itch with a cutaneous eruption and itch without any skin signs. These two categories are listed in Tables 1 and 2, respectively.

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1 abstract SKIN DISEASE An Approach to the Itchy Older Adult Siobhan Ryan, MD, FRCPC, Dermatology Daycare & Wound Healing Centre, Women s College Campus, Sunnybrook & Women s College Health Sciences Centre, Toronto, ON. Itch in the older patient is a common complaint, and one that must be approached in a systematic manner to determine the etiology. Deciding if the itchy older patient fits into one of two categories itchy with a rash, versus itchy without a rash will often help to establish the cause of the pruritus. Endogenous causes as well as exogenous causes of pruritus must be considered. Management depends on the etiology; however, regardless of the cause, control of xerosis and general skin care practices will help alleviate some of the distress of pruritus, especially in the aging population. Key words: pruritus, itch, aging, skin assessment, scratching. The itchy older adult represents a complex and somewhat convoluted path to diagnosis, and management may not always be that satisfying to the patient. However, there are a number of steps that can be followed in order to determine the etiology of pruritus in the older patient. A systematic approach to managing pruritus may lead to good symptomatic control, depending on the cause. Pruritus, like pain, is a subjective and multifaceted symptom that can be affected by emotional, physiologic, environmental, cognitive and social factors, as well as comorbid illness and medications. 1 These features must be kept in mind throughout the assessment of the pruritic patient. Pruritus can be approached in a manner similar to pain assessment. Determining the extent and distribution of the itch, the daily and nightly fluctuations in intensity, and the factors that aggravate or alleviate the itch may suggest, to some extent, the etiology. A scale similar to pain scales can be used to evaluate the intensity of pruritus. Questionnaires can be used to evaluate the specific features of a patient s itch. 2 Based on clinical findings, the itchy older adult can be divided into two categories, depending on the clinical presentation: itch with a cutaneous eruption and itch without any skin signs. These two categories are listed in Tables 1 and 2, respectively. Pruritic Skin Eruptions Seen in Older Adults Those patients with a pruritic skin eruption tend to have a primary skin disease that is itchy, whereas those patients that are itchy without a rash are more likely to have a systemic cause of their pruritus. Itchy patients constantly scratch and pick, leaving numerous excoriations and crusted lesions that may mislead the clinician to think that the problem is one of a crusted or vesiculobullous disorder. However, the distribution of lesions, in accessible areas only, is often a clue to distinguish those eruptions that are related to the trauma of scratching. Crusted lesions on the upper back only, with sparing of the scapular regions, indicate that only those areas that can be reached are scratched, leaving other itchy areas free of skin lesions (Figures 1 and 2). Xerosis in the older adult is probably the most common cause of itch. Although patients with dry skin and pruritus may show a paucity of clinical signs, a history of aggravation of the symptoms in the winter and improvement with emollients will help to make the diagnosis. Xerosis may develop into asteatotic eczema, which is frequently found in the older adult, and may be limited to the lower legs. This would improve with medium-strength topical steroids and skin care routines that minimize dryness. Management of peripheral vascular disease, including arterial insufficiency and venous stasis disease, may improve the pruritus that occasionally accompanies these disorders of the lower extremities. Atopic dermatitis and contact dermatitis will both present as localized areas of itch associated with inflammatory skin changes. If these diseases are suspected, and the patient is not itchy, an alternative etiology of the condition should be considered. There are a number of products available to control the inflammatory component of atopic dermatitis, topical steroids being the most common, but there is no specific agent that addresses the pruritus of this condition GERIATRICS & AGING March 2004 Volume 7, Number 3

