A novel rat model for chemotherapy-induced alopecia.

BACKGROUND: More than half of all people diagnosed with cancer receive chemotherapy, and approximately 65% of these develop chemotherapy-induced alopecia (CIA), a side-effect that can have considerable negative psychological repercussions. Currently, there are very few animal models available to study the mechanism and prevention of CIA. AIM: To develop a clinically relevant adult rat model for CIA. METHODS: We first tested whether neonatal pigmented Long-Evans (LE) rats developed alopecia in response to the chemotherapeutic agents etoposide and cyclophosphamide. We then determined whether the rats developed CIA as adults. In the latter experiment, rat dorsal hair was clipped during the early telogen stage to synchronize the hair cycle, and starting 15 days later, the rats were treated with etoposide for 3 days. RESULTS: Neonatal LE pups developed CIA in response to etoposide and cyclophosphamide, similar to other murine models for CIA. Clipping of the hair shaft during early telogen resulted in synchronized anagen induction and subsequent alopecia after etoposide treatment in the clipped areas only. Hair follicles in the clipped areas had the typical chemotherapy-induced follicular dystrophy (dystrophic catagen). When the hair in the pigmented alopecic areas regrew, it had normal pigmentation. CONCLUSIONS: A novel, pigmented adult rat model has been established for CIA. By hair-shaft clipping during early telogen, synchronized anagen entry was induced, which resulted in alopecia in response to chemotherapy. This is the first clinically relevant adult rat model for CIA, and will be a useful tool to test agents for the prevention and treatment of CIA.

tert-butyl hydroperoxide, an organic peroxide, causes temporary delay in hair growth in a neonatal rat model.

tert-butyl hydroperoxide (tBHP), an organic peroxide, has been shown to cause irreversible damage to keratinocytes in vitro with prolonged administration at high concentrations, and reversible damage with short-term administration at low concentrations. To investigate the effects of tBHP on keratinocytes in vivo, we analysed hair growth in tBHP-treated neonatal rats. Sprague-Dawley and Long-Evans rat pups were injected subcutaneously with tBHP or vehicle once daily for 6 days, and hair growth was monitored. The tBHP-treated rats had a significant delay in hair growth. However, this delay reversed within days, and the hair coats, including hair pigmentation, of tBHP-treated and sham-treated rats were indistinguishable 2 weeks later. Histological analysis and BrdU labelling of S phase cells confirmed the delay in hair-follicle growth and its reversal in tBHP-treated rats. Our results indicated that the changes incurred in hair follicles by short-term use of high-dose oxidants in vivo are temporary and reversible.

Tissue-engineered skin in the healing of wound stumps from limb amputations secondary to purpura fulminans.

Currently wound treatment options of amputation stumps due to purpura fulminans include healing by secondary intention from wound debridement, split-thickness skin grafting, tissue and muscle flaps, plantar skin free transfer, skin expansion, artificial skin, and hyperbaric oxygen therapy. We saw a 6-month-old girl with purpura fulminans as a complication of meningococcemia. She developed necrosis of the distal extremities resulting in bilateral amputation of the lower limbs. Shortly thereafter the leg stumps also became necrosed and she underwent unsuccessful split-thickness grafts of lower limb ulcers. The patient's difficult-to-heal wounds made her an excellent candidate for treatment with tissue-engineered skin. At 10 months of age, this was applied to her previously nonhealing wounds. The tissue-engineered skin induced rapid healing of the patient's chronic amputation stump ulcers and provided her with substantial pain relief. In conclusion, tissue-engineered skin appears to be a potential beneficial treatment for chronic wounds in children with nonhealing amputation stumps.

Localized scleroderma or morphea?

Morphea is a frequently mild, benign, and self-limiting skin disease with a less than 1% reported chance of progressing to systemic scleroderma. Morphea is a sufficient and less terrifying name for these disorders than localized scleroderma.

Tissue-engineered skin (Apligraf) in the healing of patients with epidermolysis bullosa wounds.

