Infections

Infections can be transmitted during tattooing as the pigment penetrates the dermis and comes into contact with capillaries and lymph vessels.

The risk of acquiring a tattoo-related infection largely depends on the hygiene measures under which the tattoo is applied and the experience of the tattoo artist20,21. Pyogenic infections caused by staphylococci and streptococci are relatively common and can be acquired during the tattooing process, or afterwards if basic care measures are not taken. There is also the risk of systemic infections owing to bacteria that gain access to the body via tattoos, especially in view of the increased risk of endocarditis associated with tattoos. For this reason, patients with congenital heart disease should be advised against getting a tattoo, or at least be urged to wait until they have spoken to their cardiologist22.

Tattoos are also a known risk factor for viral infections such as hepatitis B23,24. Although scientific evidence and reports of anecdotal cases suggest that HIV and the hepatitis C virus can be transmitted through tattoos, epidemiologically this risk factor is not considered to be statistically relevant25. Regardless, it is important to underline that a person who has had a tattoo is not allowed to give blood for 6–12 months.

Potential genotoxic/cytotoxic effects

There have been some reports of malignant cutaneous tumours developing within tattoos, such as malignant melanoma, basal cell carcinoma, squamous cell carcinoma, and keratoacanthoma1, but what causes these tumours to appear in tattooed areas is still unknown. A variety of factors might be involved, including the inflammatory reaction triggered by the tattoo, the intradermal injection of potentially toxic or carcinogenic compounds, exposure to ultraviolet radiation, and above all, genetic factors.

Most colourants used for tattoos are pigments and dyes; one of the most popular colourants is made of ‘azo compounds’ and contains 3,3’-dichlorobenzidine (DCB). Although DCB has not been associated with cancer in humans, a study by Wang et al26 proved that it is photomutagenic in Salmonella bacteria TA102 and photocytotoxic and photogenotoxic in human Jurkat T-cells (lymphoblasts). However, in view of the large number of people who have tattoos and the few cases that have been reported, the association could be purely coincidental and for this reason in vitro experiments and prospective cohort studies should be conducted to determine the true association between tattoos and skin carcinogenesis27.

Koebner phenomenon

Figure 2 Coloured tattoo to the leg made 4 years ago

Figure 2 Coloured tattoo to the leg made 4 years ago

The Koebner phenomenon, also called the isomorphic response, refers to the appearance of skin lesions along a site of injury. Because of the trauma to the skin that tattoos cause, it can trigger the onset of different forms of dermatosis through the isomorphic Koebner phenomenon, described in patients with tattoos in association with sarcoidosis, pyoderma gangrenosum, and cutaneous lupus erythematosus 1,28,29.

Tattoo removal

Lasers based on the principle of selective photothermolysis are used to remove black and coloured tattoos with varying degress of success. The commonly used lasers for tattoo removal are the Q-switched 694 nm ruby laser and the Q-switched 755 nm alexandrite laser (used for removing black, blue, and green pigments), the 1064 nm Nd:YAG laser (used for removal of black and blue pigments), and the 532 nm Nd:YAG laser (used to remove red pigments). Each laser has its benefits, and determining the right laser is important in order to ensure a successful outcome, which is often unpredictable. The choice depends on the colour of the tattoo and the skin type of the patient and it is possible to have adverse effects following laser tattoo treatment, such as textural change, scarring, and pigmentary alterations.

For these reasons, a study by Cegolon et al30 underlines that people — especially adolescents and young people — should reflect seriously before having a tattoo and be informed about the risks connected to tattoo removal techniques by school counsellors and primary care physicians31,32.

Temporary tattoos

Temporary tattoos do not require intradermal pigment injection, as pigment is applied superficially to the corneal layer1. A temporary henna tattoo should last for approximately 2–6 weeks, until the outer layer of the skin exfoliates, depending on skin type, the area of application, sun exposure, and other factors such as bathing and activity level.

Henna is the dried and powdered leaf of the dwarf evergreen shrub Lawsonia inermis, a member of the family Lythraceae. To create the henna tattoo, a paste is made by adding water or oil to henna powder or to ground fresh henna leaves. Essential oils, dried powder of indigo plant leaves, mustard oil, lemon juice, nut shell, sugar, tannin concentrates obtained from brewing tea leaves, instant coffee powder, charcoal powder, and p-phenylenediamine (PPD) may be added to enhance the darkening effect33. In recent years, the temporary black henna tattoo (a combination of red henna and PPD) has become very fashionable, especially among adolescents and young adults in Western countries.

Adverse skin reactions caused by temporary tattoos

Figure 3 Coloured tattoos to the arm made at different times over the last 5 years

Figure 3 Coloured tattoos to the arm made at different times over the last 5 years

Natural henna tattoos are very safe and rarely cause adverse skin reactions. Indeed, there have only been rare reports of acute and delayed hypersensitivity reactions to this natural pigment. On the other hand, allergic contact dermatitis caused by black henna (which contains PPD derivatives) is very common and is the typical adverse skin reaction to this kind of temporary tattoo. The reactions usually manifest clinically as acute eczema (a dermal inflammatory reaction, non-contagious, and pruritic) and a single exposure is usually sufficient to trigger a reaction as henna tattoos tend to contain high concentrations of PPD. The eczema takes about 2–3 weeks to clear and the reaction can leave temporary post-inflammatory hypopigmentation over the original form of the tattoo9,33,34.

Body piercing

Body piercing is the practice of attaching adornments (jewellery) to the body through the skin, mucosa, or tissue. This form of body art has been used by many civilisations throughout history. There are many different kinds of body piercings and they can be classified as the following5,35,36

  • Standard piercings are a hole through which small bars or rings can be inserted and perhaps decorated with a small metal or plastic bead
  • Dermal anchoring (or punching) involves making a single hole in the skin and inserting an anchor under the skin into which an adornment is then screwed
  • Surface bar piercing involves making an entry and exit hole on the same plane and inserting a metal bar through the holes and attaching beads to either end
  • Pocketing technique is similar to surface bar piercing, but the bead is placed in the centre of the bar rather than at the ends.

Adverse skin reactions caused by piercings

The risk of acute complications following a body piercing depends on the experience of the piercer, on the hygiene conditions used, on piercing aftercare, and also varies greatly in accordance with the part of the body pierced. According to available data, the likelihood of developing an adverse skin reaction is greater with piercings than with tattoos1,5,36–39.

Infections

Local infections are common, occurring in 10–20% of cases, and the most common bacteria involved are Staphylococcus aureus, group A streptococci, and the Pseudomona species, while less common are the infections connected to coagulase negative staphylococci, Lactobacillus, Mycobacterium tuberculosis, and atypical mycobacteria. In most cases, these infections are self-limiting and they improve quickly with topical antibiotics, but occasionally they may result in very serious conditions such as chondritis or cellulitis, which are treated by removing the piercing and administering systemic antibiotics1,37.

With regard to systemic infections, body piercings are a risk factor for endocarditis, which is increased in patients with congenital or acquired heart disease so they should follow the same recommendations mentioned for tattoos37,40–43.

There have also been reports of hepatitis B, C, and D, as well as HIV infections after body piercing, although not all studies have succeeded in demonstrating a causal link. Certain parts of the body, such as the nipples, the navel, or the genital area heal slowly (up to 6 months) and are associated with a considerably increased risk of secondary infection9.