The WHO ICD-11 Classification of Dermatological Disorders: a new comprehensive online skin disease taxonomy designed by and for dermatologists

In May 2019, the World Health Assembly officially adopted the Eleventh Revision of the International Classification of Diseases (ICD-11)¹ . When the current 10th Revision (ICD-10) was released some three decades ago, the world was at the beginning of the modern information technology era. The World Health Organization (WHO) had long recognised that the "one size fits all" nature of ICD-10 and its inability to adapt to change seriously hampered its usefulness in healthcare research and management. The initial designs for ICD-11 were formulated by the WHO in 2007. Since then, many individuals from around the globe have participated in its development.

Consensus statement on the management of chronic hand eczema

The management of chronic hand eczema is often inadequate. There are currently no evidence-based guidelines specifically for the management of chronic hand eczema, and evidence for established treatments for hand eczema is not of sufficient quality to guide clinical practice. This consensus statement, based on a review of published data and clinical practice in both primary and secondary care, is intended to guide the management of chronic hand eczema. It describes the epidemiology and pathogenesis of hand eczema, its diagnosis and its effect on patients' quality of life. Management strategies include a skin education programme, lifestyle changes, and the use of emollients, barriers and soap substitutes. Topical drug therapy includes topical steroids and calcineurin inhibitors. Treatment with psoralen ultraviolet A and systemic therapies may then be appropriate, although there is no strong evidence of efficacy. Alitretinoin has been shown to be effective in a randomized controlled trial, and is currently the only treatment specifically licensed for the treatment of hand eczema. Recommendations for management are summarized in a treatment algorithm.

Atopic dermatitis and allergic reactions to individual fragrance chemicals

BACKGROUND

Allergic contact dermatitis prevalence is reported as equal in atopic and nonatopic dermatitis. Atopic dermatitis is under-represented in those with allergic contact dermatitis to agents having cutaneous and dietary exposure. We compared rates of atopic dermatitis between patients with allergic contact dermatitis arising out of individual fragrance chemicals with known oral/cutaneous exposure against exclusively cutaneous exposure.

METHODS

Between 1982 and 2007, 37 065 dermatitis patients were tested with Fragrance mix I. Those who were positive were tested for individual fragrance allergy. Chemicals were categorized according to whether their exposure pattern was solely cutaneous, oral or mixed. Current and past atopic dermatitis rates were compared between the whole population and groups allergic to individual fragrances. Age and gender were controlled.

RESULTS

Cinnamic alcohol and cinnamal allergy groups had reduced rates of both 'current' [24/266 (9.0%) P = 0.0008, 38/364 (10.4%) P = 0.0005] and 'past' atopic dermatitis [44/266 (16.5%) P = 0.009, 70/346 (19.2%) P = 0.037]. Atopic dermatitis rates in groups allergic to Evernia prunastri and hydroxycitronellal (cutaneous exposure only) were not reduced [120/597 (20.1%) and 41/153 (26.8%)]. Groups allergic to cinnamic alcohol (P < 0.0001, P < 0.0001) and cinnamal (P < 0.0001, P < 0.004) had reductions in 'current' and 'past' atopic dermatitis, compared with Evernia prunastri.

CONCLUSIONS

Patients allergic to individual fragrances with dietary exposure have reduced rates of atopic dermatitis. This suggests that patients with atopic dermatitis have heightened oral tolerance to dietary haptens, in contrast to the known close association of atopic dermatitis with food-protein allergy. Haptens may interfere with food protein tolerance by binding to soluble protein to alter its configuration and immunogenic profile.

Does hapten exposure predispose to atopic disease? The hapten-atopy hypothesis

Contact allergy data indicates that atopics have heightened oral tolerance to haptens (chemical allergens). We speculate here, that artificially increased oral exposure to chemicals compete with dietary proteins for the development of oral tolerance, predisposing to the acquisition of food protein allergy and representing one driver for the increasing prevalence of protein allergy and/or atopy. Hapten exposure via other surfaces such as the skin and airways might also be important in promoting atopic disease. Consistent with this hypothesis it is notable that over 40 years, with the huge increase in atopic disease, there has also been an increase in dietary hapten exposure through processed food, formula milk and oral antibiotic and drug use.

