Search

Inger LH Dorf,1 Sigrún AJ Schmidt,1,2 Mette Sommerlund,1 Uffe Koppelhus1 1Department of Dermatology, Aarhus University Hospital, Aarhus, Central Region Denmark, Denmark; 2Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Central Region Denmark, DenmarkCorrespondence: Inger LH DorfDepartment of Dermatology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, Aarhus, 8200, DenmarkTel +45 7846 1861Email inger.dorf@live.dkPurpose: Darier’s disease (DD) is a rare genetic skin disease, characterized by yellow-brown, scaly, crusted papules in seborrheic areas and specific nail changes. This study aimed to validate all first-time diagnoses of DD in Danish National Patient Registry (DNPR). The intent of the study is validation of DNPR for epidemiological and clinical studies on DD.Patients and Methods: We identified all patients in DNPR who received their first-time diagnosis of DD between January 1, 1977 and December 31, 2018 (International Classification of Diseases [ICD]-8 code 75721 until the end of 1993: ICD-10 code Q828F thereafter). We restricted to diagnoses from departments of dermatology, where these patients are managed. We validated diagnoses against information from medical records, using predefined data extraction sheets and validation criteria. We classified diagnoses as probable when characteristic clinical features were present; confirmed when there was also genetic confirmation, histopathological confirmation and/or positive family history, or rejected (remaining patients). We estimated positive predictive values (PPVs) with 95% confidence intervals (CIs) for diagnoses overall and stratified by ICD classification, sex, age at diagnosis, year of diagnosis, type of diagnosis, and type of contact.Results: We identified 277 first-time diagnoses of DD, of which 229 (82.7%) stemmed from departments of dermatology. Medical records were available for 196 (85.6%) of these. The overall PPVs for probable and confirmed DD were 89.3% (95% CI: 84.2– 92.9) and 81.1% (95% CI: 75.1– 86.0), respectively. The PPV for probable ICD-8 diagnosis (95.8% (95% CI: 82.1– 99.5)) was slightly higher than that of probable ICD-10 diagnosis (88.4% (95% CI: 82.7– 92.3)).Conclusion: The validity of first-time diagnoses of DD recorded by departments of dermatology in the DNPR is relatively high, making DNPR suitable for epidemiological studies on DD in Denmark, as well as a useful source for recruitment to clinical studies on DD.Keywords: Denmark, diagnosis, dyskeratosis follicularis, health administrative data, registration, validity

Aquagenic wrinkling of the palms was first described in 1974. This review summarises the present knowledge. Aquagenic wrinkling of the palms is most often associated with cystic fibrosis, but several other associated conditions are described. Patients report of pruritus, pain and discomfort in the palms after contact with water, and excessive wrinkling is visible. The prognosis is good, and symptoms often decrease in adulthood. A positive water exposure test will support the diagnosis, and the patient should be referred for dermatological investigation and genetic test for cystic fibrosis should be offered.

Ichthyosis – also called fish scale disease – is a group of skin diseases, which are characterised by xerosis and scaling. Most commonly, the diseases are genetically inherited, but an acquired type also exists. Ichthyosis vulgaris (IV), is the most common type, affecting 1:250 individuals. Diagnosing IV can be challenging, because its clinical features are subject to great variation, ranging from mild cases with slight xerosis to severe cases with marked scaling and formation of fissures.

Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder with highly varying disease manifestations, many of which cause extensive morbidity. There are international consensus criteria for the diagnosis, monitoring and treatment of TSC, and approved medical treatment for some of the most serious disease manifestations. However, organisation of a rational and coordinated care of TSC patients involves many different medical specialities and is only sparsely described. This review describes the interdisciplinary care of TSC patients at Aarhus University Hospital, Denmark.

Mattias Hedegaard Kristensen,1 Sigrun Alba Johannesdottir Schmidt,2 Line Kibsgaard,1 Hanne Hove,3 Mette Sommerlund,1 Uffe Koppelhus1 1Department of Dermatology, Aarhus University Hospital, Aarhus, Denmark; 2Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark; 3Centre for Rare Diseases, Copenhagen University Hospital, Copenhagen, DenmarkCorrespondence: Uffe KoppelhusDepartment of Dermatology, Aarhus University Hospital, F3, Plan 2,202,Palle Juul-Jensens Boulevard 99, DK 8200, DenmarkTel +45 2494 6245Fax +45 7846 1860Email Uffekopp@rm.dkPurpose: Inherited ichthyosis is a monogenetic disease characterized by hyperkeratosis and scaling of the skin, with large interindividual variation in severity. It can affect quality of life for patients and their families. Population-based data on inherited ichthyosis are lacking, which hampers studies into its epidemiology.Patients and Methods: Based on medical record review, we validated diagnoses of inherited ichthyosis in two nationwide population-based registries commonly used for epidemiological research: The Danish National Patient Registry and the Danish Pathology Registry. The study period was January 1, 1977, through December 31, 2015. Validation samples were taken from one regional hospital without a specialized dermatological department and two specialized dermatological departments. Positive predictive values (PPVs) were estimated overall and for each coding system (ICD-8, ICD-10 and SNOMED), including for specific ICD-10 codes.Results: We identified 1772 first-time diagnoses of inherited ichthyosis; 363 patients were diagnosed at the departments selected for validation, and 307 of these patients (84.6%) had medical records enabling validation. We observed an overall PPV of 73.3% (95% CI: 68.1– 77.9). For ICD-8, ICD-10, and SNOMED diagnoses, the PPVs were 73.2% (95% CI: 58.1– 84.3), 74.7% (95% CI: 69.0– 79.7), and 46.2% (95% CI: 22.1– 71.7), respectively. In analyses for ICD-10 diagnoses, we observed much higher validity of diagnoses from the specialized departments (PPV 79.7%; 95% CI: 74.1– 84.3) than the regional hospital (PPV 5.9%; 95% CI: 0.6– 24.3). The PPVs for specific diagnoses were 80.1% for ichthyosis vulgaris and 96.6% for X-linked ichthyosis but below 45% for remaining, rarer, subtypes.Conclusion: The PPV of first-time diagnosis of inherited ichthyosis made at specialized dermatological departments in the Danish National Patient Registry is approximately 80%. Diagnoses from the Danish Pathology Registry had low PPVs precluding their use for research.Keywords: Denmark, diagnosis, ichthyosis, health administrative data, registration, validity