Jonathan K. Wilkin

Prostaglandins and nicotinate-provoked increase in cutaneous blood flow.

The mechanism of topically applied methyl nicotinate–induced local cutaneous erythema was studied in normal human subjects. Aqueous methyl nicotinate (0, 0.1, 1.0, 10.0, and 100 mmol/L) was applied to the volar forearms in quadruplicate after oral pretreatments with 25 mg doxepin hydrochloride, 600 mg ibuprofen, 50 mg indomethacin, 975 mg aspirin, and lactose placebo. The cutaneous vascular response was monitored by laser Doppler velocimetry. Although doxepin did not affect the cutaneous vascular response to methyl nicotinate, indomethacin, ibuprofen, and aspirin significantly suppressed the response. Because indomethacin, ibuprofen, and aspirin have different chemical structures, the common property of inhibition of the response to methyl nicotinate may be assigned to their common pharmacologic action, i.e., inhibition of prostaglandin bioformation.

Aspirin blocks nicotinic acid-induced flushing.

Nicotinic acid flushing after placebo and 975‐mg oral doses of aspirin was assessed in 29 normal subjects over a range of nicotinic acid doses. Intensity of flushing was assessed by the change in malar thermal circulation index (ΔMTCI). Aspirin pretreatment resulted in smaller ΔMTCIs at the higher doses of nicotinic acid. At the lower doses the change in the index after pretreatments with both aspirin and placebo remained low, suggesting that very little flushing was provoked by these doses. These results are compatible with the proposed mediation by prostaglandins of the nicotinic acid–induced flush. According to the ΔMTCI method, flushing is quantitatively characterized as a nonquantal, dose‐response reaction of variable intensity.

Unilateral dermatomal superficial telangiectasia. Nine new cases and a review of unilateral dermatomal superficial telangiectasia.

Unilateral dermatomal superficial telangiectasia (UDST) may be congenital or acquired. Acquired UDST may occur coincident with physiologic states of estrogen increase, including puberty and pregnancy in women and adrenarche in men. Acquired UDST may also occur in estrogenized pathologic states such as chronic hepatic disease in alcoholism. The occurrence during estrogenized states, the dermatomes of distribution, and the presence of anemic halos suggest kinship with arterial spiders. UDST and some cases of benign, generalized telangiectasia may be local and universal forms, respectively, of the same pathologic process in the cutaneous microvasculature. Further, this is compatible with both the concept that UDST results from a somatic mutation and the usual nonfamilial presentation of UDST.

Effect of nadolol on flushing reactions in rosacea

The effect of nadolol versus placebo on both flushing provoked in a laboratory setting and spontaneous flushing was studied in 15 patients with erythematous telangiectatic rosacea. The intensity of the flushing reactions was assessed in the laboratory by the cutaneous perfusion index method with laser-Doppler velocimetry. No effect of nadolol on the flushing reactions provoked in the laboratory was detected.

Vascular abnormalities in lichen aureus

Lichen aureus is an infrequently reported subset of the pigmented purpuric dermatoses. A review of the English literature suggests the golden to purple colored lesions are asymptomatic or mildly pruritic with no regression once established. A case report of a 56-year-old man with lichen aureus of the thighs is presented. This case is unusual in that the patient had persistent pain at the lesion site. Furthermore, increased capillary fragility and koebnerization were both demonstrated. Treatment of an asymptomatic urinary tract infection resulted in temporary subjective and objective improvement.

Unilateral nevoid telangiectasia: three new cases and the role of estrogen.

Over a period of one month three patients attending a womens outpatient clinic at a general hospital were observed to have unilateral telangiectatic lesions. To our knowledge, only 12 cases of unilateral nevoid telangiectasia have been previously reported; this report would bring to 15 the number of cases of this syndrome. The temportal aspect of the onset of the lesions among these patients strongly supports the role of estrogen in the appearance of unilateral nevoid telangiectasia.

