Skin infections and soft-tissue conditions are known to be common in older adults (Laube and Farrell, 2002), and the focus of this article is to look at the available research in order to obtain an overview of the guidance when considering if a patient has a skin infection.
Prevalence
Hahnel et al (2017) investigated the prevalence of skin diseases in older nursing home residents while also exploring the possible associations of these with demographic and medical characteristics. Their research was a descriptive multicentre prevalence study and was conducted in a random sample of 10 institutional long-term care homes in Berlin, Germany. A total of 223 residents were included as participants. Hahnel et al (2017) found that 60 dermatological diseases were diagnosed among their sample. The most frequently diagnosed skin disease was xerosis cutis (99.1%), followed by tinea unguium (62.3%) and seborrheic keratosis (56.5%). The study identified only few bivariate associations linking skin diseases and demographic and medical characteristics. Hahnel et al (2017) concluded that their results indicated that almost every individual living in residential care has at least one dermatological diagnosis. Dermatological findings from their research ranged from the highly prevalent xerosis and cutaneous infection to skin cancer. Hahnel et al (2017) explained that not all conditions required immediate dermatological treatment and could be managed by targeted skin care interventions, such as appropriate antibacterial dressings, good hygiene and teaching the patient about skin care and how to avoid infections or to identify possibilities of conditions developing. The researchers also stated that caregivers would need knowledge and diagnostic skills to ensure that the appropriate clinical decisions are made in these situations.
However, the authors also acknowledged that it would be unlikely that specialised dermatological care could be delivered widely in the growing long-term care sector (Hahnel et al 2017), given the large number of patients needing long-term care in this sector, and skin conditions being so common that it would be difficult to have the correct number of specialists to match this demand. Financial factors influence the care home sector, and it is difficult to fund dermatologists widely for this large cohort of people.
Therefore, it is important for nurses, carers and other health professionals to be able to distinguish what needs to be done if a skin infection is suspected in a patient.
Laube and Farrell (2002) noted that skin and soft tissue infections are common among older people, and provided appropriate guidance that is still relevant 18 years on. The authors covered the diagnosis and treatment of common bacterial skin infections (Laube and Farrell, 2002).
A range of special conditions and circumstances would need to be considered in the diagnosis and treatment of such conditions. Most importantly, community nurses should try to identify the causative organism, exclude other cutaneous disorders and identify precipitating factors (Laube and Farrell, 2002). Redness of the skin or inflammation, if the area is hot to touch or very itchy and oozing discharge, or a hard-to-heal wound are all signs of potential infection. This may be true for a redness that has gradually expanded away from the wound site or tracked along a vein, for example. Skin infections are especially important to identify as, if left long enough and ignored, they can easily progress to full-blown sepsis. Among vulnerable individuals, the environment of skin infections is optimal to develop such a serious condition, and this is why appropriate informed action is essential to prevent something as serious and fatal as sepsis. Therefore, alongside noting the symptoms and communicating with the district nurse and GP about any suspicions, best practice would be to take a wound swab. Blood cultures should be taken if there are indications that the infection has entered the bloodstream, for example, if the patient has a fever. A discussion with the tissue viability nurse associated with the team would be important in this scenario.
Treatment modalities to start the patient on following a discussion with the prescribing doctor or tissue viability nurse prescriber would include antiseptics, topical and systemic antibacterials, dressings and biotherapy. Skin infections often present with erythema, blisters, pustules and ulcerations, and nurses should look out for these conditions, especially in body folds.
Common skin infections
Laube and Farrell (2002) reported that cellulitis and infected ulcers were the most commonly encountered cutaneous infections in older adults.
Staphylococcus aureus and beta-haemolytic streptococci are the most common causative organisms of cutaneous infections, and accurate and rapid diagnosis and treatment are crucial to prevent significant morbidity from skin infections (Laube and Farrell, 2002). It is important that the appropriate antibacterials, antiseptics and dressings are used depending on the severity of the clinical presentation and resistance patterns. Anecdotal evidence indicates that, in the community, leg ulcer infections are common, particularly as many people have hard-to-heal leg ulcers that have persisted over a long period of time. Silver dressings might be useful in such situations, but these are expensive and not always effective (Hussey et al, 2019). Laboratory tests, such as skin swabs, to identify the specific pathogen can take time, and the results might represent colonisation rather than infection of the skin.
Cellulitis (Figure 1) should be clinically distinguished from erysipelas and necrotising fasciitis (Laube and Farrell, 2002). Necrotising fasciitis is a life-threatening condition, which would require surgical debridement of the infected tissue in the majority of cases. Blisters and honey-coloured crusts are typical features of impetigo, which is a very contagious infection, and close patient contacts should, therefore, also be examined for this.
