Pediatric Examination and Board Review (35 page)

(A) to have the family dog checked for fleas

(B) to unroof the blisters and apply antifungal cream

(C) that the child needs admission for IV antibiotics

(D) that the child will be admitted to the burn unit and child protective services will be called

(E) to burn the weeds in their garden

FIGURE 18-4.
See color plates.

ANSWERS

1.
(B)
Infants infested with the scabies mite often manifest a very extensive rash with involvement of the palms and soles. Burrows can often be found within the deep creases of these surfaces. The head can also be involved in the eruption, which is less common in older individuals, but a prominent facial rash is unusual. Annular lesions are more typical of a dermatophyte infection. Grouped vesicles on an erythematous base constitute the classic description of a herpetic lesion. Broken hairs in the scalp may suggest a tinea capitis infection.

2.
(A)
The most common cause of treatment failure of scabies infestations is inadequate treatment of contacts and the environment. All individuals sharing living quarters should be treated at the same time. Treatment involves application of 5% permethrin cream from the neck to the toes, including digit web spaces, gluteal cleft, genitalia, around and under nails. Cream should be left on overnight. Symptomatic individuals should repeat this treatment 1 week later. Simultaneously, the environment should be treated: all linens and clothing must be laundered in hot water and put through the dryer; items that cannot be laundered should be put in plastic for 1 week; floors, rugs, and furniture should be vacuumed. Permethrin-resistant scabies mites have not been reported.

3.
(C)
Appropriate use of 5% permethrin cream is a single application overnight, with repeat application in 1 week if the individual is symptomatic. This regimen applies to infants as well. The medication should be applied to the scalp of infants. Daily application is inappropriate and may lead to systemic absorption of the medication.

4.
(E)
Additional instructions for the environment are discussed in the answer to question 2. Professional extermination is not indicated. Items that cannot be laundered need to be sealed in plastic for 1 week. Application of mayonnaise to the hair is a treatment that has been recommended for head lice. There is no need to shave the head.

5.
(B)
Scrotal and penile nodules are strongly suggestive of a scabies infestation. Other itchy conditions, such as atopic dermatitis, rarely cause papules or nodules in this area. Conditions such as psoriasis and lichen planus can commonly affect the genitalia, but lesions are not typically nodular. Verrucous papules and nodules in the genital region may be a sign of sexual abuse.

6.
(E)
Head lice is common in school-age children and more common among members of races with straighter hair. They are relatively uncommon in those with coarse kinky hair. It is theorized that the organism cannot attach as easily to the oval hair shafts of kinky hair. Diffuse scaling in the setting of pustules and broken hairs is more suggestive of tinea capitis, and this infection is more common among African Americans. Round patches of frank alopecia are seen in alopecia areata, and this condition is not usually itchy. Diffuse greasy scale is typical of seborrheic dermatitis and more common in adolescents and adults. Decreased hair density with hairs of variable length are the findings of trichotillomania.

7.
(D)
Treatment failure of head lice is common. Pyrethrin-resistant organisms are becoming increasingly common. Additionally, suboptimal use of recommended treatments is common. The nonprescription cream rinse products are more effective when applied to dry hair and need to be left on the hair for several hours. Finally, removal of intact nits is critical because these represent the unhatched eggs. However, many of the apparent nits are typically empty and so there is a concern that “no nit” policies are overly conservative (see answer to number 8).

8.
(D)
The “no nit” policy is controversial. In some instances, old nits may simply represent the eggshell, without a live organism. Therefore, some patients with old nonviable nits will be barred from school, although they are in fact no longer infectious. It is thought that those nits closest to the scalp are most viable because of the necessary body temperature for hatching; however, this remains unproven and should not be relied on. Nits can be seen on hair shafts with the naked eye, but determination of the presence of an egg within requires microscopic examination.

9.
(E)
Body lice are rarely spotted on the skin itself but rather are visible to the naked eye within the seams of clothing. The skin lesions consist only of excoriations and areas of pinpoint bleeding representing sites of bites. Body lice most commonly affect the homeless and those with poor hygiene practices. Treatment consists mostly of removing infested articles of clothing and bedding. The perianal tape test is useful for documenting the presence of pinworms.

