Allen N. Sapadin

Interactions between calcipotriene and ultraviolet light

BACKGROUND Calcipotriene is often used with UVB or PUVA, but interactions between UV radiation and calcipotriene have not been examined extensively. OBJECTIVE Our purpose was to examine interactions between calcipotriene and UV light. METHODS Minimal erythema doses (MEDs) were determined with UVB and immediate pigment darkening was measured for UVA. The effect of calcipotriene ointment applied before phototesting was examined. Thick and thin applications of calcipotrience were compared. Calcipotriene ointment was applied to a small area on the skin before phototherapy. Patients received either UVB, PUVA, UVA, or no phototherapy. After phototherapy, the ointment was collected and assayed by reverse-phase, high-performance liquid chromatography. RESULTS MEDs for UVB and immediate pigment darkening for UVA were unaffected by calcipotriene. Thick application of calcipotriene, however, increased the MED, UVA caused substantial reductions in the concentration of detectable calcipotriene. CONCLUSION When used in conjunction with PUVA, calcipotriene should be applied after exposure to UVA.

Infliximab for the treatment of hidradenitis suppurativa

We describe a patient with hidradenitis suppurativa whose lesions responded to the administration of infliximab for suspected Crohns disease.

Pseudoxanthoma elasticum: An Update

Pseudoxanthoma elasticum (PXE) is an inherited disorder of elastic tissue with many systemic manifestations. The disease varies widely in its degree of expression and inheritance patterns and is believed to be considerably underdiagnosed due to lack of familiarity with the condition among physicians. The purpose of this article was to provide an update on important topics in PXE. Common presentations of the disease as well as the histopathology are discussed. The genetics of PXE as well as the importance of early diagnosis and genetic counseling are addressed. Special areas of concern, such as PXE in childhood, are reviewed. Finally, the article concludes with management of the disease and current areas of research.

Periumbilical pseudoxanthoma elasticum associated with chronic renal failure and angioid streaks—apparent regression with hemodialysis

Pseudoxanthoma elasticum (PXE) is a heritable connective tissue disease involving progressive fragmentation and dystrophic calcification of elastic fibers. Periumbilical disease as the exclusive site of cutaneous involvement is most commonly seen in the rare entity termed periumbilical perforating pseudoxanthoma elasticum (PPPXE). Patients with this disorder are generally obese, middle aged, multiparous black women with hypertension. The cutaneous lesions are well-demarcated, hyperpigmented, periumbilical plaques with keratotic papules on the periphery. Extracutaneous manifestations have rarely been described. We describe a patient with periumbilical PXE associated with chronic renal failure and bilateral angioid streaks. Histopathologic examination demonstrated typical calcification of elastic fibers with additional amorphous calcium deposits in the superficial dermis. Transepidermal elimination was not present. Normalization of the serum calcium-phosphate product resulted in regression of the lesions--both clinically and histopathologically. The relation between PPPXE and hereditary PXE is discussed. The role of chronic renal failure in precipitating PPPXE is considered.

Peeling agents and irritants, unlike tretinoin, do not stimulate collagen synthesis in the photoaged hairless mouse

Tretinoin has been shown to stimulate the synthesis of collagen in photoaged human and hairless mouse skin. It has been suggested that this partial reversal of photodamage by tretinoin is a consequence of low-grade inflammation. The purpose of this study was to compare the effect of tretinoin with a number of irritants and peeling agents on collagen synthesis. Hairless mice were irradiated thrice weekly for 10 weeks with UVB. In the 10-week postirradiation period, the mice were treated topically five times per week with tretinoin (0.05%), glycolic acid (10%), benzalkonium chloride (1.0%), sodium lauryl sulfate (5%), croton oil (5%) and the water—propylene glycol vehicle. Microscopic measurements showed that the tretinoin-induced zone of new collagen was twice the depth of that induced by irritants or vehicle. The salt-soluble collagen content was determined by HPLC analysis of hydroxyproline levels. Type III procollagen was quantified by radioimmunoassay. Tretinoin-treated skin had increased amounts of collagen and type III procollagen whereas irritant- and peeling agent-treated skins were similar to vehicle-treated controls. Immunofluorescence studies were confirmatory. These results demonstrate that these agents, unlike tretinoin, do not have the capacity to enhance collagen synthesis. Therefore, it is likely that the effect of tretinoin does not depend upon irritation.