Red lunulae revisited: A clinical and histopathologic examination

Red lunulae are associated with rheumatoid arthritis, systemic lupus erythematosus, alopecia areata, cardiac failure, hepatic cirrhosis, lymphogranuloma venereum, psoriasis, carbon monoxide poisoning, twenty-nail dystrophy, and reticulosarcoma. We examined four patients with red lunulae. Three had chronic obstructive pulmonary disease. Two of these three were alcohol abusers and were without any of the conditions previously associated with red lunulae. Two of the four also had palmar erythema. Histopathologic examination of the red lunula in one of the four cases did not show signs of neovascularization. We report our findings in these patients, which suggest that red lunulae result from increased arteriolar blood flow, a vasodilatory capacitance phenomenon, or changes in the optical properties of the overlying nail so that normal blood vessels become more apparent.

Squaric acid and esters: Analysis for contaminants and stability in solvents

Two squaric acid diesters, squaric acid diethyl ester (SADEE) and squaric acid dibutyl ester (SADBE), have been suggested as replacements for 2,4-dinitrochlorobenzene in the treatment of alopecia areata and alopecia totalis. We synthesized these squaric acid diesters and examined them for the presence of carcinogenic contaminants, hexachlorobutadiene and tetrachloro-2-cyclobutene-1-one, by gas chromatography-mass spectrometry (GC-MS). The stability of SADBE to hydrolysis by water in acetone, butanol, isopropanol, and absorbent ointment with and without molecular sieves was examined. The stability of SADEE in ethanol and acetone, with and without molecular sieves, was also studied. Hydrolysis products were detected by their formation of a colored complex with ferric chloride. This complex absorbs in the visual range at 480 nm, thus affording a convenient method for determination of the concentration of free squaric acid in a solution. No contaminants were found by positive or negative ion detection in our GC-MS system. At the end of 3 weeks the extent of hydrolysis was greater in alcohols than in acetone when 10 and 100 molar excess of water were added to the solutions. In the presence of molecular sieves, hydrolysis was reduced even at 100 molar excess of added water in alcohol ar acetone. However, under storage conditions without sieves, acetone solutions and alcohol solutions were equally stable over a period of 2 months. Molecular sieves reduce hydrolysis of squarate esters in the presence of a large molar excess of water, regardless of solvent.

Acne severity grading: Determining essential clinical components and features using a Delphi consensus

BACKGROUND There are multiple global scales for acne severity grading but no singular standard. OBJECTIVE Our objective was to determine the essential clinical components (content items) and features (property-related items) for an acne global grading scale for use in research and clinical practice using an iterative method, the Delphi process. METHODS Ten acne experts were invited to participate in a Web-based Delphi survey comprising 3 iterative rounds of questions. RESULTS In round 1, the experts identified the following clinical components (primary acne lesions, number of lesions, extent, regional involvement, secondary lesions, and patient experiences) and features (clinimetric properties, ease of use, categorization of severity based on photographs or text, and acceptance by all stakeholders). In round 2, consensus for inclusion in the scale was established for primary lesions, number, sites, and extent; as well as clinimetric properties and ease of use. In round 3, consensus for inclusion was further established for categorization and acceptance. Patient experiences were excluded and no consensus was achieved for secondary lesions. LIMITATIONS The Delphi panel consisted solely of the United States (U.S.)-based acne experts. CONCLUSION Using an established method for achieving consensus, experts in acne vulgaris concluded that an ideal acne global grading scale would comprise the essential clinical components of primary acne lesions, their quantity, extent, and facial and extrafacial sites of involvement; with features of clinimetric properties, categorization, efficiency, and acceptance.

An unusual case of calcinosis cutis

A case of calcinosis cutis is presented in a patient with hypercalcemia of unknown etiology. The axillae and inguinal areas were involved and the clinical and histologic picture is compared with pseudoxanthoma elasticum. We propose that the similarities between the two diseases stem from a common origin in damaged elastic fibers.