BACKGROUND: At present, wound treatment of inherited epidermolysis bullosa (EB) is only supportive. OBJECTIVE: To determine the safety and clinical effects of tissue-engineered skin (Apligraf; Organogenesis Inc, Canton, Mass) in the healing of wounds of patients with different types of EB. DESIGN: An open-label uncontrolled study of 15 patients with EB treated with tissue-engineered skin. Each patient received tissue-engineered skin on up to 2 wounds on each of 3 clinic visits: day 1, week 6, and week 12. They were evaluated 7 (+/- 3) days and 6 weeks after each round of treatment. A quality-of-life survey was administered during week 6. SETTING: University of Miami, Miami, Fla. PATIENTS: Volunteers with EB. MAIN OUTCOME MEASURE: Safety and wound healing. RESULTS: A total of 69 different acute wounds received tissue-engineered skin at the day-1 (24 wounds), week-6 (23 wounds), and week-12 (22 wounds) visits. Overall, 63 wounds (79%) were found healed at the day-7 visit. Of the acute wounds, 82% (51/62) were healed 6 weeks after being treated, 75% (27/36) after 12 weeks, and 79% (11/14) after 18 weeks. Nine chronic wounds were also treated. Four were healed at 6 weeks; however, 7 were still open at the last clinic visit (week 18). There were no signs of rejection or clinical infection and no adverse events related to the tissue-engineered skin. The quality of life for most patients improved after treatment. Compared with patients' recollection of wounds treated with standard dressings, healing was faster and less painful. CONCLUSION: In this series of patients, tissue-engineered skin induced very rapid healing, was not clinically rejected, and was devoid of adverse effects. It was felt by the patients and families to be more effective than conventional dressings for EB wounds.

The use of tissue-engineered skin (Apligraf) to treat a newborn with epidermolysis bullosa.

BACKGROUND: Inherited epidermolysis bullosa (EB) is a mechanobullous disorder. The Dowling-Meara variant, a subtype of EB, is characterized by widespread blister formation that may include the oral cavity and nails. Many patients with the Dowling-Meara phenotype are at increased risk of sepsis and death during infancy. The treatment of EB is generally supportive. The tissue-engineered skin used (Apligraf) is a bilayered human skin equivalent developed from foreskin. It is the only Food and Drug Administration-approved skin equivalent of its kind. It is approved for the treatment of venous ulcers of the lower extremities. It has also been used to treat acute wounds, such as graft donor sites and cancer excision sites. OBSERVATION: To our knowledge, we describe the first case in which a newborn with EB, Dowling-Meara variant, was treated with bilayered tissue-engineered skin. The areas treated with the tissue-engineered skin healed faster than the areas treated with conventional therapy. Most of the areas treated with tissue-engineered skin have remained healed, without developing new blisters. These areas appear to be more resistant to trauma. CONCLUSIONS: Our early success with tissue-engineered skin in this patient may have a significant impact on the future treatment of neonates with EB simplex. Future studies are needed to determine if the beneficial effects of tissue-engineered skin are reproducible in other neonates with EB simplex and in patients of all ages with different subtypes of EB.

Pagetoid self-healing Langerhans cell histiocytosis in an infant.

We report Langerhans cell (LC) histiocytosis in a male infant who developed numerous papular lesions on the trunk and posterior scalp soon after birth and spontaneously recovered from the disease within 7 months. Histologically S-100-positive cells were detected in the epidermis and papillary dermis, in some lesions mostly in the epidermis. Tumor cells in the epidermis were either clustered, forming nests, or scattered singly in pagetoid fashion. Electron microscopy confirmed the presence of Birbeck granules in these cells. They exhibited many interesting features usually not found in normal LCs, including mitosis, frequent apoptosis, Birbeck granules invaginated in the nucleus, autophagocytosis of Birbeck granules, and active ingestion of extracellular material through Birbeck granules attached to cell membranes. It is suggested that either a strong epidermotropism of tumor cells or a proliferation of the resident LCs of the epidermis is responsible for this intraepidermal growth pattern. Cellular necrosis through very active apoptosis and the superficial nature of the growth might have contributed to the self-healing course in this patient.

IgA antibodies in chronic bullous disease of childhood react with 97 kDa basement membrane zone protein.