Henoch–Schönlein purpura induced by clarithromycin

An 84‐year‐old Indian woman with no significant past medical history and no known drug allergies had been prescribed clarithromycin (250 mg twice daily) for pneumonia. The patient was receiving no other medications. Ten days after starting treatment, the patient developed a mild fever, eruption, and swelling of the ankles. Several days later, the patient developed a spreading, nonpainful, nonpruritic eruption, joint pain, gastrointestinal bleeding, and general malaise. Skin examination revealed numerous palpable purpuric macules and papules and petechiae on the lower extremities, mostly below the knees, and on the right hand. There were large blistering lesions around both ankles, some of which had ulcerated and had a necrotic center ( Fig. 1 ). Blood streaked stool was noted during rectal examination. Laboratory tests showed a normal white blood cell count, hematocrit, and hemoglobin. Serum urea nitrogen was 22 mg/dL (8–18 mg/dL) and creatinine was normal. Urinalysis revealed proteinuria of 0.9 g/24 h (<0.15 g/24 h) and a microscopic hematuria. Antistreptolysin O, antinuclear antibodies, cryoglobulins, and hepatitis serologies were all negative. Histology of the skin showed leukocytoclastic

Collagen loss in photoaged human skin is overestimated by histochemistry

It is well known that photoaged skin is characterized by increases in dermal matrix components that include glycosaminoglycans, proteoglycans and masses of abnormal elastic fibers accompanied by substantial collagen loss. Histochemical staining of such tissue gives the impression of “massive” loss of collagen and its replacement by these other matrix components. Early biochemical studies have lent support to this notion with a reported decrease in total collagen of ∼45% compared to protected skin. More recent studies report considerably less, but varying, amounts of collagen loss. Rarely have the two approaches, histochemistry and biochemical analysis, been used in the same study to examine the same tissue. In this study, collagen loss was quantified biochemically in paired biopsies from sun‐protected and sun‐exposed arm skin of moderately photoaged female subjects (age 51–77 years). The values obtained were compared with histochemical and immunochemical findings. Quantitatively, collagen loss on a per mg protein basis was small compared to the histochemical appearance.

Florid eruption of seborrheic keratoses associated with elevated insulin-like growth factor, hypoglycemia, and solitary fibrous tumor of the pleura

A 66‐year‐old man with a past medical history of hypertension and arthritis was hospitalized and treated for bacterial pneumonia. Chest X‐ray revealed a left‐sided chest mass. Computed tomography (CT) scan of the chest demonstrated a large heterogeneously enhancing mass occupying most of the left lower lobe and extending to the inferior aspect of the hilum. It measured 16.6 × 12 cm and caused a mild shift of the mediastinum to the right. The patient declined further work‐up or surgical resection of the mass. Dermatologic examination was unremarkable at that time.

Nail findings in pemphigus vulgaris

In the family described here, the brother and sister suffered from PV, but the mother and father were healthy. They were of Armenian origin. No Armenian family with PV has been reported previously. Another unusual feature was that the disease was localized to the face and scalp. The patients had no mucosal lesions or intact bullae. They were treated with low-dose corticosteroids and clinical improvement was seen after 1 month. Localized PV has rarely been reported in the literature. These unusual presentations may be explained by the regional variation in the expression of the pemphigus antigen. The lesions in our patients were localized on lightexposed body areas. Therefore, it can be suggested that PV may be triggered by ultraviolet irradiation in association with genetic factors. 6,7

Multiple subcutaneous angiolipomas associated with new-onset diabetes mellitus

A 44‐year‐old Hispanic man, with a past medical history of diabetes mellitus type 2 and cerebrovascular accident, presented to the Mount Sinai Department of Dermatology with sudden, fast‐growing nodules over both of his shins. Approximately 2 months before the appearance of the nodules, the patient was diagnosed with diabetes mellitus type 2 with hemoglobin A1c (HbA1c) of 8.5%. The patient was taking metformin orally, 500 mg three times daily, at the time of presentation. Six nodules appeared over a period of days. They caused a burning, throbbing pain upon ambulation. Over a period of 6 months, the lumps decreased in size, and two totally disappeared. The resolution of the nodules coincided with the control of the patients diabetes, as demonstrated by HbA1c of 5.5%. The patient denied trauma to the sites of the nodules. The patient denied any associated purpura or ecchymoses over the nodules. The past medical history was significant for a stroke with residual right hemiparesis at 42 years of age. The family history was negative for similar lesions, but an aunt did have diabetes mellitus type 2. The patient denied alcohol use, smoking, or intravenous drug use.