Identifying the best predictive diagnostic criteria for psoriasis in children (< 18 years): a UK multicentre case-control diagnostic accuracy study (DIPSOC study).

BACKGROUND: In children, psoriasis can be challenging to diagnose. Difficulties arise from differences in the clinical presentation compared with adults. OBJECTIVES: To test the diagnostic accuracy of previously agreed consensus criteria and to develop a shortlist of the best predictive diagnostic criteria for childhood psoriasis. METHODS: A case-control diagnostic accuracy study in 12 UK dermatology departments (2017-2019) assessed 18 clinical criteria using blinded trained investigators. Children (< 18 years) with dermatologist-diagnosed psoriasis (cases, N = 170) or a different scaly inflammatory rash (controls, N = 160) were recruited. The best predictive criteria were identified using backward logistic regression, and internal validation was conducted using bootstrapping. RESULTS: The sensitivity of the consensus-agreed criteria and consensus scoring algorithm was 84·6%, the specificity was 65·1% and the area under the curve (AUC) was 0·75. The seven diagnostic criteria that performed best were: (i) scale and erythema in the scalp involving the hairline, (ii) scaly erythema inside the external auditory meatus, (iii) persistent well-demarcated erythematous rash anywhere on the body, (iv) persistent erythema in the umbilicus, (v) scaly erythematous plaques on the extensor surfaces of the elbows and/or knees, (vi) well-demarcated erythematous rash in the napkin area involving the crural fold and (vii) family history of psoriasis. The sensitivity of the best predictive model was 76·8%, with specificity 72·7% and AUC 0·84. The c-statistic optimism-adjusted shrinkage factor was 0·012. CONCLUSIONS: This study provides examination- and history-based data on the clinical features of psoriasis in children and proposes seven diagnostic criteria with good discriminatory ability in secondary-care patients. External validation is now needed.

Bronchiolitis obliterans as a long-term sequela of Stevens-Johnson syndrome and toxic epidermal necrolysis in children.

Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are characterized by widespread skin and mucosal blistering and necrosis. The triggers and long-term sequelae in children may differ from those reported for adults. Bronchiolitis obliterans (BO) is an uncommon complication, with only 15 previously reported cases, but can lead to significant long-term morbidity, requiring lung transplantation in some cases. We report three children with nondrug-related SJS (n = 1) and TEN (n = 2) who developed BO. Two were treated with intravenous immunoglobulin therapy (2-2.4 g/kg) and all three survived. We highlight salient learning points from our cases and potential pitfalls in diagnosis of BO, including delayed onset, and we also review the literature.

Vemurafenib-induced hyperkeratosis of the areola treated with topical adapelene.

We present a rare condition, hyperkeratosis of the areola, induced by vemurafenib. Only a few papers have described an association of BRAF inhibitors with hyperkeratosis of the areola and/or nipple. Vemurafenib is a selective BRAF inhibitor used in patients with unresectable or metastatic melanoma who are positive for the V600 mutation. This drug has been associated with numerous cutaneous side effects, both benign and malignant. We report a male patient with vemurafenib-induced hyperkeratosis of the areola managed successfully with a topical retinoid, and describe for the first time a treatment for this side effect.

X-linked dyskeratosis congenita presenting in adulthood with photodamaged skin and epiphora.

Dyskeratosis congenita (DC) is a clinically and genetically heterogeneous multisystem bone marrow failure disorder of telomere maintenance, which may present with dermatological features. The main cause of mortality is bone marrow failure, often developing in the second decade of life, although pulmonary disease and malignancies such as squamous cell carcinomas (SCCs) may also prove fatal. We report the case of a 28-year-old man with X-linked DC and confirmed DKC1 gene mutation. In addition to the classic triad of nail dystrophy, hyperpigmentation and oral leucoplakia, the patient had actinic keratosis (AK) and photodamaged skin, hitherto under-recognized features of this condition. Awareness of the clinical presentation of DC is important, as accurate clinical and molecular diagnosis affords patients and their families genetic counselling, cancer prevention and screening measures, and planning for complications such as bone marrow failure.

A congenital smooth muscle hamartoma masquerading as a reticulate vascular naevus.

Smooth muscle hamartoma (SMH) is a benign congenital or acquired hamartomatous lesion comprising a dermal proliferation of smooth muscle bundles. We report a case of congenital SMH with an unusual clinical appearance. A 3-year-old girl presented with an asymptomatic atrophic linear lesion on the posterior surface of her right thigh, which had been present since birth. The striking resemblance to a vascular lesion initially led to the erroneous clinical diagnosis of atrophic reticulate vascular naevus. However, a skin biopsy showed typical features of SMH. To our knowledge, SMH with linear configuration has only been described in two previous cases, and there are no previous reports of SMH with such a marked resemblance to a vascular lesion.

Toxic epidermal necrolysis: retrospective analysis of 21 consecutive cases managed at a tertiary centre.

BACKGROUND: Toxic epidermal necrolysis (TEN) is a rare, severe blistering disease. Outcome data in British patients is limited to case reports or small series. AIMS: To characterize the aetiology, clinical features, complications and outcome in TEN, and to evaluate the effect of treatments including intravenous immunoglobulin (IVIg). METHODS: This was a retrospective study of 21 consecutive patients with histologically confirmed TEN presenting between 1995 and 2007 to a tertiary referral unit for TEN in a university hospital in the UK. RESULTS: The mean age of the patients was 53.5 years. The mean surface area of denuded skin was 44% (range 30-90%). An adverse drug reaction was implicated in all patients, with mean time of TEN onset being 17 days (range 2-41 days) after initial drug exposure. The SCORTEN index was calculated in 19 patients (median SCORTEN 3, range 2-5). The SCORTEN predicted 7.3 deaths in this cohort, and 7 deaths were seen in the group of patients for whom SCORTEN was calculated. The overall mortality was 8/21 (38%). Ten patients received corticosteroids before transfer to our centre. In the steroid-treated group 4/10 patients (40%) died, and 4/11 patients (36%) who were not treated with steroids also died. Between 1995 and 2000, patients were treated with cyclophosphamide 1.5 mg/kg/day (n=2; both died) and subsequently with ciclosporin 2.5-4 mg/kg/day (n=3; 2 deaths). From 2000, patients were treated with IVIg 0.4-1 g/kg/day (n=14; 3 deaths); the SCORTEN-predicted mortality in this group was 5 deaths. Complications included sepsis (n=18), and organisms included Enterococcus, Acinetobacter, Staphylococcus aureus and methicillin-resistant S. aureus strains). Other complications included anaemia (n=17), lymphopenia (n=11) and neutrophilia (n=9). The presence of neutropenia (n=6; 4 deaths), renal impairment (n=5; 4 deaths) and disseminated intravascular coagulation (n=4; all died) were strong risk factors for mortality. Of 12 patients with ocular involvement, 6 (50%) developed symblepharon and/or visual impairment. CONCLUSIONS: This study confirmed the validity of SCORTEN in our series. In the subgroup treated with IVIg, there were three deaths, compared with the SCORTEN predicted mortality of five deaths. Corticosteroids did not seem to be beneficial.