Milker's nodule: an occupational infection and threat to the immunocompromised.

Milker's nodule virus, also called paravaccinia virus, is a DNA virus of the parapoxvirus genus transmitted from infected cows to humans. It results from contact with cattle, cattle by-products or fomites. Classified as an occupational disorder, those at risk of exposure include farmers, butchers and agricultural tourists. The viral infection begins 5-15 days after inoculation as an erythematous-purple, round nodule with a clear depressed centre and a surrounding erythematous ring. While familiar to those in farming communities, the presence of the nodule may be concerning to others, particularly the immunosuppressed. Milker's nodules are self-limited in immunocompetent individuals and heal without scarring within 8 weeks. Another member of the Parapoxvirus genus, the orf virus, is also transmitted from animals to humans by direct contact. While complications are rare, haematopoietic stem cell transplant recipients are at risk of graft-versus-host disease, as the parapoxvirus may trigger these complications in immunocompromised individuals. In addition, paravaccinia may serve as the antigen source for the development of erythema multiforme. The unique structure and replication process of viruses in the Poxvirus family, while includes the Parapoxvirus genus, have been a focus for treatment of infections and cancer. Manipulation of these viruses has demonstrated promising therapeutic possibilities as vectors for vaccines and oncologic therapy.

Vitiligo: recent insights and new therapeutic approaches.

Vitiligo represents a selective destruction of the melanocytes. It is a relatively common, probably autoimmune disorder that affects people of all backgrounds and both genders. No particular group seems to be preferentially affected. Half of vitiligo patients have an onset before the age of 18 years. In regions where leprosy is endemic, individuals with vitiligo are often stigmatized due to similarities in appearance between the two diseases. We will review this important subject, emphasizing the latest therapeutic advances.

Pediculus humanus capitis: an update.

Head lice infestation, or pediculosis capitis, caused by Pediculus humanus capitis, is a common health concern. In the US, where pediculosis capitis is the most prevalent parasitic infestation of children, 6 to 12 million people are affected every year. Pediculosis capitis remains confined to the scalp. Scalp pruritus is the cardinal symptom, although patients with lice can be asymptomatic. Pruritus with impetiginization should prompt the physician to look for lice or viable nits. All close contacts should be examined. Treatment directed at killing the lice and the ova should be considered only if active lice or viable eggs are observed. The three fundamental effective treatment options for head lice are topical pediculicides, wet combing, and oral therapy. Spraying or fogging a home with insecticides or pediculicides is not recommended.

Alopecia areata. Pathogenesis, diagnosis, and therapy.

Alopecia areata is a common form of non-scarring alopecia that appears equally in males and females of any age, although children and adolescents are more commonly affected. The disorder is usually characterized by limited alopecic patches on the scalp, but more severe forms may affect the entire scalp (alopecia totalis) or body (alopecia universalis). Characteristic nail changes may also accompany hair loss. Alopecia areata has been linked with certain human leukocyte antigen (HLA) class II alleles, indicating a probable autoimmune etiology. Current research implicates T lymphocytes in the pathogenetic mechanism of disease. Other autoimmune diseases are also linked with alopecia areata. The diagnosis of alopecia areata is usually made clinically, although a biopsy is diagnostic for this condition. Treatment is challenging and aims at the regrowth of hair in affected individuals. Intralesional corticosteroid injections are widely used in mild disease. Topical anthralin and minoxidil may also be clinically efficacious. Topical sensitizers, such as squaric acid dibutlyester and diphenyl-cyclopropenone, are sometimes employed. Various therapies for the disease may have efficacy in different patients, making a universal treatment algorithm difficult to implement. Patients should be handled on an individual basis, with the final outcome based on the cosmetic regrowth of hair. Maintenance therapy is also important in patients that do achieve acceptable regrowth, necessitating a highly motivated patient and good rapport with the treating physician.

Usefulness of diagnostic criteria of tuberous sclerosis complex in pediatric patients.

