Preface| Volume 21, ISSUE 4, SUPPLEMENT , ix, October 2005

Presentation and Management of Urea Cycle Disorders Outside the Newborn Period

      Urea cycle disorders (UCDs) are a group of relatively uncommon inborn errors of metabolism with which most clinicians have little familiarity. As clinical awareness of these disorders has grown, more and more patients are presenting and being diagnosed with UCD-related hyperammonemia outside the more familiar newborn period. These patients often present with perplexing clinical pictures that are explained once the underlying biochemical defect is recognized.
      Symptomatic urea cycle defects may masquerade as chronic illness or a wide range of other neurologic disorders. Symptoms are often seen only when there is a comorbid condition such as an infectious disease or other stress condition. While management of these patients is complex, there are basic principles of diagnosis and treatment that will greatly improve recognition and outcome. This series of articles addresses many of these issues and presents relevant clinical case examples. Treatment issues for both acute and long-term management are discussed, as well as the approaches to diagnosing UCDs in different clinical settings.
      Symptomatic older infants, children, and adults with UCDs will undoubtedly be seen, diagnosed, and treated by critical care personnel. This collection of articles is the result of the second consensus conference on urea cycle treatment held in Toronto on October 25 and 26, 2004, before the annual meeting of the American Society of Human Genetics. The authors and attendees represented a wide range of experience in treating and dealing with urea cycle disease. The papers, presented under the title “Presentation and Management of Urea Cycle Disorders Outside the Newborn Period,” have been compiled in this supplement to Critical Care Clinics.
      We wish to thank Ucyclyd Pharma, a division of Medicis Pharmaceutical Corporation, for its support.