Abnormal Pubertal Development   Dennis M. Styne and Leonna Cuttler   SEXUAL PRECOCITY AND EARLY PUBERTY Sexual precocity is the general term for early puberty. Isosexual precocity refers to a…

Movement Disorders, Tics, and Tourette Syndrome   Diana Apetauerova   Movement disorders are defined as either a loss or poverty (akinesia) or slowness (brady-kinesia) of movement that is not associated…

Juvenile Idiopathic Arthritis   OLIGOARTICULAR, POLYARTICULAR, AND SYSTEMIC CATEGORIES Carol A. Wallace, David A. Cabral, and Robert P. Sundel   Arthritis is a clinical finding of persistent joint swelling or…

Periodontal and Gingival Health and Diseases   Nadeem Y. Karimbux and David M. Kim   The normal periodontium consists of gingiva, connective tissue, the periodontal ligament, cementum, and the surrounding…

Disorders of Creatine and Ornithine Metabolism   Sylvia Stockler-Ipsiroglu   CREATINE METABOLISM Creatine is synthesized mainly in the liver and pancreas by the action of arginine:glycine amidinotransferase (AGAT) and guanidinoace-tate…

Leprosy   Wayne M. Meyers, Françoise Portaels, and Douglas S. Walsh   Leprosy is a chronic infectious disease caused by Mycobacterium leprae, an acid-fast bacillus (AFB). It was first recognized…

Environmental Causes of Birth Defects   Elizabeth Balken, Marsha Leen-Mitchell, Lynn P. Martinez, and Julia A. Robertson   The definition of a teratogenic agent (an exposure, external to the fetal…

Lysosomal Storage Disorders   Irina A. Anselm   Lysosomal storage disorders (LSDs) comprise a group of approximately 30 relatively rare inherited diseases that are characterized by defective functioning of one…

Nose and Sinus   Ellen S. Deutsch and Cecille G. Sulman   ANATOMY AND EMBRYOLOGY The nose is the major portal of air exchange between the internal and external environment….

Germ Cell Tumors   Thomas A. Olson   Germ cell tumors are infrequent tumors in childhood and adolescence. These neoplasms comprise 2% to 3% of all tumors diagnosed in children…