DRESS syndrome caused by efalizumab

We report a case of drug reaction with eosinophilia and systemic symptoms (DRESS) to efalizumab. A 52-year-old man developed a widespread papulovesicular rash after 4 weeks of treatment with efalizumab (1.0 mg/kg/week) for treatment-resistant severe psoriasis. Histology revealed a subepidermal blister with eosinophil-rich inflammatory cell infiltrate. Subsequently, the patient developed high peripheral eosinophilia, abnormal liver function, malaise and fever, all requiring inpatient admission. Efalizumab was discontinued immediately, but the rash persisted for 4 months and was only controlled by oral prednisolone at a dose of 30 mg/day. To our knowledge, this is the first reported case of DRESS caused by efalizumab.

Frequency of allergic contact dermatitis to isoeugenol is increasing: a review of 3636 patients tested from 2001 to 2005

BACKGROUND

Isoeugenol is an important fragrance allergen. The cosmetic industry was recommended voluntarily to reduce concentrations of isoeugenol in finished cosmetic products from 0.2% to 0.02% in 1998. It was suspected that this would reduce the incidence of patch test positivity in individuals undergoing routine patch testing after approximately 2-3 years (the Dillarstone effect).

OBJECTIVES

To review our patch test data since the change in practice by industry, to see if there has been an observable decrease in isoeugenol contact sensitivity.

METHODS

We retrospectively analysed all subjects patch tested to isoeugenol 1% pet. in the St John's Department of Cutaneous Allergy over a period of 5 years, commencing 3 years after the changes.

RESULTS

We identified 3636 subjects, 97 of whom were positive for isoeugenol. Year-on-year incidence shows an increasing trend, with an overall incidence of 2.67%. Using the exact Cochran-Armitage test, this ascending trend is statistically significant (P = 0.0182). Seventy-two of 97 isoeugenol-positive subjects were also positive to fragrance mix I. Other fragrances positive in these 97 patients included Myroxylon pereirae (30%), Evernia prunastri (22%) and eugenol (15%).

CONCLUSIONS

We suspect that the increasing trend may be due to allergen substitution with compounds chemically related to isoeugenol, or which hydrolyse to isoeugenol itself.

Screening for asymptomatic carriage of Trichophyton tonsurans in household contacts of patients with tinea capitis: results of 209 patients from South London

BACKGROUND

There is currently an epidemic of tinea capitis in urban areas of developed countries caused by Trichophyton tonsurans. Recurrence or re-infection with dermatophyte is not uncommon after adequate oral treatment. Asymptomatic carriers who are household contacts may partly explain this observation by forming a reservoir for infection.

PATIENTS/METHODS

Two-hundred and nine household contacts of patients with tinea capitis were examined and screened for asymptomatic carriage of dermatophyte.

RESULTS

Only 7.2% had clinically evident disease yet 44.5% had silent fungal carriage on the scalp. Children under 16 years were much more likely to be carriers than adults (P < 0.001) and males were less likely than females to be affected (P < 0.01).

CONCLUSION

This evidence poses questions about factors relevant in transmission of dermatophytes. The authors propose that all household contacts of patients with tinea capitis should be offered screening to eradicate a potential reservoir of infection.

Sclerodermatous graft-versus-host disease: clinical spectrum and therapeutic challenges

Sclerodermatous graft-versus-host disease (GVHD) is a rare complication of bone marrow transplantation. While GVHD is often associated with the beneficial graft vs. tumour effect, it also contributes towards significant morbidity and mortality. No reliably effective treatment has yet been established. We present 10 patients with haematological malignancies who underwent an allogeneic stem cell transplant and developed sclerodermatous GVHD. Donor lymphocyte infusion administered for relapse or reducing donor T-cell chimerism was a known trigger for sclerodermatous GVHD in four of the patients. Treatment with immunosuppressants, psoralen plus ultraviolet A (PUVA) and extracorporeal photopheresis has been largely unsuccessful in their management. Intensive immunosuppression including the use of anti-CD20 monoclonal antibody may have contributed to relapse of leukaemia in one patient 10 years after her transplant. Sclerodermatous GVHD may occur without a preceding lichenoid stage. Clinical heterogeneity is common, although sclerodermatous GVHD has a predilection for the limbs. Treatment options are largely unsatisfactory if conventional immunosuppression fails. PUVA may give some symptomatic benefit and extracorporeal photopheresis seems to be less efficacious than previously published work suggests.

