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Objectives: Increasing multidrug resistance amongst canine pathogenic staphylococci has renewed interest in topical antibacterial therapy for skin infections in the context of responsible veterinary prescribing. We therefore determined the activity in vitro of three clinically relevant topical agents and synergism between two of them against Staphylococcus pseudintermedius and Staphylococcus aureus. Methods: The MICs of fusidic acid (n=199), chlorhexidine (n=198), miconazole (n=198) and a 1:1 combination of miconazole/chlorhexidine (n=198) were determined for canine isolates [50 MRSA and 49 methicillin-resistant S. pseudintermedius (MRSP), 50 MSSA and 50 methicillin-susceptible S. pseudintermedius (MSSP)] collected from the UK and Germany using an agar dilution method (CLSI VET01-A4). Fractional inhibitory concentration (FIC) indices were calculated to assess the interaction of miconazole with chlorhexidine. Results: MICs of each drug/combination were significantly (P<0.0005) higher for S. aureus when compared with S. pseudintermedius. Most strains (n=172) had an MIC of fusidic acid of ≤0.03 mg/L (MIC ≥64 mg/L, n=5 MRSA). All strains had MICs of chlorhexidine of 0.5-4 mg/L, except for one MRSA (MIC=8 mg/L). All but four strains had MICs of miconazole of 1-4 mg/L (MIC=16 mg/L, n=3; MIC=256 mg/L, n=1). Miconazole/chlorhexidine (1:1 ratio) had a synergistic effect against 49/50 MRSA, 31/50 MSSA, 12/49 MRSP and 23/49 MSSP. Conclusions: Since the majority of these staphylococci, including methicillin-resistant isolates, had MICs that should be readily exceeded by topical skin application of these agents, their therapeutic efficacy for canine superficial pyoderma should be assessed. The synergistic interaction shown in vitro supports further clinical evaluation of miconazole/chlorhexidine combination therapy for staphylococcal infection. [ABSTRACT FROM AUTHOR]

Experiments at 20–97 GPa and 2000 K in the system CaO–MgO–TiO2–SiO2 constrain phase relations involving Mg-rich and Ca-rich perovskite solid solutions at conditions relevant to the Earth's deep Transition Zone and lower mantle. Bulk compositions were investigated with molar Ti/(Ti + Si) up to 0·5 within the quasi-ternary ‘perovskite plane’, which is defined by a reciprocal solution among the components MgSiO3, MgTiO3, CaSiO3, and CaTiO3. Multi-anvil experiments at 20 GPa and 2000 K on bulk compositions within the plane produce akimotoite coexisting with Ca-perovskites that lie close to the CaSiO3–CaTiO3 join. Higher-pressure experiments using a laser-heated diamond anvil cell constrain the position of a two-perovskite field that extends into the perovskite plane from the solvus along the MgSiO3–CaSiO3 binary join, where limited mutual solubility exists between MgSiO3 and CaSiO3 perovskites. On the join MgSiO3–MgTiO3, MgTiO3 solubility in MgSiO3 perovskite increases with pressure, with MgSi0·8Ti0·2O3 perovskite stable at ∼50 GPa. Limited reciprocal solution at ∼25 GPa results in an expansive two-perovskite field that occupies much of the Si-rich portion of the perovskite plane. Solution of Ti into Mg-rich and Ca-rich perovskites enhances the solubility of reciprocal Ca and Mg components, respectively. Increase in pressure promotes reciprocal solution, and the two-phase field collapses rapidly with pressure toward the MgSiO3–CaSiO3 join. We find that a single-phase, orthorhombic perovskite with near equimolar Ca and Mg is stable in a composition with Ti/(Ti + Si) of only 0·05 at 97 GPa, requiring that by this pressure the two-phase field occupies a small area close to the MgSiO3–CaSiO3 join. On the basis of experiments at∼1500 K, temperature has only a mild effect on the position of the Ca-rich limb of the solvus. Ca(Ti,Si)O3 mineral inclusions in deep sublithospheric diamonds could not have formed in equilibrium with Mg-perovskite owing to their virtual lack of MgSiO3 component at pressures of Mg-perovskite stability, but may have equilibrated with Transition Zone MgSiO3-rich phases at lower pressures; this observation can be extended generally to near-endmember CaSiO3 inclusions. On an iron-free basis, the average bulk compositions of clinopyroxene–ilmenite and orthopyroxene–ilmenite megacrysts from kimberlites plot in single-perovskite fields at pressures greater than about 45 and 65 GPa, respectively, when projected onto the perovskite plane. We predict that the effect of iron will not be large, and estimate that single-phase perovskites may form at somewhat lower pressures than in the iron-free system. Thus, the origin of pyroxene–ilmenite megacrysts from single-phase perovskite solutions in the lower mantle is plausible on the basis of phase relations, although a lower pressure magmatic origin appears more likely. Deeply subducted Ti-rich lithologies such as ocean-island basalt will crystallize a single perovskite rather than a two-perovskite assemblage beginning at pressures of ∼80 GPa. Normal mid-ocean ridge basalt and primitive mantle peridotite are expected to remain within a two-phase perovskite field until Mg-perovskite transforms to post-perovskite. [ABSTRACT FROM PUBLISHER]

