https://www.jidonline.org/article/S0022-202X(15)36098-X/pdf

Global Epidemiology of Psoriasis: A Systematic Review of Incidence and Prevalence

To inform the WHO Global report on psoriasis, a new comprehensive worldwide systematic review of the epidemiology of psoriasis was undertaken. The aim of this study was to systematically review the worldwide literature regarding the epidemiology of psoriasis, including prevalence and incidence, in adults and in children. A search of 15 electronic medical databases was performed. Using a rigorous systematic protocol, eligible articles were analysed. No language, regional or temporal restrictions were applied. A total of 76 study observations met all eligibility criteria and were included in the systematic review. The estimates of the prevalence of psoriasis in adults ranged from 0.51% to 11.43%, and in children from 0% to 1.37%. Psoriasis is a common disease, occurring more frequently with advancing age. Limited data on the epidemiology of psoriasis are available. The available prevalence data come from only 20 countries, meaning there are huge geographic gaps in knowledge, especially from low- and middle-income settings.

A systematic review of worldwide epidemiology of psoriasis

Summary
Acne is estimated to affect 9·4% of the global population, making it the eighth most prevalent disease worldwide. Epidemiological studies have demonstrated that acne is most common in postpubescent teens, with boys most frequently affected, particularly with more severe forms of the disease. This paper aims to provide an update on the epidemiology of acne worldwide. Recent general and institutional studies from around the world have shown that the prevalence of acne is broadly consistent globally (with the exception of specific populations, which are discussed). However, this review highlights that there is a wide range of disparate outcome measures being applied in epidemiology studies, and we emphasize the need to develop a widely accepted, credible, standard assessment scale to address this in the future. In addition we discuss special populations, such as those devoid of acne, as well as the impact of potential determinants of acne on disease epidemiology.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/bjd.13462

A global perspective on the epidemiology of acne.

Background Vitiligo is an acquired, idiopathic, and worldwide common depigmentation disorder with an estimated prevalence from 0.1 to 8%. These numbers are based on clinical population studies and field research examining inhabitants of geographically enclosed areas. Our aim was to collect all available data on the prevalence of vitiligo in the general population, paying particular attention to children/adolescent groups and adults.

Materials and methods  Screening of available literature and online databases using several key words.

Results  We found more than 50 studies that used several methods and subgroups of the general population. The prevalence of vitiligo ranges from 0.06 to 2.28%, whereas this was 0.0–2.16% in children/adolescents populations.

Conclusions  The often cited prevalence of 8% could not be confirmed after excluding clinical patient populations. Accordingly, the worldwide prevalence of vitiligo ranges between 0.5 and 2%.

http://www.vitiligo.eu.com/jordan_trip/publications/Krueger_Prevalence_Review_2012.pdf

A review of the worldwide prevalence of vitiligo in children/adolescents and adults.

Scabies is a skin disease that, through secondary bacterial skin infection (impetigo), can lead to serious complications such as septicaemia, renal disease, and rheumatic heart disease. Yet the worldwide prevalence of scabies is uncertain. We undertook a systematic review, searching several databases and the grey literature, for population-based studies that reported on the prevalence of scabies and impetigo in a community setting. All included studies were assessed for quality. 2409 articles were identified and 48 studies were included. Data were available for all regions except North America. The prevalence of scabies ranged from 0·2% to 71·4%. All regions except for Europe and the Middle East included populations with a prevalence greater than 10%. Overall, scabies prevalence was highest in the Pacific and Latin American regions, and was substantially higher in children than in adolescents and adults. Impetigo was common, particularly in children, with the highest prevalence in Australian Aboriginal communities (49·0%). Comprehensive scabies control strategies are urgently needed, such as a community-based mass drug administration approach, along with a more systematic approach to the monitoring of disease burden.

https://www.thelancet.com/pdfs/journals/laninf/PIIS1473-3099(15)00132-2.pdf

Prevalence of scabies and impetigo worldwide: a systematic review

Background Few epidemiological surveys have been carried out to determine the prevalence of skin diseases in the population of Egypt, particularly “Upper Egypt”. So it is a pressing necessity to conduct such a study in rural Assiut.



Objectives  To determine the prevalence of various skin diseases in rural Assiut.



Subjects and methods  A cross-sectional community-based survey was followed. The survey included 8008 rural inhabitants of all ages and both sexes from a representative of three villages of Assiut Governorate, Upper Egypt. The data were collected through personal interview and examination at homes from December 1994 to December 1996.



Results  They showed that 6961 (86.93%) of the studied population had one or more skin diseases. The group with parasitic skin infestations had the highest prevalence rate (27.40%) of the total sample, of which pediculosis capitis (19.37%) was the commonest. Eczema/dermatitis group had a rate of 19.82%, with pityriasis alba forming the majority (13.49%). Pigmentary disorders were 17.68%, followed by fungal skin infections (16.17%), then naevoid disorders (16.10%), hair and scalp disorders (12.07%), bacterial skin infections (10.10%), sweat gland disorders (6.16%), acne vulgaris (5.37%). Leprosy constituted 1.6/10,000. Other various skin disorders were recorded.



Conclusions  Infective-parasitic diseases were a major problem particularly among the younger age-group and those of low socio-economic status.

http://www.skincareforall.org/wp-content/uploads/2012/10/19.-Prevalence-of-skin-diseases-in-rural-areas-of-Assiut-Governorate-Upper-Egypt.pdf

Prevalence of skin diseases in rural areas of Assiut Governorate, Upper Egypt

Background Acne vulgaris is a common skin disease. Although neither life threatening nor physically debilitating, acne can severely affect social and psychologic functioning.

Aim  To study the overall impact of acne vulgaris on the quality of life and psychologic functioning of patients in Egypt.

Methods  One hundred and fifty patients with acne vulgaris and 50 healthy controls were evaluated. Acne patients were evaluated using the Dermatology Life Quality Index (DLQI), Culture Free Self-Esteem Inventory – Adult Version (CFSEI-AD), and Symptom Check List-90 – Revised (SCL-90-R). The controls were evaluated using SCL-90-R and CFSEI-AD.

Results  The mean DLQI scores of male acne patients were found to be higher than those of female patients with regard to symptoms and feelings, daily activities, personal relationships, and treatment; however, the differences were significant for leisure (P = 0.005) and total score (P = 0.022) only. The CFSEI-AD score of patients was significantly lower than that of controls (P = 0.001). Acne patients had significantly higher scores than controls in all items of the SCL-90-R. Significant positive correlations were found between the duration and severity of illness and DLQI and SCL-90-R scores. There was a significant negative correlation between the duration and severity of acne and CFSEI-AD scores.

Conclusion  Acne vulgaris has a significant effect on the quality of life. Our results highlight the importance of recognizing psychiatric comorbidity in acne patients.

The impact of acne vulgaris on the quality of life and psychologic status in patients from upper Egypt.

Some immunologic studies were carried out for 31 patients with pityriasis rosea. Normal levels of serum IgG and IgA but higher levels of IgM were obtained. Serum C3 values were decreased while C4 values were normal. B lymphocytes showed no difference from the controls, whereas T-cell counts were significantly lower in the patients. The migration inhibition indices were higher in the patients than the controls. Direct immunofluorescence tests were negative in the studied three cases. The possible implication of a viral infection in the production of the reported changes was discussed.

Kamal Abdel-Hafez

Papers

Prevalence of skin diseases in rural areas of Assiut Governorate, Upper Egypt

The impact of acne vulgaris on the quality of life and psychologic status in patients from upper Egypt.

Pityriasis rosea. An immunologic study.