10.
(D)
Molluscum contagiosum is a poxvirus infection that is becoming increasingly prevalent among children. It is believed to be transmitted by skin-to-skin contact; however, it is unclear whether fomites are a risk and how much of a role is played by swimming and bathing with affected individuals. The lesions are classically found clustered in warm, moist areas such as the axillae, groin, antecubital fossae, and popliteal fossae. Patients may have few or dozens of lesions. Those with underlying skin disease such as atopic dermatitis have a higher risk of spreading the lesions because of a compromised skin barrier and baseline scratching.

11.
(A)
Watchful waiting is an acceptable treatment option in uncomplicated cases. The lesions do tend to spontaneously resolve eventually, although the time course is variable from weeks to months to years. Alternative treatments include curettage, cryotherapy, and application of cantharidin or a similar destructive agent. Salicylic acid is useful in the treatment of warts; however, it likely will not be effective for this condition and will be irritating. There is not a vaccine available.

12.
(B)
Verruca vulgaris refers to the common type of wart, caused by human papillomavirus. This infection is very common among children and adults. A large percentage of childhood cases actually resolve spontaneously over months to years. Lesions are distinguished by the rough surface that disrupts skin markings and the presence of thrombosed capillaries, which account for the friability and bleeding that are often reported. Callus will always be in an area of friction and pressure and will not disrupt the skin lines or produce thrombosed capillaries. Knuckle pads are an uncommon finding on the dorsal aspect of some patients’ interphalangeal and metacarpal phalangeal joints.

13.
(A)
Of the choices listed, cryotherapy is the best choice for wart therapy. Surgical excision will lead to scarring, and commonly the wart will grow back at the site because of incomplete removal. Electrocautery is also inappropriate. Curettage will not be effective for the relatively deep lesions. Vaccination is now available against human papillomavirus types 6, 11, 16, and 18. However common warts are generally caused by other serotypes and probably won’t be prevented by the current vaccines.

14.
(D)
Soft perianal papules in this setting are likely condylomas. Condylomas in any child should raise the concern for child abuse. However, there are many cases in which no risks for abuse are found and it is believed that autoinoculation of the virus by the patient is possible in this location. Additionally, children in diapers may be at risk of acquiring a papillomavirus from the hands of caregivers. Hemorrhoids are quite rare in childhood.

15.
(A)
Bullous arthropod bites can be very exuberant and frightening. They are often due to the bites of fleas, and only one member of the family may be affected. This individual is hypersensitive to the bite. The blisters arise on otherwise normalappearing skin, and a punctum may be visualized centrally. The lesions occur on exposed skin predominantly, such as the lower legs and arms. Children who play on the floor or ground are particularly susceptible. Management is supportive. Blisters may be drained, but the roof should be left intact as a natural dressing. Unusual blistering reactions in unusual locations should raise suspicion for abuse. Poison ivy reactions tend to cause more underlying dermatitis instead of the pristine blisters seen here. It is also not recommended to burn poison ivy because of the risk of aerosolizing the allergenic oils.

S
UGGESTED
R
EADING

Bodemer C. Human papillomavirus. In: Schachner LA, Hansen RC, eds.
Pediatric Dermatology.
3rd ed. Edinburgh, United Kingdom: Mosby; 2003:1087-1092.

Huynh TH, Norman RA. Scabies and pediculosis.
Dermatol Clin.
2004;22(1):7-11.

CASE 19: A 4-YEAR-OLD GIRL WITH AN ITCHY RASH

A 4-year-old girl presents to your office with her mother complaining of a long-standing itchy rash that has worsened in the last several days. The child’s mother states that the child has had rough skin since infancy and scratches persistently. She appears exhausted and exasperated. She describes the child digging at her skin and causing open sores and bleeding. In the past week, these symptoms have worsened, and the mother notes that whenever the weather changes the rash worsens.