2 Table 1: Cutaneous Diseases Associated with Pruritus in Older Adults Disorder Specific Examples Comments Management Inflammatory atopic dermatitis Xerosis may also be a factor in topical steroids contact dermatitis the itchy older patient with if contact, eliminate offending asteatotic eczema these conditions agent psoriasis routine skin care Xerosis Dry rough skin, more Seasonal and environmental emollients prominent on lower aggravation decrease bathing extremities and back routine skin care Neurodermatitis prurigo nodularis May have a psychological Wide variety of treatments designed lichen simplex chronicus factor that impacts on to address all components of these anogenital pruritus recurrences disorders Papulonodular Lichen planus (LP) Rule out lichenoid drug Topical steroids, reaction in LP plus many other modalities Vesiculobullous bullous pemphigoid (BP) Biopsy to confirm diagnosis, Treatment is disease-specific, dermatitis herpetiformis immunofluorescence (IF) but in the case of BP topical pemphigus foliaceous may be necessary therapies may be all that pemphigus vulgaris is needed linear IgA disease Infection/Infestation tinea corporis Specific diagnosis can usually be Specific disorder can usually be candidal infection determined by potassium managed topically, pruritus folliculitis hydroxide (KOH), swab for culture may persist after adequate scabies and sensitivity, visualization of treatment, especially in scabies pediculosis offending organism or biopsy pin worms insect bites Drug reactions Multiple cutaneous Exanthematous is most common eliminate the medication presentations, including routine skin care pruritus without a rash Urticarial urticaria UV may be itchy, painful Etiology must be determined urticarial vasculitis (UV) or burning for Rx Miscellaneous diabetic dermopathy tend to be more localized Treat the disorder and add lichen sclerosis may need biopsy for diagnosis topical steroids, menthol, macular and lichen amyloidosis praxomine, camphor, topical miliaria doxepin, topical immunomodulators papular urticaria prurigo simplex Miscellaneous Grover's disease (TAD) biopsy will be necessary Treatment is disease-specific mycosis fungoides to confirm diagnosis mastocytosis Psoriasis is an inflammatory skin condition that historically has not been associated with itch; however, in a recent study 84% of patients with extensive psoriasis complained of generalized pruritus that impacted quality of life. 4 The severity of the psoriasis did not always correlate with the intensity of the itch, 5 a phenomenon seen in many other pruritic disorders. Prurigo nodularis, lichen simplex chronicus, neurodermatitis and anogenital pruritus are all conditions in which the itch is quite disabling to patients, and the clinical findings are often limited relative 49

3 Table 2: Diseases Associated with Pruritus with Little or No Skin Changes in the Older Adult Disorders Specific Examples Comments/Management Gastrointestinal/hepatic primary biliary cirrhosis routine skin care biliary obstruction phototherapy Renal uremic pruritus routine skin care phototherapy Hematologic polycythemia rubra vera (PRV) PRV is described as the bath itch iron deficiency anemia and sometimes is mistaken for leukemia/lymphoma aquagenic pruritus eosinophilia mycosis fungoides 19 Infection/Infestations hepatitis B, C history will aid the diagnosis HIV CJD disease prion pruritus 20 Creutzfeldt-Jacob disease (CJD) post-herpetic neuralgia may be post-herpetic neuralgia burning, painful or itchy Malignancy/Solid tumours breast, gastric and lung Routine investigations only Endocrine thyroid disease Blood work required diabetes Drug reaction Usually associated with a skin eruption Careful and prompt history Localized pruritus notalgia paresthetica scapular area brachioradial pruritus forearm area Psychiatric itch secondary to chronic anxiety/depression May lead to neurotic excoriations or delusions of parasitosis dermatitis artifacta Miscellaneous cutaneous mastocytosis History and/or skin biopsy would be required aquagenic pruritus to establish diagnosis sarcoidosis 21 carcinoid syndrome multiple sclerosis to the degree of discomfort described by the patient. All four conditions fall into the itch-scratch-rash category of skin conditions. The more scratching, picking and rubbing that is done, the worse the itch and often the most significant the resulting rash. Management is often directed at trying to stop this itch cycle. The longterm prognosis of these conditions varies greatly from patient to patient, as a psychological component such as anxiety, stress or depression may play a role in aggravation of their disease. When faced with a patient with anogenital pruritus, the possibility of lichen sclerosis, candida infection or psoriasis also should be considered. Lichen planus is a violaceous papular eruption that is usually symmetrical, and commonly found on the extremities. It is often intensely itchy and the etiology is unknown, except in cases of drug-induced lichen planus, more correctly called lichenoid drug eruption. Medications commonly implicated in this disorder are gold salts, non-steroidal anti-inflammatory agents, allopurinol, angiontensin-converting enzyme (ACE) inhibitors, ketoconazole, methlydopa and penicillamine. 5 The firstline therapy of idiopathic lichen planus includes topical steroids, although many other topical and systemic products may be required to control the pruritus of this condition. Patients presenting with pruritus and evidence of a vesiculobullous eruption would benefit from a skin biopsy to determine the etiology of their disease. Bullous pemphigoid is a not uncommon itchy condition in the older patient. Management of bullous pemphigoid includes topical steroids for localized disease, and oral prednisone for more generalized or difficult to control disease. In patients for whom the risks of oral steroids are too great or contraindicated because of comorbid illnesses, tetracycline plus nicotinamide 6 may be of benefit, or azathioprine can be used. Drug eruptions commonly present as maculopapular symmetrical, general- 50 GERIATRICS & AGING March 2004 Volume 7, Number 3

