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Scabies are your patients at risk?
SCABIES ARE YOUR PATIENTS AT RISK?
Often difficult to diagnose, scabies can imitate other disorders and infest many. LEE M. HOOD Outbreaks of scabies infestations have increased in the United States since the early 1970s, affecting all socioeconomic groups and involving hospitals as well as extended care facilities(I,2). Its incidence fluctuates cyclically throughout the world, although not all parts of the globe are simultaneously in the same phase of the cycle. It is believed that epidemics of scabies occur in 30-year cycles with a 15-year gap between the end of one epidemic and the beginning of the next. Some authorities believe the current pandemic is extending Lee M. Hood, RN, MA, CIC, is an infection control nurse at the Veterans Administration Medical Center, Phoenix, AZ. The author wishes to acknowledge the help of Jean Crosier, MLS, and Christine Hempsey, RN.
beyond the 15-year period, although the reasons for this are unc!ear(3). Belle and others described one of the most dramatic examples of an outbreak involving two hospitals in Ontario, Canada, which subsequently affected 700 individuals. The index case (source) was found to be an elderly female who had visited California three months earlier(4). In a California community hospital, an 89-year-old woman was the index case in an outbreak that eventually encompassed 107 individuals. Those affected included 10 other patients and 4 members of their families and 66 employees and 27 members of their families. The estimated cost of the outbreak was $25,000(5). Parish and others reported a scabies outbreak involving three extended care facilities, two in Missouri and One in Pennsylvania(6). The authors discussed the difficulty encountered in the diagnosis and eradication Of these "microepidemics." Another .report discussed an intermediate care facility in West Virginia that had repeated problems with infestations of scabies among patients
312 Geriatric Nursing November/December 1987
and staff(7). To better understand this skin disease and, if necessary, manage an outbreak, let us take a closer look.
History Scabies has had a fascinating history dating back to the Egyptians, Greeks, and Romans. James VI of Scotland (also known as James I of England) is said to have declared that only kings and princes should have the itch because the sensation of scratching is so delightful(8). It is common folklore among dermatologists that Napoleon Bonaparte had scabies and was scratching when. he posed for that famous portrait with one hand in his coat(9). In fact, scabies is the first human disease to have an identified cause. Bonomo made the initial association after discovering the itch mite in 1687(3). Nevertheless, many physicians refused to believe that scabies was caused by a mite and as late as 1865, Hunt emphatically declared that scabies was caused by dirt alone(8). Most debate ended in 1864, how-
ever, when Simon Renucci, a Corsican physician, demonstrated the cause and effect ofthe mite to a large, skeptical audience of medical notables at l'Hopital St. Louis in Paris. The impact of his presentation can only be appreciated if one realizes that possibly 60 percent of all skin diseases occurring in Europe at that time could beattributed to the scabies mite(10).
DIFFERENTIAL DIAGNOSIS FOR SCABIES AND PEDICULOSIS
Type
Symptoms
Affected Areas
Classic
Pruritus; burrows; symmetric eruptions or rod papules; vesicles or pustules; crusted lesions; nodules; eczematous patches
Nodular
Reddish-brown pruritic bumps
Hands (finger webs and sides of digits); flexor surface of the wrist; extensor surface of the elbow; abdomen (around umbilicus); female breasts; penis; scrotum; buttocks Thin areas of the skin (such as axillae and groin)
Scabies in the clean
Same as classic Pruritus; small, indistinct lesions; few burrows Hands; feet; ears; Hyperkeratotic under nails and lesions scalp; head
Biology Scabies is an infectious, pruritic skin disease caused by an almost microscopic mite (Sarcoptes scabieO, requiring relatively constant contact with human skin. Commonly known as the "itch mite," its name is well chosen, because one of the leading symptoms is itching, especially during the night. The adult mite has a flattened, translucent body roughly resembling a turtle in shape. With eight legs instead of six, the mite is more closely related to spiders and ticks than to insects. The female is about .33-ram long and twice the size of the male, who impregnates the female on the surface of the skin and then dies within 2 days. During her 30-day life span, the female mite lays two to three eggs per day, which progress through larval and nymphal stages to form adult mites within 10 days. In the meantime, the female digs a permanent burrow into the stratum corneum epidermis (dead, horny skin layer). There, it feeds on intracellular lymphlike fluid rather than blood, because capillaries do not reach into the epidermal layer. The mite can travel across the skin surface on the ~verage of one inch per minute and !ends to live in skin folds or creases in :he axillae, waist, groin, elbows, mees, and soles of the feet(l 1-13).
