Histological changes in human skin 32 days after death and the potential forensic significance

Abstract

To observe the histological changes in human skin within 32 days after death to explore its potential significance in forensic practice. The intact full-thickness skin and subcutaneous tissue from the sternum of eight corpses were placed in an environment of 4–6 °C for 4 h, 6 h, 12 h, 18 h, 24 h, 36 h, 48 h, 60 h, 72 h, 84 h, 96 h, 6 d, 8 d, 10 d, 12 d, 16 d, 20 d, 24 d, 28 d, and 32 d. Then, the whole layer of the skin was stained with haematoxylin & eosin. The histological morphology of the epidermis, dermis and appendages (sweat glands, hair follicles, and sebaceous glands) was observed under an light microscope. The epithelial nucleus condensed at 24 h after death, and cell lysis was exhausted after 20 days. The post-mortem changes in the dermis occurred later than that of the epidermis (72 h), but after epidermal changes started, the change was more rapid. At 16 d, the layers had become homogenized. The epidermis and dermis had completely separated 24 d after death. The changes in the sweat glands appeared earlier (24 h) and disappeared later (32 days); the sebaceous glands and hair follicles began to undergo degenerative changes at 96 h after death, and at approximately 20 d, only their contour remained. There were individual and structural differences in the post-mortem histological changes in the skin. At 4–6 °C ambient temperature, some structures of the human skin still exist for a long time after death, and these structures can be used to identify the source of the tissue; post-mortem histological changes in the skin occur at specific times, which can be used to help infer the time of death. A comprehensive observation of changes in the skin composition/structure is required to comprehensively analyse possible death times.

Systematic review of pathologic markers in skin ischemia with and without reperfusion injury in microsurgical reconstruction: Biomarker alterations precede histological structure changes

“…Cao et al (2015) observed dense neutrophil infiltration 7 days after flap elevation (Figure 3). Inflammatory infiltration was not observed in postmortem studies (Ahmed Alaa El‐Din et al, 2021; Bardale et al, 2012; Castagnoli et al, 2003; Kovarik et al, 2005; Wei et al, 2020).…”

Estimation of Early Postmortem Interval from Long Noncoding RNA Gene Expression in the Incised Cutaneous Wound: An Experimental Study

“…Therefore, the current study was also conducted to evaluate the expressions of lncFAO, which were strongly associated with healing sequences, especially inflammation resolution and tissue repair [ 5 , 20 , 32 ]. We identified its specificity in wound dating estimation and stability during early PMIs (up to 24 h).…”

Recovery of proliferative fibroblast cells from refrigerated sheep skin after different postmortem time intervals and their characterization

“…3). It is thought that the individual cells in mammalian tissues die gradually over time suggesting gradual reduction in stem cell pool in postmortem tissues (Wei et al 2020). The time taken to have complete death of all cells in a tissue may depend upon several variables such as environmental temperature, chemical or radiation exposure, humidity, age, and health of an animal.…”

“…Collection of tissues from live animals present an ethical issue, however, accidentally dead animals (domestic or wild) and slaughterhouse is a potential alternate to harvest tissues. Death, however, brings successive cessation of metabolic activities and ultimately carcass decomposition compromising nuclear DNA integrity of the individual cells in postmortem tissues (7) and ultimately cell death. Cold storage of biological tissues has been shown to delay decomposition and cell death (8).…”