Tenascin-X is a large extracellular matrix glycoprotein that is widely distributed within connective tissues and is associated with an autosomal recessive type of Ehlers-Danlos syndrome (EDS). Tenascin-X represents the first EDS susceptibility gene that does not code for a fibrillar collagen or collagen-processing enzyme. We describe a paediatric case of tenascin-X deficiency and review the literature. [ABSTRACT FROM AUTHOR]

Background. There is a lack of data regarding the use of narrowband ultraviolet B (NB-UVB) phototherapy in children with atopic dermatitis (AD). Many centres use this mode of treatment for children with AD; however, there have only been two previous studies observing the effect of NB-UVB in children with AD. Aim. We undertook a retrospective review of children with severe eczema who had undergone NB-UVB consecutively in our department between 1999 and 2005. Methods. All children with AD who had undergone NB-UVB consecutively in our department between 1999 and 2005 were identified from the phototherapy database. Their clinical notes were reviewed for information on age, sex, skin type, minimal erythema dose (MED), adjuvant therapy, previous therapy, adverse effects, number of exposures, cumulative dose, response to treatment and length of remission. Results. In total, 50 children (83%) completed more than 10 exposures of NB-UVB. Complete clearance or minimal residual activity was achieved in 20 children (40%). A good improvement was achieved in a further 10 children (23%), and a moderate improvement in 13 (26%). Children with MEDs > 390 mJ/cm2 were more likely to clear, and this was found to be statistically significant ( P = 0.02). Overall, the treatment was well tolerated and the median length of remission was 3 months. Conclusion. NB-UVB is an effective treatment for children with severe AD. Children with MEDs > 390 mJ/cm2 are more likely to clear. Further studies are needed to evaluate the efficacy of NB-UVB and long-term safety in treating children with severe AD. [ABSTRACT FROM AUTHOR]

Background It is generally accepted that the onset of sebum secretion occurs before puberty in boys and girls as a result of increasing androgen output during the adrenarche. Propionibacteria are part of the commensal skin flora and, in adults, are found in highest numbers in sebum-rich areas of skin such as the face and upper trunk. Previous studies investigating the association between sebum output and propionibacterial population densities have been cross-sectional and have been carried out mainly in adults. Objectives The purpose of this study was to examine the association between the onset of sebum secretion and expansion of the propionibacterial flora in a population of early adolescent children aged between 5.5 and 12 years, and to evaluate the temporal relation between the two factors longitudinally. In addition, the study aimed to evaluate the change with age in sebaceous gland activity and propionibacterial colonization on the skin and in the nares between children who developed acne and those who did not. Methods Biannual examinations of volunteers included age, pubertal (Tanner) stage, weight and height, lesion counting on the face, propionibacterial colonization on the skin surface and in the nares and sebum secretion. A longitudinal analysis based on all observations of each subject throughout the study was applied to examine the change of sebaceous gland activity and propionibacterial colonization with age and pubertal stage. A generalized estimating equation was used with a 0.05 level of significance. Results The commencement of sebum production was asynchronous, with only a small number of follicles initially starting to secrete sebum onto the skin surface. The number of secreting follicles and the area of sebum increased with age and pubertal stage (P < 0.0001, P < 0.05, respectively). Numbers of propionibacteria on the skin tended to increase after the age of 9 years, but not significantly so. In contrast, numbers of propionibacteria in the nares increased significantly with age (P < 0.0001) but not with pubertal maturation. Children who developed acne had higher sebum output and propionibacterial densities with increasing age than children who did not develop acne. This effect was significant for the increase of total sebum area with age in pubertal children (P = 0.0023), the increase in number of secreting follicles with age (P = 0.020) in prepubertal children, and the increase in propionibacteria densities in the nares with age (P = 0.0005) in pubertal children. Sebaceous gland activity and propionibacterial numbers on the skin surface remained unchanged with increasing age in children who did not develop acne. Propionibacterial population densities in the nares increased with age regardless of the development of acne. Conclusions Onset of sebum secretion and consequently expansion of the propionibacterial skin flora occur earlier in children who develop acne than in children of the same age and pubertal status who do not develop acne. These observations suggest that postponing the onset of sebum production or the expansion of the propionibacterial skin flora until after puberty may represent ways of preventing the disease or minimizing its severity. Determinants of propionibacterial colonization on the skin and in the nares may be different. [ABSTRACT FROM AUTHOR]