Social conditions that promote the transmission of scabies include war, sexual promiscuity, overcrowding, and increased mobility of the population. The elderly and the immunosuppressed are considered to be at high risk for contracting this disease. Evidence also suggests that scabies occurs with less frequency among black Americans than among white Americans(13).
~pidemiolog'y
Diagnosis
For scabies to be transmitted, skino-skin contact is necessary. While nfected clothing and bed linen are are but possible sources, inanimate .bjects (fomites) play an insignifiant role in transmission of the mite. )he researcher stated that transmis[on via fomites occurred in about 1 1 200 cases(14).
In order to make a definitive diagnosis of scabies, one must identify either the mite, eggs, or fecal pellets (scybala). One can make a presumptive diagnosis of scabies if burrows are identified, but these may be difficult to find. There are several methods for locating burrows. Applying mineral oil on the skin surface allows
Norwegian (crusted)
Pediculosis
Head; pubic area; hairy parts of the body; body lice are found in seams of
Pruritus
Distinguishing Characteristics 4 to 6 weeks for pruritus rash to intensify
Same as classic; 7% of infected individuals have this variation Same as classic Thousands of mites; predominantly in those with mental or physical disability or immunodeficiency; most contagious form Nits are visible and cling to hair shaft
clothing
for better visibility of the burrows, especially on dry, scaly areas such as the elbows. Another diagnostic method is the burrow ink test. A fountain pen with blue or black ink is rubbed on suspected burrows. The surface ink is then wiped off with an alcohol pad, while the remaining ink penetrates the burrow and highlights its path. The burrow should be shaved off with a scalpel and microscopically examined for the mite and its products(ll). A more time-consuming method involves the use of a tetracycline preparation applied to the suspected skin surface, which is wiped clean with alcohol and then viewed under a Wood's light for fluorescent staining of the burrows. In all cases, it is recommended to first scan the skin with a magnifying
G e r i a t r i c Nursing_ Noveml,q, rff'x,~,~,,,,~-,--)'~o--a " "
glass under sufficient illumination. An individual adept at scabies identification can usually locate the mite at the end ofthe burrow with little more than a No. 11 scalpel blade. It is generally recommended to place a drop of mineral oil on the burrow and/or suspected lesions and gently scrape or superficially shave the area. This debris should then be placed on a glass slide where it can be examined with a microscope.
scabies or lice, the terms may seem synonymous. However, there is a distinct difference between them. Lice (pediculosis), whether head or pubic, can be seen with the naked eye and, except for a few scratch marks from itching, do not produce a rash. The pruritus associated with this condition occurs in the hairy parts of the body. One telltale clue is the presence of nits, the eggs of lice. At first glance,
Crusted areas in Norwegian scabies harbor large numbers of mites in all stages of development, making this the most contagious form of scabies.
