Hypervitaminosis A-induced premature closure of epiphyses (physeal obliteration) in humans and calves (hyena disease): a historical review of the human and veterinary literature.

Vitamin A toxicity in the infant, which now occurs rarely from dietary overdosage, was recognized in the 1940s as painful periostitis with rare progression to premature closure of the lower limb epiphyses. Decades later, most cases of vitamin A-induced premature epiphyseal closure (physeal obliteration) occur in pediatric dermatologic patients given vitamin A analogues. This phenomenon resembles a strange disease discovered in more recent years in calves with closed epiphyses of the hind limbs, known as hyena disease. This was a mystery until proved to be caused by vitamin A toxicity from enriched grain that causes the calves to have short hind limbs that resemble those of a hyena and gait disturbance. This historical review links the human and veterinary literature in terms of vitamin A-induced epiphyseal closure using a case report format of a 16-month-old human infant with closed knee epiphyses and gait disturbance that is reminiscent of hyena disease seen in calves.

Polar hysteria: an expression of hypervitaminosis A.

Isotretinoin (Accutane) is a drug closely related to the chemical structure of Vitamin A. The pharmacology and toxicology of these two retinoids is similar enough to warrant comparison. Accutane is a powerful drug which its manufacturer, Roche, indicates is limited for severe recalcitrant nodular acne. This potency is also reflected in Accutane's well-known ability to produce severe birth defects if taken during pregnancy. Less well-known is the risk of this lipid soluble chemical to affect the Central Nervous System. Reports of intracranial hypertension, depression, and suicidal indeation with Accutane use have prompted an examination of this serious and life threatening potential. Though Roche has added a warning to its product label for signs of depression and suicidal ideation, this product is being overprescribed for all forms of acne, including mild cases and moderate acne that have not been treated with alternative medications, which have a lesser risk of depression and suicide. There is no contesting that this drug is effective at clearing up the most severe forms of acne, but the public must be informed of its proper, limited indication for use; depression and suicide can follow in patients with no prior history of psychiatric symptoms or suicide attempts.

Subadult health and disease in prehistoric Tonga, Polynesia.

This article focuses on the differential diagnosis of pathologic lesions recorded on the limbs and crania of 17 subadults from two pre-European burial mounds in Tonga, western Polynesia. All affected subadults were between the ages of 6 months and 3 years at death. The lesions described consist primarily of subperiosteal new bone deposition on the limbs and endocranial surface. However, the presence of cribra orbitalia in a number of individuals indicates concurrent iron-deficiency anaemia. A differential diagnosis of haematogenous osteomyelitis, congenital syphilis, yaws, scurvy, hypervitaminosis A, trauma, Caffey's disease, and iron-deficiency anaemia is discussed. It was concluded that the most likely cause for the lesions observed is a synergistic relation between infection (weanling diarrhoea, yaws) and metabolic disease (scurvy and possibly hypervitaminosis A). Trauma is not ruled out as contributing to the development of some pathologic lesions. It is concluded that, in the Pacific Islands at least, multiple causes for skeletal pathology in subadults should be considered rather than a single aetiology.