Related Experiment Video
Updated: Jul 15, 2026

Minimal Erythema Dose MED Testing
Published on: May 28, 2013
Xeroderma pigmentosum in Yemen
1Department of Dermatology, Saudi Hospital at Hajjah, Sana'a, Republic of Yemen.
Background:
The incidence of xeroderma pigmentosum (XP) in Yemen seems to be quite high but there are no previous reports.
Objective:
To study the clinicoepidemiologic aspect of XP in Yemen.
Methods:
All 40 patients (24 male and 16 female patients from 32 families) treated and followed between 1997 and 2014 were subjected to detailed analysis with the help of a standardized protocol. The diagnosis was based on clinical features and histopathologic data, when needed. The diagnosis of tumors was confirmed by histopathologic examination in all cases.
Results:
The median age of onset of initial manifestations was 9.5 months, and that of malignant lesions was 7 years. Parents of the patients were not affected, but history of consanguinity was recorded in 38. Initial lesions, such as dryness of the skin and freckles on the face, were noticed in all patients. In addition, erythema of the face with photosensitivity was observed in 21 patients. Premalignant and malignant skin lesions observed later were actinic keratosis in 15 patients, lentigo maligna in one, squamous cell carcinoma (SCC) in 10, and basosquamous carcinoma in one. Eyes were affected with SCC in seven and malignant melanoma (MM) in two patients. SCC of the lip developed in two patients and that of the tongue in one patient. Judicious use of acitretin in 12 patients showed good result.
Conclusion:
XP in Yemen is characterized by a relatively high incidence, high percentage of consanguinity in parents of the patients, early onset of initial manifestations, malignant tumors, and severe ocular and oral lesions. Acitretin showed good result.
Related Concept Videos
Nucleotide Excision Repair
Nucleotide Excision Repair
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Pigmentation
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
Changes in Skin Color: Clinical Perspectives
Albinism
Albinism is a genetic disorder that affects (completely or partially) the coloring of skin, hair, and eyes. The defect is primarily...
Skin Cancer
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Leishmaniasis