body, the host is relatively unaware of what is happening. It is not until immunologic reactivity develops that the host becomes acutely aware of the problem(9). Because of the length of time required for a significant number of papules to develop, diagnosis is very difficult as is identification of the index case. With shortened hospital stays, the patient is frequently discharged before the nursing staff or other patients show signs of infestation. If one should be reexposed within six to eight months after the primary infestation, the pruritus and eruptions will begin within 48 to 72 hours because of the prior sensitization. Atypical Scabies
Unfortunately, the yield of skin scrapings or shavings is not 100 percent. Two experienced authorities claim a 60 percent recovery rate of the mite in suspected scabies cases(3). If the individual suspected of having scabies gives a history of close contact with people having similar pruritus and lesions, an attempt should be made to obtain a positive scraping from them. Once the positive finding of a mite or its products are found in one individual, those in close contact with this person should also be treated. Classic Scabies
Because scabies runs a close second to syphilis as being a great imitator of other skin conditions, it is often difficult to diagnose(l). Even if one is familiar with classic scabies, it can be easily misdiagnosed because its main symptom, pruritus, has many causes. For example, the elderly frequently have dry, flaky skin, a common cause of pruritus. Unless one is on the alert, scabies will not be part of the differential diagnosis. Pruritus will occur throughout the day but intensifies at night. Coupled with this is one or more of the following: burrows, symmetric eruptions of red papules (often excoriated), vesicles or pustules, crusted lesions, nodules, and eczematous patches(12). For a nurse who has never seen
the eggs look like small white particles resembling dandruff, however, upon closer inspection they are uniformly oblong in appearance and cling to the hair shaft. Removal of these irritating creatures is quite difficult and time-consuming. In contrast to pediculosis, scabies appears primarily as skin eruptions on the hands of infected individuals. With time, the hand lesions resemble eczema a n d appear on the finger webs and sides of the digits. Other areas of involvement are the flexor surface of the wrist; extensor surface of the elbow; the abdomen, especially around the umbilicus; female breasts; the penis and scrotum; and the buttocks(l l). One rule of thumb is to look in areas of clothing constriction such as the waist, wrist, bra line, and crotch. In bedridden patients, the lesions may be isolated on the back or other skin surfaces that are in constant contact with the sheets. When a person first becomes infected with scabies there may be a slight irritation at the site of the burrow, but it takes four to six weeks for the pruritus to intensify and the rash to develop. It is generally accepted that the itching of scabies represents a host T-cell-mediated immunologic response. Dtifing the early phase of infestation, when the organism is burrowing and traveling over the
314 Geriatric Nursing November/December 1987
Nodular scabies, "scabies in the clean," and Norwegian (crusted) scabies are several manifestations of the atypical form of the skin disorder. Nodular lesions are seen in about l out of 15 cases and present as reddish-brown pruritic bumps. They are found primarily on the covered thin areas of the skin such as the axillae and groin and may persist for several months(12). Scabies in the clean is found in habitually clean individuals. In the process of bathing or scratching, the mites are removed from the surface of the skin. When lesions are present, they are small and indistinct with very few burrows, making diagnosis difficult. In contrast, there are thousands of mites in individuals who have Norwegian scabies. This rare variant, caused by the same mite that causes classical scabies (Sarcoptes scabiet), occurs predominantly in those with mental or physical disability or immunodeficiency(12). With the current widespread use of immunosuppressive agents, crusted scabies is increasingly seen in immunocompromised patients. Despite the abundance of mites, itching is rarely a presenting symptom, probably because of the inability of the infested individual to develop an appropriate immune response. As the name implies, an individual with crusted scabies has hyperkeratotic (crusted) lesions, which appear
on the hands, feet, ears, and under the nails and scalp. Unlike classical scabies, lesions are found on the head as well. Because the crusted areas harbor large numbers of mites in all stages of development, it is the most contagious form of scabies. Unsuspecting caregivers who apply lotion or bathe affected individuals are at great risk of contracting the disease. There have been numerous instances of local epidemics of scabies originating from a single case of crusted scabies(l 5). When scabies is contracted from someone with crusted scabies, it will have the classical manifestations rather than the crusted appearance.
Animal Scabies The question that sometimes arises is whether animal scabies can be transmitted to humans. The answer is yes. Dogs and cats are the two kinds of animals most commonly cited as scabies carriers, with puppies in particular being implicated in transmission. The mite of canine scabies (Sarcoptes scabiei var. canis) is morphologically similar to the mite of human scabies. The condition it causes in dogs is Usually referred to as mange. It appears that the canine mite feeds on human skin but does not propagate itself on the human host. Therefore, no burrows will be discovered. Removal of the dog will quickly lead to an eradication of the skin eruptions(16). It is advisable to closely examine any dogs for skin disease, especially when they are used for pet therapy in health care facilities. To a lesser degree, cats have also been implicated in causing scabies-like eruptions in humans. In those cases, mites are usually found in the cat's ears.
