract, present in 30–50% of healthy individuals in a population at any given moment. The host defense mechanisms prevent this commensal fungus from invading and causing disease. Loss of skin or mucosal barrier function, microbiome imbalances, or defects of immune defense mechanisms can lead to an increased susceptibility to severe mucocutaneous or invasive candidiasis. A comprehensive understanding of the immune defense against Candida is essential for developing adjunctive immunotherapy. The important role of underlying genetic susceptibility to Candida infections has become apparent over the years. In most patients, the cause of increased susceptibility to fungal infections is complex, based on a combination of immune regulation gene polymorphisms together with other non-genetic predisposing factors. Identification of patients with an underlying genetic predisposition could help determine which patients could benefit from prophylactic antifungal treatment or adjunctive immunotherapy. This review will provide an overview of patient susceptibility to mucocutaneous and invasive candidiasis and the potential for adjunctive immunotherapy.