The Tuberous Sclerosis Complex 1998 Consensus Conference clinical criteria represent an important advance in the diagnosis of tuberous sclerosis complex. Since many findings regarded as highly specific for tuberous sclerosis complex are not apparent until late childhood or adulthood, refinements by age may prove of value. We have stratified 106 children into five age groups (0 to 2 years of age, above 2 to 5 years, above 5 to 9 years, above 9 to 14 years, and above 14 to 18 years). Physicians should be alerted as to the frequency of the criteria in different stages of children.

Tinea capitis: current concepts.

Tinea capitis is an important fungal infection that may at times be a clinical, diagnostic and therapeutic challenge. It is common in childhood around the world, becoming almost epidemic in some communities. The central European and American experience with it is somewhat variable, due to different etiologic fungi. The use of topical antifungal agents and other approaches is stressed as of value alongside the use of systemic antifungal medication.

Acrodermatitis enteropathica-like eruption in an infant with nonketotic hyperglycinemia.

Acrodermatitis enteropathica is a rare inherited disorder characterized by zinc deficiency and a triad of dermatitis, diarrhea, and alopecia. It is an autosomal recessive condition thought to be due to the inability to absorb zinc from the gastrointestinal tract. Acquired zinc deficiency due to a variety of etiologies may produce a similar clinical picture. These causes include inadequate supply, malabsorption, and low zinc stores. In addition to zinc, deficiencies of other nutrients such as branched chain amino acids have induced an acrodermatitis enteropathica-like eruption. We describe a case of a 26-month-old boy with a rare inborn error of metabolism known as nonketotic hyperglycinemia who developed an acrodermatitis enteropathica-like eruption. In addition to zinc deficiency, the patient was deficient in branched chain amino acids due to a low protein diet instituted to reduce his elevated glycine levels. The rash did not respond to zinc replacement alone, and therefore is most likely a combination of amino acid and zinc deficiency. Acrodermatitis enteropathica-like eruptions have been described in other conditions that cause decreased serum amino acids, such as maple syrup urine disease and organic acidurias. This is the first case describing an association between acrodermatitis enteropathica and nonketotic hyperglycinemia.

Hair in infancy and childhood.

Of concern to new mothers is often the question, "Does my baby look normal?" In regard to the scalp and hair patterns of the infant, we have provided at least a basic guideline of what is generally considered the norm or variants of normal. Our goal was to outline accepted methods to care for an infant's hair and present certain problems a mother could encounter concerning the hair and scalp of her child or adolescent. We wish for this to serve as a practical guide to physicians in preparing mothers to care for their child's hair needs.

Eruptive syringomas.

We report the case of a seventeen-year-old woman with a rare presentation of a common appendageal tumor, the eruptive syringoma. We treated her with the retinoid isotretinate, which we had hoped would result in prevention or reduction of new tumors and disappearance of pre-existing lesions. The syringomas remained stable throughout our treatment effort and new lesions continued to appear.

Erythema toxicum neonatorum.

Erythema toxicum neonatorum is a common finding of unknown etiology affecting healthy newborn children, particularly those born at term. It is seen in the first days of life, but rarely at birth. Infants with it often have sterile papulopustules containing a predominance of eosinophils. It is important to distinguish from other cutaneous eruptions of neonates, some of which are serious.

Alopecia areata.

Alopecia areata is a frequent and physiologically compelling form of hair loss. It is most common in children and young adults, but can affect people of any age. Although it is usually limited to patches on the scalp, it may involve the entire scalp and other hair-bearing regions of the body. It may be associated with autoimmune disorders, especially of the thyroid. Its effective treatment often poses a difficult challenge.

Vitiligo.

Vitiligo is a common disorder afflicting people of all ages around the world. It produces milky white patches of depigmentation that cause significant morbidity due to cosmetic disfigurement. One should distinguish segmental from nonsegmental vitiligo, and be aware the latter is associated with an extremely small risk of associated autoimmune disorders. New therapeutic options offer some additional hope to patients with vitiligo, but more progress in the understanding of its pathogenesis and therapy is still needed.