Treatment The treatment of choice for scabies is I% gamma benzene hexachloride lotion or cream (Kwell). Before applying the lotion or cream to the entire skin surface from the neck down, the infected individual should take a warm bath or shower and then let the body cool for approximately 10 minutes. It is important t o apply this medication (1 ounce of Kwell is
usually sufficient for an adult) to all skin surfaces including the nails, body creases, and folds--unaffected as well as affected areas. A second person is usually needed to apply the medication to the back. After leaving Kwell on for 8 to 12 hours, a thorough washing (either a bath or shower) is necessary. This should be followed with freshly laundered clothes, clean bed linens, and a thoroughly cleaned bath tub or shower stall. One application usually suffices. Asymptomatic contacts should be treated concurrently. It must be emphasized that individuals who have been successfully treated may continue to complain of itching for several weeks after treatment, due to the hypersensitivity to the debris left in the burrows from the mites. Do not apply additional Kwell unless unsuccessful treatment can be demonstrated by the development of new papules and burrows. A second medication used primarily for children or pregnant women is crotamiton (Eurax) cream or lotion. This preparation is less toxic and should be left on for 24 hours. Some physicians recommend a second application of Eurax 24 hours after the first application without bathing in the interim.
Nursing Care Because the elderly sometimes overreact to pruri{us by producing erythema and scaling, diagnostic features of scabies are often masked(6). This may be related to an underlying dry skin condition aggravated by the use of soap. The following are preliminary guidelines: • Perform an initial thorough assessment of the skin condition of all new admissions; repeat at periodic intervals so any change can be noted as soon as possible. • Know what scabies looks like; obtain a good dermatologic reference so comparisons with colored pictures can be made. • Have a hand magnifying glass available to look for burrows. • Learn how to perform skin scrapings; ask a dermatologist to teach you and other members of your nursing staff. Once scabies has been diagnosed
in a patient, the following steps should be taken: • Make a list of all patients and staff who have had close contact with the infected individual and follow protocol for treatment. • Do not overtreat; wear gloves when bathing infested individuals and when applying Kwell; one application of Kwell applied correctly will usually rid the individual of classical scabies. • Change linen and use freshly laundered clothes for all treated individuals. • If a second application is warranted, allow five days to elapse before reapplication. • Beware of pseudooutbreaks; the power of suggestion frequently induces itching--many have received Kwell unnecessarily. • Remember that the elderly and/ or immunocompromised will not always itch as readily as someone whose immune system is intact. • Be on the alert for scabies.
References 1. Orkin, M. Today's scabies. JAMA 233:882-885, Aug. 25, 1975. 2. Shaw, P. K., and Juranek, D. D. Recent trends in scabies in the United States. J.lnfect.Dis. 134:414.-416, Oct. 1976. 3. Orkin, M., and Maibach, H. I. Modern aspects of scabies. Curr.Probl.Dermatol. 13:109-127, 1985. 4. Belle, E.A.,andothers. Hospitatepidemicofscabies: diagnosis and control. Can.J.Public Health 70:133-135, Mar.-Apr. 1979. 5. Cooper, C. L., and Jackson, M.M. Outbreak of scabies in a small community hospital. Am.J.lnfeet.Control 14:173-179, Aug. 1986. 6. Parish, L. C., and others. Scabies in the extended care facility, lnt.J.Dermatol. (Phil.) 22:380-382, July-Aug. 1983. 7. Rideway, W. C.; and others. Treating an unusual outbreak of scabies. TNH 5(11):29-31, Nov. 1984. 8. Alexander, J. O. Scabies and pediculosis. Practitioner 200:632-644, May 1968. 9. Leyden, J. J. More than skin deep. Emerg.Med. 14:126-141, Sept. 30, 1982. I0. Crissey, J. T. Scabies and pediculosis pubis. Urol.Clin.NorthAm. 11:171-176, Feb. 1984. 11. Estes, S. A. The Diagnosis and Management of Scabies. Piscataway, NJ, Reed & Carnrick, 1981. 12. Gurevitch, A. W. Scabies and lice. Pediatr.Clin.North Am. 32:987-1018, Aug. 1985. 13. Orkin, M., and Maibach, H. I. Current views of scabies and pediculosis pubis. Cutis (New York) 33:85-96, Jan. 1984. 14. Alexander, J.O.Scabiesinchildren.Clin.Pediatr. (Phil.) 8:73-85, Feb. 1969. 15. Espy, P. D., and Jolly, H. W. Norwegian scabies: occurrence in a patient undergoing immunosulrpression. Areh.Dermatol. 112:193-196, Feb. 1976. 16. Norins, A. L. Canine scabies in children. "'Puppie dog" dermatitis. Am.J.Dis.Child. !!7:239-242, Feb. 1969.