4 ized eruptions that are commonly itchy. Drug eruptions as a cause of generalized pruritus, without cutaneous features, have been described. 7 One of the more notable medications that may lead to generalized pruritus is chloroquine when used in patients with malaria. 8 Drug reaction should be considered in the itchy older adult. A careful history of medication and the onset of the pruritus is essential to the diagnosis of a pruritic drug eruption. Tinea corporis may or may not be itchy, and may be localized or generalized. A certain degree of suspicion must be considered in patients with a scaly erythematous eruption in fairly well circumscribed plaques and patches. Skin scraping for fungal culture would aid in the diagnosis. Intertriginous candida may be itchy, or may be associated with a burning discomfort. It must be distinguished from intertriginous psoriasis. Infestation with the scabies mite is probably one of the most pruritic eruptions that a patient will experience. Many patients will present with numerous excoriations, as well as small papules around the wrists, axillae, waist line and groin. However, primary skin lesions may be rare, and the itch intense. In nodular scabies, the patient may have only one or a few reddish-purple itchy nodules usually in the groin or axillary region. Scabies in the older patient may have very few cutaneous signs, or the features may be atypical. Scabies in long-term care facilities may go undetected, especially if the initially infected individual is cognitively impaired leading to spread of the mite to other patients as well as staff. There are many other cutaneous disorders that may be associated with pruritus. The list includes transient acantholytic dermatosis (Grover s disease), prurigo simplex, papular urticaria, miliaria rubra and folliculitis. These disorders are less common than those discussed above; however, the histology of these conditions would help in the diagnosis, and then management would be directed at the specific etiology in each case. Other pruritic skin conditions that may have systemic features include cutaneous T-cell lymphoma (mycosis fungoides), mastocytosis and diabetic dermopathy. The history and physical examination will help in the diagnosis of these disorders, as well as the histopathology. Pruritus Without Cutaneous Features in the Older Adult Uremic pruritus represents a significant problem for patients with end-stage renal disease. The actual incidence of pruritus in these patients varies. It may be present in patients before they are candidates for dialysis, and the BUN and creatinine levels do not correlate with the degree of itch. Dialysis patients generally have drier skin than age- and sex-matched controls, and maintenance of good skin hydration with emollients has been shown to be of benefit in reducing their pruritus. 9 Approximately 20% of patients with widespread pruritus without cutaneous findings will be found to have a systemic disease. 10 Patients with generalized pruritus and no apparent cause are sometimes suspected of having an associated solid tumour malignancy. However, the incidence of solid tumour malignancy among these patients has not been shown to be any greater than that of the general population. 11 History and physical as well as the routine investigations done for generalized pruritus would be adequate to rule out this possibility. Generalized pruritus as a manifestation of lymphoma or leukemia has been well described, especially in Hodgkin s lymphoma. 12 In the older itchy adult who presents with generalized pruritus without a rash and shows no improvement with management of xerosis, investigations that should be done include CBC, eosinophil count, ferritin level, immunoelectrophoresis, plasma protein electrophoresis, urinalysis, stool for ova and parasites and occult blood, CXR, liver function, renal function and thyroid function. Confirmation of current or past infection with hepatits B, C or HIV may, at times, be relevant, depending on the Figure 1. Excoriations in a patient with generalized pruritus with scapular sparing of the skin lesions. Only those areas that the patient can reach are scratched. past medical history of the patient. Management of Pruritus Management of pruritus begins with establishing the underlying cause. Treatment will then depend on the type of itch that is present. Evaluation of the benefit of anti-pruritic agents is difficult to assess. A placebo effect has been shown to be as high as 50% in some itchy patients, 13 making interpretation of results difficult. Histamine release is related to itch in pruritic conditions such as in insect bites and certain types of urticaria. H1 antihistamines should work well in these two Figure 2. Excoriations in generalized pruritus with no primary skin lesion present. 51

