by: Harina Vin
Forensic science, as defined by Wikipedia, is “the application of a broad spectrum of sciences to answer questions of interest to a legal system.” One such science, currently undeveloped for use in forensics, is dermatology and dermatopathology. Examination of the skin is a critical part of the forensic examination, as the skin has the potential to reveal signs of internal disease or external trauma, an approximate time of death or injury, or clues to the identity of an individual.
Detection of Drug and Chemical Use
The simplest way to detect drug and chemical use of an individual in forensic cases is to analyze hair and nail samples. This method is particularly useful because it is easily and non-invasively collected.3 Biological substances accumulate in hair and nail, where they can be measured even in small sample sizes. The hair and nails may also give a history of drug intake and abuse, as well as toxin exposure. The nail on the large toe reflect body exposure to toxins up to 12 months previous.3 In the same way, long scalp hair may provide retrospective information of the previous 5 to 7 years. In fact, the basic chemical composition of the hair shaft and nail plate is not influenced by changes in the blood chemistry or by exposure to chemicals which occurred after hair and nail formation.9, 10
Transverse leukonychia, also known as Mee’s lines, are nail abnormalites caused by toxins like arsenic and thallium.13, 16 Fingernail clippings of victims have been utilized in looking for the DNA of aggressors in cases where the victims struggled to defend themselves.8 The identification, however, may be difficult due to the fact that the aggressor’s DNA is often too low in quantity to be detected. Certain hair loss patters are indicative of some poisoning which may lead to the diagnosis.5
In a case study, a 16-year-old girl was admitted to a hospital for weakness and weight, and was found to have white, transverse, and nonpalpable lines on each of her nails. Dermatology was consulted regarding the patient’s abnormal nails, consistent with Mee’s lines. The patient’s hair and nails were analyzed and arsenic was found, initiating a criminal investigation. The investigation uncovered the following:
“Upon taking further history, her father had died recently. His body was exhumed and arsenic was found. It was then discovered that the previous husband of the child’s mother had died in middle age. His body was exhumed and arsenic was again found. About that time, the mother disappeared. She was found several years later and charged and convicted of murder and attempted murder.”3 In this case, dermatologic symptoms allowed the discovery of a legal incident using hair and nails.
Detection of Abuse
In living patients, certain chronic and recurring dermatologic symptoms can occur in patients following psychologic trauma events. Examples are cutaneous sensory flashbacks, autonomic hyperarousal (with symptoms such as profuse sweating or flare-up of an underlying stress-reactive dermatosis), conversion symptoms (such as numbness, pain, or other medically unexplained cutaneous symptoms), and cutaneous self-injury (manifesting in many forms, including trichotillomania, dermatitis artefacta, and neurotic excoriations— tension-reducing behaviors in patients who have posttraumatic stress disorder).4 These dermatologic symptoms can be indicative of psychological abuse and pursued by forensic scientist.urn victims also exhibit certain skin characteristics. In electrical lesions, cell cytoplasm appears homogeneous often with a peculiar white color in hematoxylin-eosin stained sections, and overall morphology of the cells are affected, likely because of pH shifts in the cells.15
Interestingly, forensic dermatology can also be used to rule out abuse. A case study was conducted of an 82-year-old man in a nursing home receiving treatment for colon cancer. One night, he unexpectedly dies. His right cheek is described as “red with blisters” and his family is concerned that he had experienced a burn to his face due to neglect or abuse from the nursing home staff. An autopsy is performed which confirms a diagnosis of metastatic adenocarcinoma of the colon. Skin biopsies are also performed, and cells of the epidermis stain positively for antivaricella zoster antibody. Afterward, the viral tissue culture grows varicella zoster virus. The findings established “herpes zoster as the cause of the man’s right cheek erythematous-based blisters and excluded the possibility of a burn, neglect, or abuse by the nursing home staff.”2
Time of Death
Attempts to estimate age of skin bruises is of considerable importance in forensic pathology. One way age is estimated is using time-dependent changes of color. For example, a bruise older than 18 hours is predicted to appear yellow in light-microscope histology. 6 Apoptosis activity found in the post-mortem skin is most probably reliable way of determining age of an injury.12 In general, the apoptotic process is associated with condensation of cytoplasm followed by phagocytosis and digestion by surrounding cells, the steady state mass of a tissue being related to the balance between cell formation (mitosis) and cell destruction (via apoptosis).7 Thus, the relationship betweenapoptosis and physical injury in skin, can aid forensic dermatologist in identifying time of death. mass of a tissue being related to the balance between cell formation (mitosis) and cell destruction (via apoptosis).7 Thus, the relationship betweenapoptosis and physical injury in skin, can aid forensic dermatologist in identifying time of death.