Geriatric Nursing November/December 1987 315
Often difficult to diagnose, scabies can imitate other disorders and infest many. LEE M. HOOD Outbreaks of scabies infestations have increased in the United States since the early 1970s, affecting all socioeconomic groups and involving hospitals as well as extended care facilities(I,2). Its incidence fluctuates cyclically throughout the world, although not all parts of the globe are simultaneously in the same phase of the cycle. It is believed that epidemics of scabies occur in 30-year cycles with a 15-year gap between the end of one epidemic and the beginning of the next. Some authorities believe the current pandemic is extending Lee M. Hood, RN, MA, CIC, is an infection control nurse at the Veterans Administration Medical Center, Phoenix, AZ. The author wishes to acknowledge the help of Jean Crosier, MLS, and Christine Hempsey, RN.
beyond the 15-year period, although the reasons for this are unc!ear(3). Belle and others described one of the most dramatic examples of an outbreak involving two hospitals in Ontario, Canada, which subsequently affected 700 individuals. The index case (source) was found to be an elderly female who had visited California three months earlier(4). In a California community hospital, an 89-year-old woman was the index case in an outbreak that eventually encompassed 107 individuals. Those affected included 10 other patients and 4 members of their families and 66 employees and 27 members of their families. The estimated cost of the outbreak was $25,000(5). Parish and others reported a scabies outbreak involving three extended care facilities, two in Missouri and One in Pennsylvania(6). The authors discussed the difficulty encountered in the diagnosis and eradication Of these "microepidemics." Another .report discussed an intermediate care facility in West Virginia that had repeated problems with infestations of scabies among patients
312 Geriatric Nursing November/December 1987
and staff(7). To better understand this skin disease and, if necessary, manage an outbreak, let us take a closer look.
History Scabies has had a fascinating history dating back to the Egyptians, Greeks, and Romans. James VI of Scotland (also known as James I of England) is said to have declared that only kings and princes should have the itch because the sensation of scratching is so delightful(8). It is common folklore among dermatologists that Napoleon Bonaparte had scabies and was scratching when. he posed for that famous portrait with one hand in his coat(9). In fact, scabies is the first human disease to have an identified cause. Bonomo made the initial association after discovering the itch mite in 1687(3). Nevertheless, many physicians refused to believe that scabies was caused by a mite and as late as 1865, Hunt emphatically declared that scabies was caused by dirt alone(8). Most debate ended in 1864, how-
ever, when Simon Renucci, a Corsican physician, demonstrated the cause and effect ofthe mite to a large, skeptical audience of medical notables at l'Hopital St. Louis in Paris. The impact of his presentation can only be appreciated if one realizes that possibly 60 percent of all skin diseases occurring in Europe at that time could beattributed to the scabies mite(10).
DIFFERENTIAL DIAGNOSIS FOR SCABIES AND PEDICULOSIS
Type
Symptoms
Affected Areas
Classic
Pruritus; burrows; symmetric eruptions or rod papules; vesicles or pustules; crusted lesions; nodules; eczematous patches
Nodular
Reddish-brown pruritic bumps
Hands (finger webs and sides of digits); flexor surface of the wrist; extensor surface of the elbow; abdomen (around umbilicus); female breasts; penis; scrotum; buttocks Thin areas of the skin (such as axillae and groin)
Scabies in the clean
Same as classic Pruritus; small, indistinct lesions; few burrows Hands; feet; ears; Hyperkeratotic under nails and lesions scalp; head
Biology Scabies is an infectious, pruritic skin disease caused by an almost microscopic mite (Sarcoptes scabieO, requiring relatively constant contact with human skin. Commonly known as the "itch mite," its name is well chosen, because one of the leading symptoms is itching, especially during the night. The adult mite has a flattened, translucent body roughly resembling a turtle in shape. With eight legs instead of six, the mite is more closely related to spiders and ticks than to insects. The female is about .33-ram long and twice the size of the male, who impregnates the female on the surface of the skin and then dies within 2 days. During her 30-day life span, the female mite lays two to three eggs per day, which progress through larval and nymphal stages to form adult mites within 10 days. In the meantime, the female digs a permanent burrow into the stratum corneum epidermis (dead, horny skin layer). There, it feeds on intracellular lymphlike fluid rather than blood, because capillaries do not reach into the epidermal layer. The mite can travel across the skin surface on the ~verage of one inch per minute and !ends to live in skin folds or creases in :he axillae, waist, groin, elbows, mees, and soles of the feet(l 1-13).
