Current antimicrobial susceptibility of cutaneous bacteria to first line antibiotics

Antimicrobial susceptibility of common bacterial species occurring on human skin appears to be falling. Data for the antimicrobial susceptibility of major groups of bacteria isolated from human skin during routine cultures were complied and analysed over a period of 9 months. Routine diagnostics of specimens from skin lesions and normal human skin were analysed for the presence of specified groups of bacteria. The species were identified using standard methods. Anti-microbial susceptibility was determined using a broth microdilution system giving breakpoints, the Sensititre system. Of the 333 Staphylococcus aureus, 129 Streptococcaceae, 180 Enterobacteriaceae and 120 Pseudomonadaceae strains investigated more than 5% of Staphylococcus aureus strains were resistant to flucloxacillin and thus methicillin (MRSA). More than 25% of Staphylococcus aureus strains were resistant to tetracycline and erythromycin. Many MRSA strains were found multi-resistant. Gentamicin was active against a large majority of Enterobacteriaceae strains but many Pseudomonadaceae strains were resistant. Compared with previous corresponding surveys methicillin-resistant Staphylococcus aureus strains are clearly on the increase. To prevent a further increase of resistant strains a defined strategy for antibiotic use is needed in dermatology.

The early phase of epidermal barrier regeneration is faster in patients with atopic eczema

BACKGROUND

Altered epidermal barrier function as determined by transepidermal water loss (TEWL) is a typical feature in patients with atopic eczema (AE).

OBJECTIVE

The purpose of this study was to assess the kinetics of epidermal regeneration after barrier perturbation induced by two different stimuli, namely acetone treatment (removal of stratum corneum lipids) and tape stripping (removal of the nonviable stratum corneum).

METHODS

Fifteen patients with AE and 12 nonatopic healthy controls were investigated. An area of 9.0 cm2 of clinically normal skin of the forearm flexural side was treated by acetone or tape stripping in a way that an increase in TEWL of 3.5-4.0 times the pretreatment value was achieved. TEWL was recorded directly after perturbation (tO), after 15 min (tl), 3 h (t2), 6 h (t3), 24 h (t4), 48 h (t5), 72 h (t6) and 96 h (t7).

RESULTS

The speed of epidermal regeneration was faster after acetone treatment, both in the patient and the control groups, with no significant difference between the two. However, after tape stripping at points t2, t5 and t6, TEWL values relative to tO were significantly lower in atopic skin as compared to normal skin (p < 0.05).

CONCLUSION

The faster regeneration of barrier function after tape stripping in patients with AE may be the result of a persisting mild disturbance of barrier function. It may be speculated that repair mechanisms are permanently activated, and therefore barrier recovery is faster. However, a complete restoration of the epidermal barrier function is not achieved, perhaps because of the decreased content of ceramides in atopic skin.

[Special characteristics of topical treatment in childhood]

Although the barrier function and thickness of the stratum corneum is fully developed in newborns, the infant shows numerous differences in cutaneous and systemic metabolism of topically applied substances in comparison to adults. This discrepancy between children and adults has been explained by the greater systemic availability due to the greater surface area to weight ratio in children. Several topically applied drugs such as hexachlorophene, phenol, salicylic acid and boric acid in high concentration or on large areas have caused toxic reactions and fatalities in infants. Therapeutic approaches to childhood dermatoses differ from these used in adults. These age-dependent differences concerning the topical application of glucocorticosteroids, urea and dyes are described for the treatment of atopic eczema. The development of innovative topical drugs may extend therapeutic options especially in children as shown by a new topical anesthetic cream improving the treatment of mollusca contagiosa, a common childhood problem. Finally, certain physiological differences should be considered in newborn and infant skin care.

Perioral dermatitis in children--clinical presentation, pathogenesis-related factors and response to topical metronidazole

BACKGROUND

Perioral dermatitis, a common skin disorder in young women, is rarely described in children.