Chronic bullous disease of childhood (CBDC) is an autoimmune blistering disease occurring in prepubertal children. Both CBDC and its adult counter-part, linear IgA bullous dermatosis (LABD), are characterized by linear deposition of IgA along the cutaneous basement membrane zone (BMZ). Circulating IgA antibody in LABD has been found to bind to a 97-kDa BMZ antigen, whereas the antigen in CBDC has not been well characterized. The purpose of this study was to evaluate the immunoreactivity of BMZ IgA antibodies in a series of CBDC patients. We evaluated 12 sera from patients with CBDC with circulating IgA anti-BMZ antibodies on indirect immunofluorescence (IIF), which stained the epidermal side of split skin with titers ranging from 1:20 to 1:640. Immunoblotting was performed against two preparations of BMZ proteins: one enriched with the two bullous pemphigoid antigens (BP230, BP180) and one enriched with the LABD antigen (LABD97). Eight of the twelve sera reacted with a 97-kDa protein that co-migrated with the protein detected in many LABD sera. The intensity of the reaction on immunoblot correlated with serum antibody titers. There was no consistent pattern of reactivity of the IgA anti-BMZ antibodies with either the BP230 or BP180 antigens, although two sera reacted with several higher molecular mass proteins (160-200 kDa). The significance of this reactivity was examined with immunoblotting using BMZ-affinity-purified antibodies, and ELF using nitrocellulose-eluted antibodies. One serum also contained anti-BMZ IgA antibodies that reacted with a 180-kDa protein, corresponding to BP180. We conclude that IgA antibodies in CBDC sera recognize a 97-kDa BMZ antigen present on the epidermal side of BMZ split skin that co-migrates with the antigen previously identified in LABD. These findings suggest that CBDC and LABD are the immunologically related disorders occurring in different age groups.

Dermatologic consultations in the hospital setting.

BACKGROUND AND DESIGN: Dermatologic practice occurs mainly in the outpatient setting. The reasons for, frequency, and impact of inpatient dermatologic consultation are largely unstudied. In this report, we prospectively studied dermatologic consultation in the major teaching hospital complex of a medical school. Over a period of 8 months, we prospectively recorded the demographics of the patients for whom consultation was requested, the provisional dermatologic diagnosis of the referring service, the final diagnosis of the dermatologic service, and the tests necessary to arrive at a final diagnosis. RESULTS: During a period of slightly over 8 months, dermatologic consultation was requested and delivered to 591 patients who were either hospitalized or being evaluated in the emergency department or other urgent care settings. The services requesting consultation most frequently were medicine (39%), pediatrics (14%), surgery (12%), psychiatry (6%), and neurology (3%). In 51% of consultations, the patients were younger than 45 years of age. Diagnostic tests, including Tzanck smear and potassium hydroxide preparation, confirmed the clinical diagnosis in up to 50% of cases. Dermatologic consultation changed dermatologic diagnosis and treatment in more than 60% of the patients. Generally, the dermatologic diagnoses most frequently missed by the referring service were common conditions with established treatment. CONCLUSIONS: Dermatologic consultation in the hospital setting improves dermatologic diagnosis and has an impact on treatment.

Eosinophilic pustular folliculitis in infancy and childhood.

We describe nine patients with eosinophilic pustular folliculitis occurring in infancy. All patients had recurrent crops of pruritic papules primarily affecting the scalp and brow region of the face. Biopsy specimens revealed folliculitis with a predominant eosinophilic infiltrate. Bacterial and fungal cultures of pustules were negative. Most patients had leukocytosis and eosinophilia. Clinical response to topical corticosteroid and/or systemic antibiotic therapy was noted. Eosinophilic pustular folliculitis of infancy must be considered in the differential diagnosis of pustular disorders in infancy.

Sézary syndrome in an 11-year-old girl.

All forms of cutaneous T-cell lymphoma are rare in children. We describe an 11-year-old girl who had generalized exfoliative erythroderma, intense pruritus, peripheral lymphadenopathy, mycosis cells in the skin and lymph nodes, and Sézary cells in the peripheral blood. Results of a biopsy specimen of involved skin showed changes consistent with mycosis fungoides. A classic case of Sézary syndrome has not previously been reported in childhood or preadolescence.