Social conditions that promote the transmission of scabies include war, sexual promiscuity, overcrowding, and increased mobility of the population. The elderly and the immunosuppressed are considered to be at high risk for contracting this disease. Evidence also suggests that scabies occurs with less frequency among black Americans than among white Americans(13).
~pidemiolog'y
Diagnosis
For scabies to be transmitted, skino-skin contact is necessary. While nfected clothing and bed linen are are but possible sources, inanimate .bjects (fomites) play an insignifiant role in transmission of the mite. )he researcher stated that transmis[on via fomites occurred in about 1 1 200 cases(14).
In order to make a definitive diagnosis of scabies, one must identify either the mite, eggs, or fecal pellets (scybala). One can make a presumptive diagnosis of scabies if burrows are identified, but these may be difficult to find. There are several methods for locating burrows. Applying mineral oil on the skin surface allows
Norwegian (crusted)
Pediculosis
Head; pubic area; hairy parts of the body; body lice are found in seams of
Pruritus
Distinguishing Characteristics 4 to 6 weeks for pruritus rash to intensify
Same as classic; 7% of infected individuals have this variation Same as classic Thousands of mites; predominantly in those with mental or physical disability or immunodeficiency; most contagious form Nits are visible and cling to hair shaft
clothing
for better visibility of the burrows, especially on dry, scaly areas such as the elbows. Another diagnostic method is the burrow ink test. A fountain pen with blue or black ink is rubbed on suspected burrows. The surface ink is then wiped off with an alcohol pad, while the remaining ink penetrates the burrow and highlights its path. The burrow should be shaved off with a scalpel and microscopically examined for the mite and its products(ll). A more time-consuming method involves the use of a tetracycline preparation applied to the suspected skin surface, which is wiped clean with alcohol and then viewed under a Wood's light for fluorescent staining of the burrows. In all cases, it is recommended to first scan the skin with a magnifying
G e r i a t r i c Nursing_ Noveml,q, rff'x,~,~,,,,~-,--)'~o--a " "
glass under sufficient illumination. An individual adept at scabies identification can usually locate the mite at the end ofthe burrow with little more than a No. 11 scalpel blade. It is generally recommended to place a drop of mineral oil on the burrow and/or suspected lesions and gently scrape or superficially shave the area. This debris should then be placed on a glass slide where it can be examined with a microscope.
scabies or lice, the terms may seem synonymous. However, there is a distinct difference between them. Lice (pediculosis), whether head or pubic, can be seen with the naked eye and, except for a few scratch marks from itching, do not produce a rash. The pruritus associated with this condition occurs in the hairy parts of the body. One telltale clue is the presence of nits, the eggs of lice. At first glance,
Crusted areas in Norwegian scabies harbor large numbers of mites in all stages of development, making this the most contagious form of scabies.
