Genome-wide comparisons of gene expression in adult versus elderly burn patients.

PURPOSE: Mortality and morbidity rates of elderly burn patients remain high despite numerous advancements in modern burn care. While prior studies have offered first insights on the biochemical changes in elderly burn patients compared to adults, the underlying cellular responses remain largely unknown. In this study, we aim to characterize the transcriptome of elderly burn patients and compare it to adult burn patients to obtain insights into the underlying molecular responses post-burn and to elucidate the effect of advanced age on the acute burn response. MATERIALS AND METHODS: Microarray data obtained from the Glue Grant Trauma-Related Database was obtained from blood specimens for ten elderly patients (n = 10), each with a set of two sex and total body surface area (TBSA) matched adult controls (n = 20), during the acute phase post-burn. Adult and elderly demographics and clinical outcomes were contrasted using using the Chi-Square test, Fisher's Exact Test, or two-sample t-tests, as appropriate (p<0.05). Enrichment and heat maps were generated to compare gene expression in elderly versus adult burn patients. RESULTS: Supervised analysis identified multiple genes that were differentially expressed between the elderly and adult groups. Pathway analysis and heatmap generation suggest that elderly patients share a distinct hypo-inflammatory response in the acute post-burn phase with downregulation of a number of immune-related pathways, including those related to antigen processing, specifically via MHC class I, ubiquitination and proteasome degradation (p<0.001, FDR < .001). Cell signalling pathways, such as NF-κB, C-type lectin receptor, and T cell receptor signalling were also significantly downregulated in elderly burn patients, as well as those relating to antiviral immunity (p<0.001, FDR < .001). Many genes which were observed to be upregulated in elderly patients with high TBSA burn injuries were associated with destruction-related cellular pathways such as complement activation and immunoglobulin production (p<0.005, FDR <0.01). CONCLUSIONS: The altered inflammatory and immune responses at the transcriptome level in elderly patients after burn are indicative of a failure in elderly burn patients to initiate an appropriate inflammatory and stress response during the acute phase post-burn.

Utility of Specialized Imaging for Diagnosis of Chronic Wrist Pain.

Background Patients with chronic wrist pain often undergo imaging (such as magnetic resonance imaging [MRI], computed tomography [CT], or ultrasound [US]) prior to specialist assessment. Questions Is specialized wrist imaging performed prior to expert consultation necessary? Are there demographic differences between patients who do or do not receive preconsultation imaging? Patients and Methods A total of 115 patients referred to a tertiary hand center for chronic wrist pain and assessed by a hand surgeon were included. At initial consultation, surgeons were blinded to referral information and previous imaging results. The specialist performed a history, physical examination and reviewed X-rays. They established a clinical diagnosis and whether any additional investigations were needed. Prior MRI, CT, and/or US results were then reviewed and the specialists' clinical diagnosis was compared with the blinded referral diagnosis. Preconsultation imaging was categorized as having no value for diagnosis/management, some value, or high value. Results A total of 82 patients had imaging prior to specialist referral (69 MRIs, 11 CTs, and 16 ultrasounds). The majority of additional imaging (73%) was classified as unnecessary, including 77% of the MRIs and 100% of the ultrasounds. Of all the investigations performed, two CT scans were labeled highly valuable clinical aids. Older patients and those with radial-sided pain were less likely to receive preconsultation imaging. Six patients required further imaging after consultation. Conclusion Clinical assessment and X-rays are typically sufficient for a hand specialist to diagnose and manage chronic wrist pain and few patients require additional imaging. Level of Evidence This is a Level III study.