p-Phenylenediamine allergy: the role of Bandrowski's base

p-Phenylenediamine (PPD) is a commonly used hair-dye and a potent skin allergen. The mechanism of sensitization is unknown, as PPD is protein unreactive. We studied Bandrowski's base (BB), a PPD trimer, as well as 1,4-benzoquinone (BQ), a PPD hapten. PPD patch-test positive patients were patch-tested to BB and BQ. All tests were negative to 0.01% BQ and 0.01% BB. Five of 14 (35.7%) tested had true positive reactions to 0.1% BQ. One percent BQ was found to be irritant. Seven of 43 tested (16%) were positive to either 0.1% or 1% BB. The positive reactions to BB were weak, even when PPD reactions were strong. Mice lymph node assay gave EC3 values of 0.14% for PPD compared with 0.03% for BB. Therefore, BB is approximately 10 times more potent than PPD, taking into account the molarity. We suggest that while PPD may act as a prohapten, there is probably a spectrum of antigenic determinants in vivo. BB may be bound or metabolized by keratinocytes before it reacts with Langerhans cells.

Cutaneous manifestations of granulocyte colony-stimulating factor

Granulocyte colony-stimulating factor (GCSF) is a recombinant human growth factor widely used in haematology. It is known to cause cutaneous vasculitis and neutrophilic dermatoses. We present three cases of Sweet's syndrome (SS) associated with GCSF use. Raised GCSF levels have been demonstrated in patients with SS. GCSF is the best understood mechanism by which neutrophil accumulation occurs and shows a dose-dependent effect in provoking SS.

Koebnerizing sclerodermatous graft-versus-host disease caused by donor lymphocyte infusion and interferon-α

Graft-versus-host disease (GvHD) is a common sequel to allogeneic bone marrow transplants, which may be accompanied by desirable graft-versus-tumour effects. Sclerodermatous GvHD is a rare subtype that is very difficult to treat. We report the first case of sclerodermatous GvHD as part of the Koebner phenomenon. We propose that donor lymphocyte infusion and interferon-alpha were involved in the pathogenesis of this case.

A novel case of linear syringomatous hamartoma

A 4-year-old girl presented with a linear, indurated area of dusky erythema and hyperpigmentation down the left leg, present since birth. Histology suggested syringomata. The clinical course and appearances suggest a novel entity for which we have coined the term 'linear syringomatous hamartoma'.

Eczema-like plaques secondary to enoxaparin

Low-molecular-weight heparins are used extensively in acute medicine. They are generally well tolerated but may cause a rare, eczema-like type IV hypersensitivity reaction. We report 3 cases of this eruption and speculate that it may be significantly under-reported due to misidentifying the causal drug, which may have serious consequences. We discuss treatment alternatives such as fondaparinux sodium, which may rarely cross-react.

Cutaneous leishmaniasis: three children with Leishmania major successfully treated with itraconazole

We report the rare instance of four family members with numerous cutaneous lesions of Leishmania major contracted while on holiday in Algeria. Treatment was successful with oral itraconazole for the children and intralesional sodium stibogluconate for the mother. Cutaneous leishmaniasis should be considered in those with apparently sterile plaques returning from endemic areas. These results suggest that itraconazole, which is ideally suited for use in children, is an effective monotherapy for L. major.

Lues maligna

The incidence of syphilis in the UK is rising, particularly in HIV-positive men. We describe a Caucasian, HIV-negative woman who presented with secondary syphilis taking the form known as lues maligna. She also demonstrated the prozone phenomenon whereby the rapid plasmin reagin test was negative, but the Venereal Disease Research Laboratory and Treponema pallidum haemagglutination tests were positive.

Haemorrhagic bullae in a case of paroxysmal nocturnal haemoglobinuria

Paroxysmal nocturnal haemoglobinuria is a clonal stem cell disorder manifesting as haemolysis, bone marrow failure and thrombosis. We report a rare cutaneous manifestation on the trunk of a 40-year-old patient. Skin biopsy revealed the presence of fibrin thrombi in the capillaries. The eruption responded within days after commencing oral corticosteroids.

Severe generalized argyria secondary to ingestion of colloidal silver protein

Argyria is a rare cause of cutaneous discolouration caused by silver deposition. We report a case of dramatic and diffuse argyria secondary to ingestion of colloidal silver protein over a 1-year period. Stained electron microscopy with spectral analysis was used to confirm the clinical diagnosis. Silver-protein complexes are deposited in the skin and reduced to inert silver salts by sunlight in a process similar to that harnessed in photography. Our patient had obtained the silver for consumption via mail order. It had been advertised as a cure for a variety of diseases. Colloidal silver protein is commercially available as a 'food supplement', hence circumventing the strict controls placed on medicines.