body, the host is relatively unaware of what is happening. It is not until immunologic reactivity develops that the host becomes acutely aware of the problem(9). Because of the length of time required for a significant number of papules to develop, diagnosis is very difficult as is identification of the index case. With shortened hospital stays, the patient is frequently discharged before the nursing staff or other patients show signs of infestation. If one should be reexposed within six to eight months after the primary infestation, the pruritus and eruptions will begin within 48 to 72 hours because of the prior sensitization. Atypical Scabies
Unfortunately, the yield of skin scrapings or shavings is not 100 percent. Two experienced authorities claim a 60 percent recovery rate of the mite in suspected scabies cases(3). If the individual suspected of having scabies gives a history of close contact with people having similar pruritus and lesions, an attempt should be made to obtain a positive scraping from them. Once the positive finding of a mite or its products are found in one individual, those in close contact with this person should also be treated. Classic Scabies
Because scabies runs a close second to syphilis as being a great imitator of other skin conditions, it is often difficult to diagnose(l). Even if one is familiar with classic scabies, it can be easily misdiagnosed because its main symptom, pruritus, has many causes. For example, the elderly frequently have dry, flaky skin, a common cause of pruritus. Unless one is on the alert, scabies will not be part of the differential diagnosis. Pruritus will occur throughout the day but intensifies at night. Coupled with this is one or more of the following: burrows, symmetric eruptions of red papules (often excoriated), vesicles or pustules, crusted lesions, nodules, and eczematous patches(12). For a nurse who has never seen
the eggs look like small white particles resembling dandruff, however, upon closer inspection they are uniformly oblong in appearance and cling to the hair shaft. Removal of these irritating creatures is quite difficult and time-consuming. In contrast to pediculosis, scabies appears primarily as skin eruptions on the hands of infected individuals. With time, the hand lesions resemble eczema a n d appear on the finger webs and sides of the digits. Other areas of involvement are the flexor surface of the wrist; extensor surface of the elbow; the abdomen, especially around the umbilicus; female breasts; the penis and scrotum; and the buttocks(l l). One rule of thumb is to look in areas of clothing constriction such as the waist, wrist, bra line, and crotch. In bedridden patients, the lesions may be isolated on the back or other skin surfaces that are in constant contact with the sheets. When a person first becomes infected with scabies there may be a slight irritation at the site of the burrow, but it takes four to six weeks for the pruritus to intensify and the rash to develop. It is generally accepted that the itching of scabies represents a host T-cell-mediated immunologic response. Dtifing the early phase of infestation, when the organism is burrowing and traveling over the
314 Geriatric Nursing November/December 1987
Nodular scabies, "scabies in the clean," and Norwegian (crusted) scabies are several manifestations of the atypical form of the skin disorder. Nodular lesions are seen in about l out of 15 cases and present as reddish-brown pruritic bumps. They are found primarily on the covered thin areas of the skin such as the axillae and groin and may persist for several months(12). Scabies in the clean is found in habitually clean individuals. In the process of bathing or scratching, the mites are removed from the surface of the skin. When lesions are present, they are small and indistinct with very few burrows, making diagnosis difficult. In contrast, there are thousands of mites in individuals who have Norwegian scabies. This rare variant, caused by the same mite that causes classical scabies (Sarcoptes scabiet), occurs predominantly in those with mental or physical disability or immunodeficiency(12). With the current widespread use of immunosuppressive agents, crusted scabies is increasingly seen in immunocompromised patients. Despite the abundance of mites, itching is rarely a presenting symptom, probably because of the inability of the infested individual to develop an appropriate immune response. As the name implies, an individual with crusted scabies has hyperkeratotic (crusted) lesions, which appear
on the hands, feet, ears, and under the nails and scalp. Unlike classical scabies, lesions are found on the head as well. Because the crusted areas harbor large numbers of mites in all stages of development, it is the most contagious form of scabies. Unsuspecting caregivers who apply lotion or bathe affected individuals are at great risk of contracting the disease. There have been numerous instances of local epidemics of scabies originating from a single case of crusted scabies(l 5). When scabies is contracted from someone with crusted scabies, it will have the classical manifestations rather than the crusted appearance.
Animal Scabies The question that sometimes arises is whether animal scabies can be transmitted to humans. The answer is yes. Dogs and cats are the two kinds of animals most commonly cited as scabies carriers, with puppies in particular being implicated in transmission. The mite of canine scabies (Sarcoptes scabiei var. canis) is morphologically similar to the mite of human scabies. The condition it causes in dogs is Usually referred to as mange. It appears that the canine mite feeds on human skin but does not propagate itself on the human host. Therefore, no burrows will be discovered. Removal of the dog will quickly lead to an eradication of the skin eruptions(16). It is advisable to closely examine any dogs for skin disease, especially when they are used for pet therapy in health care facilities. To a lesser degree, cats have also been implicated in causing scabies-like eruptions in humans. In those cases, mites are usually found in the cat's ears.