Some obvious method for identification of unknown human bodies are visual identification, fingerprints, and DNA fingerprinting.17 One more important and less spoken forensic tool to establish identity in an unknown deceased is occupational skin lesions, that is, lesions acquired in the course of a person’s daily profession. Different occupations produce characteristic effect on different parts of body due to use of tools or machines or exposure to different chemicals in the working environment. Examples of profession-specific dermatologic indicators include “ rough hands seen in manual labourer involved in construction work, excavated chest in a cobbler, callosities of finger tips in a stenographer, callosities of palm at the base of fingers in butchers, burn scars over the back of both hands seen in blacksmiths, involuntary permanent tattooing of micro particles of coal found on the hands of the labourers involved in mining industry.”11
A rare case was reported, where the identity of an unknown elderly male who committed suicide by hanging was established based on the symmetrical distribution and pattern of skin lesions acquired during the course of his occupation. As a coconut tree climber, he gripped the coconut tree with both hands and feet, and then pushed up the body to climb higher. This resulted in intermittent pressure over the forearm skin, palms, and soles in response to friction, causing deposition of thickened, vertically oriented collagen bundles in papillary dermis, resulting in lichenification.1 The family of the individual later confirmed his identity.
Within the next decade, it is likely that the implementation of currently available and new techniques for the diagnosis and relevance of skin and mucosal conditions will continue to provide significant scientific advances in this promising area of forensics.2 These fields are awaiting further definition, categorization, and investigation.
1. Adams R.M. Occupational skin disease. In: I.M. Freedberg, A.Z. Eisen, K. Wolff, K.F. Austen, L.A. Goldsmith, S.I. Katz and al. et, Editors, Fitzpatrick’s Dermatology in General Medicine, McGraw-Hill, New York (1999), pp. 1609–1620.
2. Cohen P.R. Forensic Examiner [Online] Fall 2009.
3. Daniel C.R.; Piraccini B.M.; Tosti A. Journal of the American Academy of Dermatology. [Online] 2004, 50.2, 258-261.
4. Gupta M.A.; Lanius R.A.; Van der Kolk B.A. Dermatologic Clinics. [Online] 2005, 23.4, 649-656.
5. Hubler W.R. South Med J. [Online] 1966, 59, 436–442.
6. Langlois N.E. and Gresham G.A. Forensic Sci. Int. [Online] 1991, 50, 227–238.
7. Olson P.L. and Everell M.A. J. Cutaneous Path. [Online] 1975, 2, 53–57.
8. Oz C. and Zamir A. J Forensic Sci. [Online] 2000, 45, 158–160. Palmeri A; Pichini S; Pacifici R; Zuccaro P; Lopez A. Clin Pharmacokinet. [Online] 2000, 38, 95-110.
9. Pichini S; Altieri I; Zuccaro P; Pacifici R. Clin Pharmacokinet. [Online] 1996, 30, 222-228.
10. Polson C.J.Identification. In: C.J. Polson and Gee DJ, Editors, The Essentials of Forensic Medicine, Pergamon press, Oxford (1973), pp. 85–87.
11. Sawaguchi T; Jasani B; Kobayashi M; Knight B. Forensic Science International. [Online] 2000, 108.3, 187-203.
12. Seavolt M.B.; R.A. Sano; K. Levin; C. Camisa, Int J Dermatol. [Online] 2002, 41, 399–401.
13. Shetty B.S.; Rao, J; Samer K.S.; Salian P.R., Shetty M. Forensic Science International. [Online] 2009, 183.1, 17-20.
14. Thomsen H.K.; Nielsen D.O.; Aalund O.; Nielsen K.G.; Karlsmark T. Genefke I.K. Forensic Science International [Online] 1981, 17.2, 145-152.
15. Tromme I.; Van Neste D.; Dobbelaere F.; Bouffioux B.; Courtin C.; Dugernier T. Br J Dermatol [Online] 1998, 138, 321–325.
16. Weedn V.W. Clin. Lab. Med. [Online] 1998, 18, 115–137.