Background Allergic contact dermatitis (ACD) increases with age, and a prevalence of between 13·3% and 24·5% has been reported. Patch testing infants may be particularly difficult, and false-positive reactions may occur. Objectives The purpose of this retrospective study was to determine whether the site of primary dermatitis in children could predict a diagnosis of ACD. The current frequency of sensitization in children was also evaluated and the main sensitizing substances among children were verified. Methods Between 1995 and 2004, 500 children were patch tested and entered on to the patch test database at Leeds General Infirmary. Analysis of the database included identifying the presenting patterns of eczema and reviewing the patch test results for each child. Results Of the children, 133 (27%) had one or more positive patch test result. The effect of age on the likelihood of a positive patch test was highly significant ( P < 0·001). Girls were significantly more likely to have a positive patch test compared with boys: odds ratio for a positive test 0·62 (95% confidence interval 0·41–0·95; P = 0·029). Type IV allergy to nickel (33%) was the most frequent finding. Reactions to fragrance mix (18%), cobalt (11%), mercapto chemicals, Myroxylon pereirae and p-phenylenediamine (each 8%) were the next most common. No statistical significance was found in the relationship between the site of primary dermatosis and a positive patch test result. Conclusions The pattern of presenting dermatitis in children should not determine referral for patch testing. Any child with persistent eczema should be referred for patch testing. [ABSTRACT FROM AUTHOR]

Acne is usually recognized as a disorder of adolescence. However, the referral of patients over the age of 25 years with acne has significantly increased over the past 10 years. The clinical features of 200 patients over the age of 25 years, referred to our department for treatment of acne, were evaluated with a view to establishing possible aetiological factors. There were 152 (76%) women and 48 (24%) men. The mean age of the patients was 35.5 years (range 25-55 years). The acne was mild or moderate in severity, consisting principally of inflammatory lesions, with mean total acne grade (Leeds Grading Scale) of 1.125 for men and 0.75 for women. Most patients had persistent acne: but true late-onset acne (onset after the age of 25 years) was seen in 28 (18.4%) of women and four (8.3%) of men. Thirty-seven per cent of women had features of hyperandrogenicity. One hundred and sixty-four patients (82%) had failed to respond to multiple courses of antibiotics, and 64 (32%) had relapsed after treatment with one or more courses of isotretinoin. External factors, such as cosmetics, drugs and occupation, were not found to be significant aetiological factors. A family history revealed that 100 (50%) of patients had a first-degree relative with post-adolescent acne. Patients with post-adolescent acne appear to represent an increasingly important population of acne sufferers. External factors do not seem to have a significant aetiological role. Two main clinical groups were identified: those with persistent acne and those with late-onset acne. A minority of women also had features of hyperandrogenicity. These patients, and those with late-onset acne, may represent a subgroup who have underlying abnormalities of ovarian, adrenal or local androgen metabolism, and require separate investigation. [ABSTRACT FROM AUTHOR]

The article provides information on the case of a 32-month Pakistani girl diagnosed with Griscelli's syndrome characterized by partial albinism and immunodeficiency. The girl suffers from developmental delay, abdominal pain, and lethargy. She was also diagnosed with acute meningitis and hydrocephalus. The patient's histological examination shows that she has histiocytic tumour with a degree of erythrophagocytosis and lymphophagocytosis. Details about Griscelli's syndrome are also presented.

Trichoepitheliomas are benign epidermal appendage tumours that present most commonly as solitary lesions, and less often as multiple, symmetrically distributed lesions on the face, scalp, neck and trunk. Only a few patients have been reported in whom trichoepitheliomas were found as unusually configured linear or plaque-like confluent lesions, all of which occurred in patients with skin types V or VI. We describe a white girl with a hemifacial plaque of confluent naevoid trichoepitheliomas, the first report of such lesions in a white patient. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 19-month-old South Asian boy, who was diagnosed with juvenile xanthogranuloma (JXG). Topics mentioned include early diagnosis of exotropia and loss of vision, the further tests showing bilateral retinal detachment and the examination of several skin lesions. The article states the need to involve ophthalmology review as ocular JXG could include uveitis, hyphema and glaucoma.

The article presents a case of a 10-month-old girl with an asymptomatic purplish plaque on the right anterior chest, which had been present since birth. During the physical examination, a well-circumscribed nodule, composed of a dermal plaque with a superimposed cluster of firm yellow dermal nodules were found. Further, the histopathological findings of the disease, along with the diagnosis is also discussed.

The article presents a case involving a 13-year-old boy presented with a 3-month history of a slowly enlarging nontender xanthomatous-appearing nodule on his left elbow. He was diagnosed to have a primary tumoral calcinosis, characterized by large, calcified, painless masses, usually near joints, in otherwise healthy children and young adults. Histopathological findings and the discussion on the diagnosis are provided.

The article presents a letter to the editor on the treatment for recalcitrant hidradenitis suppurativa with oral ciclosporin.