Variability in cortisol assays creates an additional problem with setting criteria for a normal response to ACTH that apply to all centers. Two studies comparing cortisol results obtained with different assays showed a positive bias of radioimmunoassays and immunofluorometric enzyme assays of 10 to 50 percent compared with a reference value obtained using isotope dilution gas chromatography-mass spectrometry. As a result, in one study, depending on the combination of assay and criterion used, between 0 and 100 percent of healthy volunteers would be considered to have a normal response to ACTH. This illustrates the difficulty of interpreting cortisol responses that are close to the cutoff point. (3)
After an introductory section that summarizes the characteristics of infusion reactions and different approaches to classifying them, this review will focus on commonly used conventional cytotoxic drugs with a moderate to high incidence of infusion reactions, and the ways in which these reactions can be treated and/or prevented. Infusion reactions in patients receiving therapeutic monoclonal antibodies for cancer treatment are discussed separately, as are other cutaneous adverse effects associated with chemotherapy. (See "Infusion-related reactions to therapeutic monoclonal antibodies used for cancer therapy" and "Cutaneous side effects of conventional chemotherapy agents" .)
The degree and extent of bone loss is most closely related to cumulative corticosteroid dose. The most rapid rate of bone loss is during the first 3 to 6 months of therapy. All patients starting gluocorticoids at any dose with an anticipated duration of at least 3 months or longer should start calcium 1200-1500mg/day and vitamin D 800-1000 international units/day supplementation. These patients should also be counseled on smoking cessation and weight-bearing activities. Additionally, they should be assessed for fall risk, baseline height, and history of fragility fractures.