Role of toll-like receptor 4 mutations in gram-negative septic shock

Current trends of clinical and genetic characteristics influencing the resource use and the nurse-patient balance in an intensive care setting

PURPOSE

To determine the impact of resource use on the nurse/patient ratio in a pediatric intensive care unit (PICU). To examine the longitudinal influence of chronic or genetically influenced diseases on this interrelation.

MATERIALS AND METHODS

Overall, 1586 patients admitted to the PICU through various modes of admission during a 5-year period were prospectively studied.

RESULTS

The mean daily number of bed use increased from 5 to 8.1, leading to a significant skew from the ideal nurse/patient ratio of 1:1, to an overloaded one of 1:3-5. An increasing longitudinal trend of patients with metabolic diseases (P < .0001) or with genetic influence (62.8% in 1997, 70.7% in 2001) was noted. More patients with a genetic influence died than those without (13.8% vs 8.5%, P < .001), and more patients supported by mechanical ventilation suffered from a genetically influenced disease (64% vs 36%, P < .03). The mortality rate showed a trend for longitudinal reduction from 12.6% to 12%.

CONCLUSIONS

The increasing trend of occupation of PICU bed and ventilator days by patients with chronic diseases may be related to the increasing trend of hospitalization of patients with recognized genetic influence. Although this new trend does not influence mortality, it significantly increases resource use and has a large impact on the staffing needs.

Single nucleotide polymorphisms of Toll-like receptors and susceptibility to infectious disease

Toll-like receptors (TLRs) play an important part in the innate immune recognition of invading microorganisms, initiating sufficient immune responses. Growing amounts of data suggest that the ability of certain individuals to respond properly to TLR ligands may be impaired by single nucleotide polymorphisms (SNPs) within TLR genes, resulting in an altered susceptibility to, or course of, infectious or inflammatory disease. Most studies have focused on two cosegregating SNPs-Asp299gly and Thr399Ile-within the gene encoding TLR4, the receptor for bacterial lipopolysaccharide. These SNPs are present in approximately 10% of white individuals, and have been found to be positively correlated with several infectious diseases. However, these SNPs seem to protect from atherosclerosis and related diseases, which is reviewed in this article also. Meanwhile, SNPs of genes encoding other TLRs-eg, TLR2, which recognises a wide variety of microbial ligands-have been reported, and preliminary studies indicate an impact on susceptibility to infectious and inflammatory diseases as well. This review summarises and discusses the results obtained, and draws conclusions from these data.