Tungiasis: report of one case and review of the 14 reported cases in the United States.

Tungiasis is a cutaneous parasitic infestation by the fertilized female sand flea Tunga penetrans. It is prevalent in tropical Africa and in Central and South America. Despite increasing air travel to and from these countries, surprisingly the disease is rarely reported in the United States. This report describes another case of tungiasis and reviews the 14 previously reported cases in the United States. Clinical features, differential diagnosis, treatment, and prophylaxis of tungiasis are discussed.

Detection of human teratogenic agents.

Criteria for definition of a human teratogen are similar to Koch's postulates and include (1) presence of the agent during the critical period of development, (2) production of congenital defects by the agent in an experimental animal, and (3) evidence that the agent acts directly on the embryo or fetus. Examples of how teratogens have been identified through specific syndrome identification and by application of experimental animal information are given. Hyperthermia, an example of the latter, is discussed in some detail. Certain bias factors that confound epidemiologic studies are discussed. A system for detection an prevention of human teratogenicity is proposed. The system is based on the integration of three data bases: (1) the exposed parent-child pair, (2) the chemical and biologic effects of the agent, and (3) identification of specific exposure syndromes.

Urethral obstruction malformation complex: a cause of abdominal muscle deficiency and the "prune belly".

Abdominal muscle deficiency with a "prune belly" abdomen as been a major feature of the so-called prune belly syndrome, which has been regarded as a specific entity, although the etiology and developmental pathology are not understood. We present evidence that abdominal muscle deficiency is an etiologically nonspecific anatomic defect which is secondary to fetal abdominal distention of various causes. One of the more common causes is urethral obstruction with consequent early bladder distention, causing abdominal distention and other anomalies, a constellation of findings which we have termed the urethral obstruction malformation complex. This interpretation of the etiology of most cases of prune belly syndrome accounts for the male predominance, the observed variability in severity, and the lack of a defined mode of inheritance. Recurrence risk figures need to be redefined for each specific obstructing lesion of the urethra. The possibility of early prenatal diagnosis and management of fetuses with urethral obstruction needs further study.