OBJECTIVE

This study elaborates the clinical features of perioral dermatitis in children as well as possible pathogenetic mechanisms and the response to topical metronidazole.

METHODS

Seven children (4 females, 3 males between 4 and 12 years of age) were evaluated and dermatological examination was carried out. Pretreatment with topical corticosteroids was documented. Skin prick test with a panel of six common aeroallergens was performed in all children. All children were screened for gastrointestinal colonization with Candida albicans. Patients were treated with topical metronidazole 1% during the first 2 weeks. From the 3rd week on 2% metronidazole was used.

RESULTS

In all but one child topical corticosteroids had been used in the face prior to the first presentation at our outpatient department suggesting a possible pathogenetic role. An association with atopy or intestinal candida colonization was not found. In all children skin lesions resolved after 3-6 months. The children remained free of symptoms over an observation period of 2 years.

CONCLUSION

Perioral dermatitis has to be considered as differential diagnosis in children presenting with erythematous papules and papulovesicles in typical locations. Metronidazole proved to be effective and safe in the treatment of perioral dermatitis in children. Atopy and gastrointestinal colonization with C. albicans do not seem to play a role in the pathogenesis of perioral dermatitis.

Antimicrobial susceptibility testing of dermatophytes--comparison of the agar macrodilution and broth microdilution tests

Fifty dermatophyte strains, recently obtained from clinical material, belonging to 4 different species were examined for their susceptibility to 5 systemic or topical antimycotic agents using both an agar macrodilution and a broth microdilution test. Antimycotics compared were griseofulvin, itraconazole, sertaconazole, terbinafine and ciclopiroxolamine. A comparison of the minimum inhibitory concentrations (MIC) clearly showed differences between the two test methods applied. For all 5 antimycotics, MIC data were three- to seventy-fold lower in the microdilution test system. These differences, depending on the test method, have to be taken into account when comparing MIC data in the literature or when relating the in vitro data to the tissue concentrations determined in vivo.

Wood's light in Microsporum canis positive patients

In 64 patients with culturally proven Microsporum canis infections, Wood's light examination was performed. In 30 patients (47%) the characteristic fluorescence correlated with the cultural findings, whereas in the remaining 34 patients (53%), Microsporum canis was isolated, although Wood's light examination was negative. Of the 30 positive and 34 negative cases eight patients of each group had been pre-treated. From the results presented, Wood's light examination has a poor sensitivity in cases of Microsporum canis-infections.

Topical application of a platelet-activating factor (PAF) antagonist in atopic dermatitis

Platelet-activating factor (PAF acether) is a lipid mediator with a potent proinflammatory activity. Results derived both from in vitro and in vivo studies suggest a possible role of this substance in the pathophysiology of atopic dermatitis. A double-blind, randomized, multi-center, within-patient study was performed to evaluate the efficacy of a topically applied PAF antagonist (RO-24-0238) in 36 patients with atopic dermatitis. Over a period of 28 days, 0.25 ml of the PAF antagonist and the vehicle (placebo) were applied twice daily on opposite sites of symmetrical lesions (measuring 10 to 20 cm2 each). The overall assessment of the therapeutic efficacy did not demonstrate a superior effect of the PAF antagonist in comparison to placebo, and this was the same with the individual study parameters erythema, scaling, induration and exudation. For reducing pruritus, as assessed by the patient using a visual analogue scale, a statistically significant action was documented during the first 2 weeks of the study (p < 0.04; Wilcoxon rank sum test), with a continued, yet not statistically significant efficacy after weeks 3 and 4. The exact role of the pathological events of atopic dermatitis that might be influenced by a PAF antagonist remains to be determined, but the anti-pruritic component of this substance especially deserves further scientific interest.