Treatment The treatment of choice for scabies is I% gamma benzene hexachloride lotion or cream (Kwell). Before applying the lotion or cream to the entire skin surface from the neck down, the infected individual should take a warm bath or shower and then let the body cool for approximately 10 minutes. It is important t o apply this medication (1 ounce of Kwell is
usually sufficient for an adult) to all skin surfaces including the nails, body creases, and folds--unaffected as well as affected areas. A second person is usually needed to apply the medication to the back. After leaving Kwell on for 8 to 12 hours, a thorough washing (either a bath or shower) is necessary. This should be followed with freshly laundered clothes, clean bed linens, and a thoroughly cleaned bath tub or shower stall. One application usually suffices. Asymptomatic contacts should be treated concurrently. It must be emphasized that individuals who have been successfully treated may continue to complain of itching for several weeks after treatment, due to the hypersensitivity to the debris left in the burrows from the mites. Do not apply additional Kwell unless unsuccessful treatment can be demonstrated by the development of new papules and burrows. A second medication used primarily for children or pregnant women is crotamiton (Eurax) cream or lotion. This preparation is less toxic and should be left on for 24 hours. Some physicians recommend a second application of Eurax 24 hours after the first application without bathing in the interim.
Nursing Care Because the elderly sometimes overreact to pruri{us by producing erythema and scaling, diagnostic features of scabies are often masked(6). This may be related to an underlying dry skin condition aggravated by the use of soap. The following are preliminary guidelines: • Perform an initial thorough assessment of the skin condition of all new admissions; repeat at periodic intervals so any change can be noted as soon as possible. • Know what scabies looks like; obtain a good dermatologic reference so comparisons with colored pictures can be made. • Have a hand magnifying glass available to look for burrows. • Learn how to perform skin scrapings; ask a dermatologist to teach you and other members of your nursing staff. Once scabies has been diagnosed
in a patient, the following steps should be taken: • Make a list of all patients and staff who have had close contact with the infected individual and follow protocol for treatment. • Do not overtreat; wear gloves when bathing infested individuals and when applying Kwell; one application of Kwell applied correctly will usually rid the individual of classical scabies. • Change linen and use freshly laundered clothes for all treated individuals. • If a second application is warranted, allow five days to elapse before reapplication. • Beware of pseudooutbreaks; the power of suggestion frequently induces itching--many have received Kwell unnecessarily. • Remember that the elderly and/ or immunocompromised will not always itch as readily as someone whose immune system is intact. • Be on the alert for scabies.
References 1. Orkin, M. Today's scabies. JAMA 233:882-885, Aug. 25, 1975. 2. Shaw, P. K., and Juranek, D. D. Recent trends in scabies in the United States. J.lnfect.Dis. 134:414.-416, Oct. 1976. 3. Orkin, M., and Maibach, H. I. Modern aspects of scabies. Curr.Probl.Dermatol. 13:109-127, 1985. 4. Belle, E.A.,andothers. Hospitatepidemicofscabies: diagnosis and control. Can.J.Public Health 70:133-135, Mar.-Apr. 1979. 5. Cooper, C. L., and Jackson, M.M. Outbreak of scabies in a small community hospital. Am.J.lnfeet.Control 14:173-179, Aug. 1986. 6. Parish, L. C., and others. Scabies in the extended care facility, lnt.J.Dermatol. (Phil.) 22:380-382, July-Aug. 1983. 7. Rideway, W. C.; and others. Treating an unusual outbreak of scabies. TNH 5(11):29-31, Nov. 1984. 8. Alexander, J. O. Scabies and pediculosis. Practitioner 200:632-644, May 1968. 9. Leyden, J. J. More than skin deep. Emerg.Med. 14:126-141, Sept. 30, 1982. I0. Crissey, J. T. Scabies and pediculosis pubis. Urol.Clin.NorthAm. 11:171-176, Feb. 1984. 11. Estes, S. A. The Diagnosis and Management of Scabies. Piscataway, NJ, Reed & Carnrick, 1981. 12. Gurevitch, A. W. Scabies and lice. Pediatr.Clin.North Am. 32:987-1018, Aug. 1985. 13. Orkin, M., and Maibach, H. I. Current views of scabies and pediculosis pubis. Cutis (New York) 33:85-96, Jan. 1984. 14. Alexander, J.O.Scabiesinchildren.Clin.Pediatr. (Phil.) 8:73-85, Feb. 1969. 15. Espy, P. D., and Jolly, H. W. Norwegian scabies: occurrence in a patient undergoing immunosulrpression. Areh.Dermatol. 112:193-196, Feb. 1976. 16. Norins, A. L. Canine scabies in children. "'Puppie dog" dermatitis. Am.J.Dis.Child. !!7:239-242, Feb. 1969.
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