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Xeroderma pigmentosum is a rare autosomal recessive genetic disease characterized by extreme sensitivity due to solar radiation and deficiency in excision repair DNA. Those factors promote a set of skin abnormalities such as keratosis, hyperpigmentation, tumors in areas exposed to sunlight, and ocular and, eventually, neurological disorders. In the present review, we summarize the main clinical features related to a case of xeroderma pigmentosum in a man who was not diagnosed until he was 45 years old.

Human bartonelloses are a group of illnesses of poorly understood pathogenesis. Bartonella henselae is one of the most studied bacterium of its genus. The objective of this study was to observe whether passages of these bacteria, in vivo, would determine ultrastructural changes in them. For this purpose, isogenic mice were inoculated with a standard strain of B. henselae (I). These were initially retrieved from genetically immunodeficient animals (II) and then inoculated in immunocompetent ones. The bacterial colonies obtained (III) were compared, by transmission electron microscopy, with colonies I and II. Loss of fimbriae and an abundant bleb formation were the most common morphological changes found in colony III. Also, on day 6 postinfection, the main histological abnormalities were the endothelial proliferation presented in immunodeficient animals and the incipient granulomata reaction found in one of the immunocompetent inoculated mice, which died spontaneously. These features agree with the Bartonella human disease clinical and histological observations. This study demonstrates that B. henselae in vivo passages induce significant morphological changes in the bacteria and that these abnormalities could explain their seemingly greater virulence. Most of these observations have not been previously described. Thus, further studies on the Bartonella species pathogenesis should consider these data.