Immunohistochemical investigations of genital ulcers caused by Haemophilus ducreyi

To gain information on the specific composition of the inflammatory infiltrate of genital ulcers caused by Haemophilus ducreyi, biopsies of 6 genital ulcers which were diagnosed as chancroid on clinical and microbiological grounds were subjected to immunohistochemical investigations after conventional haematoxylineosin staining. A variety of antibodies reactive against B- and T-cells, plasma cells and granulocytes were used with each tissue sections. The lymphocytic infiltrate of chancroid ulcers consisted of both B- and T-lymphocytes and showed a cluster-like formation. B-lymphocytes were preferentially localized perivascularly in the middle layer, T-lymphocytes mainly in the deep layer of the inflamed oedematous tissue. Results stress the importance of both B- and T-cell mediated immune responses in Haemophilus ducreyi infection.

[Allergy and atopic eczema: on the value of the "atopy patch test"]

The role of allergic reactions in eliciting and maintaining atopic eczema (AE) is still controversial. In a subgroup of patients with atopic eczema, exacerbations of itching and eczematous skin lesions have been described after contract with aeroallergens. To investigate this observation, an epicutaneous patch test with IgE-inducing allergens (atopy patch test, APT) has been proposed, which results in eczematous skin reactions in 30-70% of AE patients. Usage of allergen concentrations exceeding 5000 PNU/g in petrolatum allows testing on clinically uninvolved skin without potentially irritating epidermal tape stripping. The clinical relevance of positive APT reactions is suggested by comparison of APT with skin prick test, specific IgE, patient's history and eczema pattern. Patients with an eczema pattern with preferred localization of skin lesions in air-exposed areas, a predictive history and raised specific IgE (depending on allergen) were shown to have the highest rate of positive APT. Future controlled studies with allergen avoidance and reexposition may focus on this patient group.

Palpable migratory arciform erythema. Clinical morphology, histopathology, immunohistochemistry, and response to treatment

BACKGROUND

Palpable migratory arciform erythema is clinically characterized by sharply circumscribed, infiltrated erythematous patches that tend to spread irregularly, resulting in arciform morphologic features. The histopathologic features are characterized by a patchy inflammatory perivascular and periadnexal T-lymphocytic infiltrate throughout the dermis. The disease runs a chronic course and is rarely described in the literature.

OBSERVATION

Three middle-aged patients of both sexes had palpable migratory arciform erythema with 1, several, or multiple lesions on the trunk. There was a dense perivascular and periadnexal, predominantly lymphocytic infiltrate of the reticular dermis without any interstitial distribution of inflammatory cells. Absence of mucin deposits and plasma cells was a striking feature. The immunohistochemical profile showed an infiltrate dominated by T cells of polyclonal origin. In addition, polyclonal B cells and histiocytes were present in small numbers. In all 3 cases, oral antibacterial treatment resulted in a complete (2 patients) or temporary (1 patient) resolution of skin lesions.

CONCLUSIONS

Palpable migratory arciform erythema shows distinctive differences in clinical and pathological features and treatment in contrast to other diseases with cutaneous lymphocytic infiltrates, including lymphocytic infiltration of Jessner and Kanof. Therefore, it is likely a distinct disease entity.

[Treatment of atopic eczema in childhood]

Adjuvant basic therapy plays a central role in the therapeutic approach to atopic eczema in childhood. It involves the regular use of emollients and oil baths according to the clinical picture. Emollients containing urea may cause problems when used in younger children due to their stinging effect. Glucocorticosteroids still form the mainstay of anti-inflammatory therapy and are superior to other topical drugs with anti-inflammatory effects. Antihistamines preferably of the sedative type can be used successfully during periods of exacerbation. Systemic use of antibiotics is essential in cases of impetiginized atopic eczema. In cases of bacterial-triggered eczema, the topical use of antibiotics in cases of limited or antiseptics in generalized disease may be helpful.

[Perianal ergotismus gangraenosus]

Ergotamine-containing drugs are widely used in the treatment of acute migraine attacks. Among others, spastic vasoconstrictions are one of the possible side effects usually affecting the lower extremities and sometimes leading to gangrene. The case of a 75 year old woman is presented who was suffering from migraine-attacks since adolescence. Due to longterm use of ergotamine containing suppositories she developed perianal ulcers. After withdrawal of the drug the ulcers healed up entirely. The spectrum of ergotamine-induced side-effects and possible intervention strategies are discussed.

