Facial discoid dermatosis: A cosmetically disfiguring and challenging condition to treat.

Facial discoid dermatosis (FDD) is a recently described condition comprising discrete facial papulo-squamous lesions. We report three cases that clinically and histologically resemble FDD and demonstrate its resistance to treatment. Awareness of this new clinical entity will allow early diagnosis and the ability to make patients aware that there is unlikely to be a successful treatment. However, our study suggests that although FDD can persist for many years, it appears to remain stable.

Interleukin-10 receptor mutation presenting with severe nappy ulceration and infantile inflammatory bowel disease.

Inflammatory bowel disease (IBD) can be divided into Crohn disease, ulcerative colitis and inflammatory bowel disease unclassified (IBDU). In most patients, these disorders present in adolescence or early adulthood. Patients with infantile IBD can have an associated underlying immunodeficiency disorder caused by a mutation in interleukin (IL)-10 or its receptor. We describe a child presenting with intractable bloody diarrhoea since 2 weeks of age and with severe nappy ulceration, who was ultimately diagnosed as having inflammatory bowel disease (IBD) due to an immunodeficiency in the IL-10 receptor. This report highlights the importance of considering this rare immunodeficiency in patients with infantile IBD presenting with severe perianal disease to a dermatologist.

Acral peeling skin syndrome associated with a novel CSTA gene mutation.

Acral peeling skin syndrome (APSS) is a rare autosomal recessive condition, characterized by asymptomatic peeling of the skin of the hands and feet, often linked to mutations in the gene TGM5. However, more recently recessive loss of function mutations in CSTA, encoding cystatin A, have been linked with APSS and exfoliative ichthyosis. We describe the clinical features in two sisters with APSS, associated with a novel large homozygous deletion encompassing exon 1 of CSTA.

Calciphylaxis in a patient with alcoholic liver disease in the absence of renal failure.

Calciphylaxis is a rare, potentially life-threatening syndrome characterized by progressive microvascular and superficial soft tissue calcification, usually seen in patients with chronic renal failure. We describe an unusual case of calciphylaxis in a patient with alcoholic liver disease and normal renal function who responded well to conservative wound care.

Management of large birthmarks.

Birthmarks are commonly seen in neonates. Most are insignificant incidental findings and straightforward in their diagnosis and management. Others are of more serious concern and may require intervention for medical or cosmetic reasons. They may also be an indication of abnormalities in other organ systems. This chapter will focus on the diagnosis and management of large vascular and pigmented birthmarks. A multidisciplinary team approach involving paediatricians, dermatologists, plastic surgeons and other specialists is often required in the management of these children.

A keratin 14 'knockout' mutation in recessive epidermolysis bullosa simplex resulting in less severe disease.

Epidermolysis bullosa simplex (EBS) is a blistering skin disease caused in most cases by mis-sense mutations in genes encoding the basal epidermal keratin (K) 5 and K14. The inheritance is usually autosomal dominant and the mutant keratin proteins appear to exert a dominant negative effect on the keratin intermediate filament cytoskeleton in basal keratinocytes. We report a child with a homozygous K14 mutation resulting in the complete absence of K14 protein in the epidermis; remarkably, he only had mild to moderate disease. Electron microscopy of a skin biopsy showed a marked reduction in numbers of keratin intermediate filaments in the basal keratinocytes. Immunofluorescence microscopy using monoclonal antibody LL001 against K14 showed no staining, suggesting a functional knockout of K14. Sequence analysis of genomic DNA revealed a homozygous mutation in codon 31 of K14 that resulted in a premature stop codon further downstream in exon 1. The child's mother, who is unaffected by the disease, is heterozygous for the mutation. The consanguineous father was unaffected and unavailable for testing. The resulting mRNA is predicted to encode a protein of 116 amino acids, of which the first 30 are identical to the normal K14 sequence, and the remaining 86 residues are mis-sense sequence. Four previously reported cases of autosomal recessive EBS with functional knockout of K14 were severely affected by blistering, in contrast to our patient in whom the predicted protein has only the first 30 amino acids of K14 and is therefore the closest to a true knockout of K14 protein yet identified.

Cutaneous cryptococcus infection due to C. albidus associated with Sézary syndrome.

Cryptococcus albidus is a non-neoformans species of the genus Cryptococcus and is a rare cause of disease. There have been only 13 previously reported cases of systemic disease in which this opportunistic yeast has been isolated from the lung, cerebrospinal fluid and blood. We report the first case of cutaneous Cryptococcus infection due to the species C. albidus, in a man with Sézary syndrome.

Pemphigus vulgaris localized to the vagina presenting as chronic vaginal discharge.

Involvement in pemphigus vulgaris of the female genital tract including the vulva, vagina and cervix has previously been described. In all these cases other cutaneous and mucosal sites have also been affected at some time. We describe a case of pemphigus vulgaris which only involved the vaginal mucosa. The patient presented with a persistent vaginal discharge and examination showed extensive vaginal erosions. Histology of vaginal biopsies was non-diagnostic. The recognition that the vaginal changes may represent an immunobullous disease led to further vaginal biopsies on which direct immunofluorescence studies were performed. These biopsies showed IgG and C3 in the intercellular epidermis, suggesting a diagnosis of pemphigus vulgaris. During the 3-year period that the patient has been under review there have never been any other cutaneous or mucosal lesions. To our knowledge, this is the first case of pemphigus vulgaris localized exclusively to the vaginal mucosa. There was considerable delay in diagnosis and this case highlights how important it is to recognize that chronic mucosal lesions at genital sites may be caused by immunobullous diseases such as cicatricial pemphigoid and pemphigus, and to institute appropriate investigations.

The reproducibility of patch tests.

There is conflicting evidence regarding the reproducibility of patch testing. Discordant results have been reported in up to 44% of cases. The clinical relevance of these discordant patch tests has not been previously assessed. We studied 383 consecutive patients receiving simultaneous duplicate patch testing on opposite sides of the upper back with 10 allergens from the European standard series. Completely discordant patch tests-a negative test on one side with a positive test on the opposite side-were recorded in 30 (8%) patients. Two patients had discordant tests to two of the allergens; 28 had discordant reactions to one allergen. Completely discordant tests were recorded for nickel in 10 (3%) patients, balsam of Peru in two (0.5%), thiomersal in one (0.3%), cobalt in four (1%), paraphenylenediamine in three (0.8%), fragrance mix in two (0.5%), formaldehyde in four (1%), potassium dichromate in two (0.5%), lanolin in three (0.8%) and Kathon CG in one (0.3%). Of those patients with completely discordant patch tests, the allergen was deemed to be a true positive in 11 (3% of total) cases and of possible relevance in a further three. The allergen was felt to be relevant to the presenting complaint in seven (2% of total) patients.