Neonatal scabies.

A case of scabies infestation in a ten-week-old infant is described. Infestation in a neonate presents a clinical picture quite different from that found in older children and adults. Therapeutic options can be limited in infants. Current concepts and treatment modalities are discussed.

Childhood scleroderma and its peculiarities.

Based on a very large series of childhood scleroderma followed for more than ten years, the authors describe various subsets, which, in several aspects, differ significantly from the adult forms. Of special importance is a higher prevalence of linear scleroderma resulting in deformities and disabilities, as well as impairment of bone development in facial hemiatrophy. The immune abnormalities and vascular involvement leading to fibrosis are presented as the basic events in the pathogenesis. Critical discussion on a possible transitional form between localized and systemic disease and visceral involvement in cutaneous forms is followed by clinically applicable laboratory studies and management, including new therapeutic modalities.

Sign of Leser-Trélat with a metastatic mucinous adenocarcinoma.

We describe a middle-aged woman with the sudden onset of multiple seborrheic keratoses in association with a metastatic mucinous adenocarcinoma to the liver from an unknown primary neoplasm. This case illustrates the significance of the sign of Leser-Trélat and its association with cancer.

Lyme disease during pregnancy.

Lyme disease, caused by infection with Borrelia burgdorferi, can affect those exposed to a vector tick. Pregnant women are no exception, and such infection places the fetus at risk. It is particularly important to recognize the disease early so that effective therapy may be instituted. Although the present patient had a favorable outcome, not all do. Clinical diagnosis is especially important since conventional laboratory tests may be inadequate or require lengthy periods of time before a positive result occurs. The dermatologic sign of Lyme disease, erythema migrans, although occurring in only 50 percent of cases, is likely to be the most important diagnostic sign.

Subcutaneous symmetrical morphea with unusual onset as nodular vasculitis.

We present a case of widespread subcutaneous symmetrical morphea that started as nodular vasculitis. The characteristics histologic features were abundant inflammatory infiltrates in the subcutis, fascia, and muscle, with numerous macrophages and extensive vascular changes.

Klippel-Trenaunay-Weber syndrome.

The Klippel-Trenaunay-Weber syndrome is characterized by the triad of a port-wine stain, varicose veins, and bony and soft-tissue hypertrophy of an extremity. Recognition is usually possible during infancy or early childhood, and evaluation and treatment is important because morbidity may be minimized. We will review the clinical features, etiology, assessment, and treatment of patients with Klippel-Trenaunay-Weber syndrome.

Zinc deficiency in exclusively breast-fed infants.

Zinc deficiency in breast-fed infants is an important disorder. Unlike acrodermatitis enteropathica, it is transient and stops when nursing ends. We report two cases of premature infants, breast-fed only, who showed skin lesions resembling acrodermatitis enteropathica. Results of laboratory investigations revealed a lowered zinc level in the infants' serum and in the mothers' milk and a normal level of zinc in the mothers' serum. After the infants were given zinc supplements and their diets diversified, the skin lesions regressed and their serum zinc levels became normal.

Adult linear IgA bullous dermatosis: a polymorphic disorder.

We report on two patients with unusual forms of adult linear IgA bullous dermatosis. One was a middle-aged woman who had targetoid lesions and bullae on her trunk and extremities. This patient first presented with lesions that clinically resembled erythema multiforme, but these evolved into a widespread eruption with bulging, elongated bullae. Examination of a biopsy specimen showed changes compatible with dermatitis herpetiformis and bullous pemphigoid. Findings on immunofluorescence studies showed deposition of linear IgA at the basement membrane zone. The second patient was an elderly woman with intensely pruritic vesicles whom we classified as having vesicular pemphigoid, until the linear IgA band on direct immunofluorescent test results became the predominant immunofluorescent finding. These cases are reported because of their unusual clinical presentations. The mechanism for the targetoid lesions in the first patient is discussed.