Infected intracranial dermal sinus tract in a child.

Dermal sinus tracts (DSTs) are rare congenital defects occurring along the cranial spinal axis. They may extend from the skin into the deeper structures of the central nervous system. While most DSTs remain clinically occult, they can provide a route of entry for skin pathogens to cause intracranial infection. We report a child with a recent history of fever of unknown etiology who presented to our emergency department with a subcutaneous occipital mass. She was ultimately diagnosed with an infected intracranial dermal sinus tract. In this report, we provide a review of the literature on the diagnosis and management of this unique entity.

Identification and analysis of the bacterial endosymbiont specialized for production of the chemotherapeutic natural product ET-743.

Ecteinascidin 743 (ET-743, Yondelis) is a clinically approved chemotherapeutic natural product isolated from the Caribbean mangrove tunicate Ecteinascidia turbinata. Researchers have long suspected that a microorganism may be the true producer of the anticancer drug, but its genome has remained elusive due to our inability to culture the bacterium in the laboratory using standard techniques. Here, we sequenced and assembled the complete genome of the ET-743 producer, Candidatus Endoecteinascidia frumentensis, directly from metagenomic DNA isolated from the tunicate. Analysis of the ∼ 631 kb microbial genome revealed strong evidence of an endosymbiotic lifestyle and extreme genome reduction. Phylogenetic analysis suggested that the producer of the anti-cancer drug is taxonomically distinct from other sequenced microorganisms and could represent a new family of Gammaproteobacteria. The complete genome has also greatly expanded our understanding of ET-743 production and revealed new biosynthetic genes dispersed across more than 173 kb of the small genome. The gene cluster's architecture and its preservation demonstrate that the drug is likely essential to the interactions of the microorganism with its mangrove tunicate host. Taken together, these studies elucidate the lifestyle of a unique, and pharmaceutically important microorganism and highlight the wide diversity of bacteria capable of making potent natural products.