Effects of Pityrosporum ovale on proliferation, immunoglobulin (IgA, G, M) synthesis and cytokine (IL-2, IL-10, IFN gamma) production of peripheral blood mononuclear cells from patients with seborrhoeic dermatitis

The aetiology of seborrhoeic dermatitis (SD) is still unknown. An increased number of Pityrosposurm ovale in lesional skin of patients with SD has been suggested to play a crucial role in the pathogenesis of the disease since double-blind trials with antifungal drugs (e.g. ketoconazole) have shown that these agents result in a significantly reduced disease intensity. The frequent association of HIV infection and SD may be due to a suppressed cell-mediated immunity. In order to characterize the role of the humoral and cellular immune response in patients with SD the effects of a P. ovale extract on the proliferation of, and interleukin-2 (IL-2), IL-10 by an interferon-gamma (IFN gamma) production, and immunoglobulin (IgA, IgG, IgM) synthesis by peripheral blood mononuclear cells (PBMC) from patients with SD were studied in vitro. Healthy volunteers served as controls. PBMC from normal donors responded with a significantly increased proliferation to P. ovale antigen, whereas cells from patients with SD did not. Additionally, IL-2 and IFN gamma production by PBMC from patients with SD was markedly depressed compared with normal cells after stimulation with P. ovale. However, stimulation of PBMC from SD patients with P. ovale antigen induced significantly increased IL-10 synthesis. IgA, IgG and IgM synthesis was significantly increased in cultures of PBMC from patients with SD whether the cells were antigen-stimulated or not. Our results support the assumption that strong skin colonization with P. ovale in SD is due to an altered cellular immunity, which may be induced by increased IL-10 secretion.

[Treatment of atopic eczema in interdisciplinary cooperation between dermatology and psychosomatic medicine. An individual case report]

Atopic eczema is one of the most frequent dermatological diseases, with a still increasing incidence. Although its etiopathogenesis is still not completely understood, a variety of triggering factors are known. The following case report describes the clinical course of atopic dermatitis in a 2-year-old boy in whom both IgE-mediated allergic reactions and psychological factors were involved in triggering and maintenance of skin lesions. This demonstrates how important both dermatological therapy and close cooperation with the field of psychosomatic medicine can be.

[Induction of multiple melanocytic nevus cell nevi in 2 children with malignant hematologic systemic diseases and chemotherapy-induced immunosuppression]

Two children developed multiple melanocytic naevi after polychemotherapy administered for acute lymphoblastic leukaemia in one and for non-Hodgkin lymphoma in the other. Induction of naevi does not seem to be related to specific agents used in chemotherapy, but rather to the immunosuppression resulting from multiple-agent chemotherapy. There are reports in the literature of both intrinsically and iatrogenically immunosuppressed patients who have developed multiple melanocytic naevi.

Oral terbinafine in tinea capitis in children

Tinea capitis is a disease that frequently affects children. In most cases systemic antimycotic treatment is necessary Griseofulvin is still the drug of choice, but requires prolonged periods of treatment (several months). To estimate the efficiency and tolerability of terbinafine for treatment of tinea capitis in children, four patients (aged 3-9 years) with tinea capitis proven by culture were treated with terbinafine at a dose of 125 mg a day for different periods (4-10 weeks). Isolates were subjected to minimal inhibitory concentration testing against terbinafine and griseofulvin. In all four cases terbinafine treatment resulted in complete remission. The clinical response was accompanied by negative culture results on follow-up. Terbinafine was well tolerated in each case. Determination of the minimal inhibitory concentration confirmed the excellent in vitro activity of terbinafine against dermatophytes. Controlled studies involving a larger number of children are necessary to answer questions concerning dose and duration of terbinafine treatment as well as the frequency and severity of drug-related side-effects.