Figure 1. Cellulitis on the leg of a man with type 2 diabetes
Folliculitis is also a common skin infection, often responding well to the use of antiseptics and topical antibacterials. More severe pustular skin eruptions, such as furunculosis and carbunculosis, would normally need treatment with systemic antibacterials (Laube and Farrell, 2002). Intertrigo and erythrasma are infections commonly found among the body folds, especially the axillae and groin, and topical therapy, such as fusidic acid, is usually appropriate and sufficient (Metin et al, 2018; British National Formulary (BNF), 2020).
Persistent pruritus is associated with increasing dryness of the ageing skin (Palmer, 2020). If left untreated or treated unsuccessfully, it can in time result in secondary skin infections. Emollients and antihistamines are useful to treat pruritus. In any person with a skin condition, primary cutaneous disorders and systemic diseases should be excluded with the help of the appropriate investigations, for example, through blood tests and skin biopsy.
Difficulties in diagnosis of skin infections
Recently, Gbinigie et al (2019) carried out research focusing on the difficulties with diagnosing skin infections in older adults throughout the primary care system. The authors noted that older adults with bacterial skin infections may present with atypical symptoms, which makes diagnosis difficult. There is limited authoritative guidance on how older adults in the community present with bacterial skin infections, Gbinigie et al (2019) noted. To date, there have been no systematic reviews assessing the diagnostic value of symptoms and signs in identifying bacterial skin infections in older adults in the community (Gbinigie et al, 2019).
The authors searched Medline and Medline, Embase and Web of Science, from inception to September 2017, and included cohort and cross-sectional studies assessing the diagnostic accuracy of symptoms and signs in predicting bacterial skin infections in adults in primary care older than 65 years. They used the QUADAS-2 tool to assess study quality.
From their research, Gbinigie et al (2019) identified two observational studies of low-moderate quality, with a total of 7991 participants, which provided data to calculate the diagnostic accuracy of five unique symptoms in predicting bacterial skin infections. The presence of wounds, pressure ulcers and skin ulcers were identified as useful for diagnosing bacterial skin infections, and the presence of urinary incontinence was not found to help or predict bacterial skin infections. The authors did identify that it was a limitation of their research that only low-to-moderate quality studies were available for their analysis of the available literature.
The fact that wounds, pressure ulcers and skin ulcers were all found to be predictors of skin infection would seem intuitive, as each presents a portal of entry for bacteria (Gbinigie et al, 2019). Incontinence was not found to help in predicting skin infection, and the authors hypothesised that this could because skin hygience receives more attention in those with incontinence. Another theory is that urine has an anti-bacterial effect due to its urea content, but Gbinigie et al (2019) acknowledged that more high-quality research would be required to confirm or refute this.
Gbinigie et al (2019) also recognised that there is no single gold standard test for diagnosing skin infections, and that clinicians tend to combine clinical assessment with tests (such as cultures). Incorporation bias is, therefore, difficult to avoid and may have led to an overestimation of the accuracy of a given index test, as a symptom or test in isolation is usually unlikely to be sufficient to rule in or out a diagnosis of skin infection.
Conclusion
There appears to be insufficient evidence to inform the diagnosis of bacterial skin infections in older adults in the community. Therefore, clinicians should rely on their clinical judgement and experience. Evidence from high-quality primary care studies in older adults, including studies assessing symptoms that are usually associated with bacterial skin infections (e.g. erythema and warmth), are urgently required to inform practice. It is vital that nurses know whom they can communicate with where a skin infection is suspected, so a treatment modality can be considered right away to avoid further complications, where safe and appropriate, and a culture can be done immediately. For this to be possible, the assessing nurse needs to have the knowledge and skills to recognise the signs of infection of the skin, across various parts of the body, and it would be especially important to also be able to recognise the deadlier skin infections, such as necrotising fasciitis, as this would be more of an emergency whereby surgery may be required.
KEY POINTS:
- Skin conditions are prevalent among older adults, with evidence that almost all residents of care homes have at least one dermatological diagnosis
- These include various skin infections, such as cellulitis and folliculitis
- Diagnosis of skin infections is complex, but there are some indicators of infected skin, such as warmth of the affected area, redness and oozing
- Knowledge and experience in identifying signs and symptoms, as well as communication with the wider team are important
- Common predictors of skin infection include wounds, pressure ulcers and skin ulcers (portal entry for bacteria)
CPD reflective practice:
- List the main symptoms and signs of infection of the skin, as well as common predictors of skin infection
- Reflect on how you best managed a patient with a skin infection, from recognising the infection, assessing and testing and treating, alongside whom you communicated with in the wider team to get the best outcomes for the patient
- What are the main severe and possibly life-threatening skin infections and how you would manage a situation where you have identified signs of one of these in a patient?