5 conditions; however, in other pruritic disorders in which histamine is not involved, H1 antihistamines are only of benefit for their sedating effect. In the itchy older adult, the sedation may not be a desired effect. In non-histamine associated itch, the benefit of the non-sedating antihistamines is doubtful. 14 The tricyclic antidepressant, doxepin, is used for generalized pruritus again because of its antihistamine effect, but this also is associated with the side effect of sedation. Topical doxepin can be used, but with caution, as there is an associated systemic absorption of this compound leading to sedating effects with this topical product. 15 Topical steroids do not have a direct antipruritic effect; however, these products may lead to disease control in inflammatory skin conditions and therefore diminish itch. Topical tacrolimus and pimecrolimus as well do not reduce itch, but may reduce inflammation in eczema and, in the same manner as topical steroids, may lead to symptomatic improvement in pruritus. Routine skin care to reduce dryness should help reduce a component of pruritus, regardless of the cause. Products such as topical capsaicin, 16 pramoxine, phenol, camphor and menthol 17 may be useful in localized intense pruritus, and may be found in an emollient base or formulated with topical steroids. If used on an inflammatory skin condition, the local irritant effect of capsaicin may be greater than the antipruritic effect, 18 although this adverse effect is meant to diminish over time with use of the product. Intralesional steroids are used on the thickened and lichenified pruritic lesions seen in prurigo nodularis or lichen simplex chronicus. Phototherapy, either ultraviolet B (UVB) or psoralen-ultraviolet A (PUVA), has been shown to be effective in relieving pruritus due to a wide variety of etiologies, including: atopic dermatitis, psoriasis, xerosis, prurigo nodularis, lichen simplex chronicus, lichen planus, prurigo simplex, lichen amyloidosis and diabetic dermopathy. Generalized pruritus related to uremia, cholestasis, hepatitis C, HIV disease and lymphoma respond mainly to UVB. Phototherapy may be a reasonable alternative in the itchy older adult on multiple medications, and with various comorbid illnesses. Conclusion Pruritus, whether localized or generalized, represents a symptom that is often very distressing to the patient. The etiology of the pruritus needs to be determined in order to attempt to successfully treat this problem. Careful history, physical examination and investigations directed at finding the etiology are all important in the assessment of the itchy older adult. Management is often disease-specific and attempts to address the underlying cause of the pruritus. Side effects, especially sedation, must be considered in the choice of treatment for the itchy older adult. No competing financial interests declared. References 1. Holdcroft A, Power I. Management of pain. BMJ 2003:326; Yosipovitch G, Ansari N, Goon A, et al. Clinical characteristics of pruritus in chronic idiopathic urticaria. Br J Dermatol 2002;147: Wahlgren CF. Itch and atopic dermatitis: an overview. J Dermatol 1999;26; Yosiovitch G, Goon A, Wee J, et al. The prevalence and clinical characteristics of pruritus among patients with extensive psoriasis. Br J Dermatol 2000:143: Halevy S, Shai A. Lichenoid drug eruptions. J Am Acad Dermatol 1993;29: Kolbach DN, Remme JJ, Bos WH, et al. Bullous pemphigoid successfully controlled by tetracycline and nicotinamide. Br J Dermatol 1995;133: Bigby M, Jick S, Jick H, et al. Drug-induced cutaneous reactions. A report from the Boston Collaborative Drug Surveillance Program on 15, 438 consecutive inpatients, 1975 to JAMA 1986; 256: Osifo NG. Chloroquine-induced pruritus among patients with malaria. Arch Dermatol 1984;120: Morton CA, Lafferty M, Hau C, et al. Pruritus and skin hydration during dialysis. Nephrol Dial Transplant 1996;11: Zirwas MJ, Seraly MP. Pruritus of unknown origin: A retrospective study. J Am Acad Dermatol 2001;45: Paul R, Paul R, Jansen CT. Itch and malignancy prognosis in generalized pruritus: a 6 year follow-up of 125 patients. J Am Acad Dermatol 1987;16; Urba WJ, Longo DL. Hodgkin s disease. N Engl J Med 1992;326: Hagermark O, Wahlgren CF. Treatment of itch. Semin Dermatol 1995:41: Klein PA, Clark RA. An evidence-based review of the efficacy of antihistamines in relieving pruritus in atopic dermatitis Arch Dermatol 1999;135: Smith PF, Corelli RL. Doxepin in the management of pruritus associated with allergic cutaneous reactions Ann Pharmacother 1997;31: Lysy J, Sistiery-Ittah M, Israelit Y, et al. Topical capsaicin--a novel and effective treatment for idiopathic intractable pruritus ani: a randomised, placebo controlled, crossover study. Gut 2003;52: Burkhart CG, Burkhart HR. Contact irritant dermatitis and anti-pruritic agents: the need to address the itch. J Drugs Dermatol 2003;2: Tolster-Holst R, Brasch J. Effect of topically applied capsacin on pruritus in patients with atopic dermatitis. J Dermatol Treatment 1996;7: Pujol RM, Gallardo F, Llistosella E, et al. Invisible mycosis fungoides: A diagnostic challenge. J Am Acad Dermatol 2002;47(2 Suppl):S Shabtai H, Nisipeanu P, Chapman J, et al. Pruritus in Creutzfeldt-Jacob disease. Neurology 1996;46: Kligman AM. The invisible dermatoses. Arch Dermatol 1991;127: GERIATRICS & AGING March 2004 Volume 7, Number 3