Xeroderma pigmentosum (XP, OMIM 278700-278780) is a group of autosomal recessive diseases characterized by hypersensitivity to UV rays. There are seven complementation groups of XP (XPA to XPG) and XPV. Among them, the XP group C (XP-C) is the most prevalent type in Western Europe and in the United States. We report here on the clinical and genetic investigation of XP-C patients in 14 Tunisian families. As the XPC V548A fs X572 mutation has been identified in Algerian and Moroccan populations, Tunisian patients were first screened for this mutation by a direct sequencing of exon 9 of the XPC gene. All patients with a severe clinical form had this mutation, thus showing the homogeneity of the mutational spectrum of XPC in Tunisia. A potential founder effect was searched and confirmed by haplotype analysis. Taking into account the similarity of the genetic background, we propose a direct screening of this mutation as a rapid and cost-effective tool for the diagnosis of XP-C in North Africa.

Mutations in Ha-ras, Ki-ras, and N-ras genes in squamous and basal cell carcinomas in patients with xeroderma pigmentosum (XP) were examined by the polymerase chain reaction followed by single-strand conformation polymorphism analysis and direct base sequencing. No mutation was detected in codons 12, 13, and 61 of the ras genes in XP skin tumors. This was in contrast with previous findings of a high frequency of mutation in the p53 gene in skin tumors in XP patients. A novel mutation in codon 6 of the Ki-ras gene was detected in a squamous cell carcinoma. The mutation was a C-->T transition at a dipyrimidine (5'-CT) sequence and could have been produced by solar ultraviolet light. The mutated ras gene did not have the ability to transform NIH/3T3 cells. In three tumors, multiple base substitutions were detected in exon 1 of the Ki-ras and N-ras genes. These results and our previous work on p53 gene mutations suggest that mutations in ras genes are far less frequent than in the p53 gene in the skin tumors in XP patients and that ras genes are less important in skin tumorigenesis in XP patients than is the p53 gene.

No abstract

The objective of the study was to evaluate the efficacy of intramuscular penicillin: mixture of benzyl penicillin and procain penicillin (2 MU x 2 times daily) and intravenous benzyl penicillin (4 MU x 6 times daily) in the treatment of hospitalized adult patients with erysipelas. A prospective randomized unicentric trial was conducted. In total, 112 patients entered the study; 57 in the intramuscular group and 55 patients in the intravenous group completed the trial. The failure rate was 14% for intramuscular group and 20% for the intravenous group (P = 0.40). Local complications such as of the leg abscesses were observed in the two groups (intravenous 9.1%, intramuscular 7%; P = 0477). Of the patients treated with intravenous benzyl penicillin, 25.5% presented complications related to the route (venitis). Intramuscular penicillin should be considered an effective and well-tolerated treatment of erysipelas in adult patients.

Xeroderma pigmentosum (XP) is a rare disorder characterized by a high skin sun-sensitivity predisposing to skin cancers at an early age. Among Tunisian XP patients with an intermediate skin phenotype, 92% presented neurological abnormalities related to XPA gene deficiency. Clinical variability of the XP-A phenotype is associated with a mutational heterogeneity. In the present study, two Tunisian families with severe dermatological and neurological XP phenotypes were investigated in order to determine clinical characteristics and genetic basis. Two Tunisian families with four XP affected children were examined in the Dermatology Department. Clinical features showed severe presentation of the disease. Coding regions of the XPA gene were analysed by direct sequencing. Results showed the presence of a novel mutation, p.E111X, in three patients belonging to the same family and presenting a very severe phenotype i.e. development of skin lesions and neurological signs before 1 year age. For the other patient, we identified a nonsense mutation, p.R207X, already identified in a Palestinian XP-A patient. Identification of novel causing mutations in Tunisian XP-A patients shows the genetic and mutational heterogeneity of the disease in Tunisia. Despite a relatively homogenous mutational spectrum, mutational heterogeneity for rare cases is observed because of the high rate of consanguinity.