Staphylococcal toxic epidermal necrolysis (TEN): the expanded mouse model

Staphylococcal scalded skin syndrome in adults. A clinical review illustrated with a new case

Staphylococcal scalded skin syndrome is rarely observed in adults; only 32 cases have been reported. In contrast to infant cases, the mortality rate is high. Two major risk factors have been identified: kidney failure and immunosuppression. In adults, clinical features are similar to those of the typical pediatric disease, but blood cultures are often positive for Staphylococcus aureus. Detection of the exfoliative toxin is required for diagnosis; the newborn mouse bioassay is, therefore, usually performed. New immunologic methods allow precise characterization of the toxins and oligonucleotide probes can be used for rapid detection of toxigenic strains. We report a case of staphylococcal scalded skin syndrome in an immunocompetent adult in whom blood cultures were positive; this is the first case in which both exfoliative toxins A and B have been identified in an adult.

Staphylococcal scalded skin syndrome in a homosexual adult

A homosexual man developed staphylococcal scalded skin syndrome associated with a Staphylococcus aureus septicemia. We discuss the role of prednisone, renal insufficiency, and immunosuppression as predisposing factors to staphylococcal scalded skin syndrome in adults. In particular, our study of the patient's immune function revealed anergy and lymphopenia, with a reduced response to phytohemagglutinin. Studies of T cell subpopulations revealed an elevated percentage of T suppressor cells and a diminished percentage of T helper cells with a depressed T helper/T suppressor ratio. Because of those abnormalities, we suspected acquired immunodeficiency syndrome. A few months after recuperation from the acute disease, the patient has had a normalization of the T helper/T suppressor ratio, but because of persistent polyadenopathy, hypergammaglobulinemia, and a negative sensitization to keyhole-limpet hemocyanin (KLH), we now consider the patient to have an acquired immunodeficiency syndrome-related complex.

Dermal dysplasia, hypotrichosis, and dorsal skin ulcers in adult NMRI-mice after X-irradiation in utero

Prenatal X-irradiation in mice leads to a marked incidence of hypotrichosis and alopecia in offspring, when irradiation occurs during the stage of late organogenesis (day 11-13 p.c.). In addition, severe ulcerative dermatitis occurs in offspring starting at 2 months of age, with marked preference for those animals, which have been irradiated at least during days 11-13 p.c. This occurs without any dose dependence; application of doses between 2.4 Gy and 7.2 Gy results in approximately similar incidence rates of skin ulcers (range between 39.1 and 48.0%). There is no sex preference and no dependence on housing. At autopsy no special abnormalities were found in the internal organs with the exception of frequent signs of amyloidosis. This disease pattern could also be produced in germ-free animals. The intracutanous administration of skin extracts from affected animals into unirradiated mice leads to a marked infiltration of leukocytes. It is therefore suggested that prenatal X-irradiation induces a distinct dysplasia of the epidermis, which is followed by an endogenous leukotactic activity.

Action of staphylococcal epidermolysin: further observations on its species specificity

Sensitivity to epidermolysin was tested in a number of species of the families of mice (muridae) and hamsters (cricetidae) and in hedgehogs. None of the animals proved sensitive except mus musculus (house mouse) and mesocricetus auratus (golden hamster).

The staphylococcal scalded skin syndrome. An experimental histochemical and electron microscopic study

Histochemical and electron microscopic studies were carried out on the newborn mouse model of the staphylococcal scalded skin syndrome to investigate the mechanism of action of the staphylococcal epidermolytic toxin that causes it. Histochemical studies showed that an intra-epidermal split develops below the subcorneal zone which is rich in catabolic enzymes (the so-called esterase-acid phosphatase-rich band). However, histochemical alterations in the enzyme pattern could not be demonstrated. The earliest change revealed by electron microscopy was a widening of the intercellular space, with the formation of microvilli at the level between the stratum spinosum and stratum granulosum where the split later occurs. A clearing of the peripheral cytoplasm along the cell membranes was also revealed. In pre-split areas, adhesion between cell membranes of adjacent cells seems to be lost; desmosomes continue to hold the cells together but the split develops when these are broken by mechanical pressure. Later, damaged cell membranes may be seen. Extracellular keratinosomes remain unchanged. Although these findings do not agree with the already divergent results of other studies, they help support the findings of all groups that cases of the Lyell syndrome produced by staphylococci do not occur through necrolysis; it is therefore inappropriate to continue applying the term 'toxic epidermal necrolysis' to such cases.

The fate of Staphylococcal exfoliatin in newborn and adult mice

The distribution and excretion of the staphylococcal exfoliatin was investigated following in vivo administration of highly purified 125I-labelled exfoliatin fractions to adult and newborn mice. Adult mice excrete approximately one-third of a test dose by 3 hours as compared to a fifteenth of a test dose excreted by newborn mice. Accordingly, blood tracer radioactivity reaches a relatively higher peak and shows a slower decline in newborns than in adults. The urine of adult mice contains considerable biologically active exfoliating material. Both nephrectomized and carbon tetrachloride-poisoned adult mice injected with exfoliatin develop generalized exfoliation whereas comparable doses in untreated controls have no effect. On the other hand, subtotal hepatectomy, followed by injection of exfoliatin, does not lead to exfoliation. We conclude that renal immaturity is a critical factor responsible for the susceptibility of neonates to generalized staphylococcal scalded skin syndrome.