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Biomedical subjects

Ronni Wolf

Publications and source records attributed to Ronni Wolf.

At least 37 records · Page 2Linked to original sources

The baboon syndrome or intertriginous drug eruption: a report of eleven cases and a second look at its pathomechanism.

Although drug eruptions can mimic a variety of idiopathic skin diseases, this has not been mentioned in the differential diagnosis of intertrigo. We draw attention to an unusual presentation of a drug eruption with a characteristic distribution pattern that is confined to the intertriginous areas. This condition has been given one of the most memorable names in dermatology, the baboon syndrome. Originally, the baboon syndrome was described as a special form of systemic contact-type dermatitis (SCTD) that occurs after ingestion or systemic absorption of a contact allergen in individuals previously sensitized by topical exposure to the same allergen in the same areas. We present eleven cases of intertriginous eruptions that resulted from adverse drug reactions. A flare-up of a previous contact with the same allergen (i.e., drug) on the same areas is not a reasonable explanation for the unusual localization of the eruption in our and others' cases. We believe that we are dealing with a type of recall phenomenon and that the characteristic localization and appearance of the eruption is determined by an earlier, unrelated dermatitis that had occurred in precisely the same areas. Adverse drug reactions should always be considered in the differential diagnosis of intertrigo, especially in atypical and therapy-resistant cases.

Adult↗

Quinine sulfate and HSV replication.

Although antimalarial drugs have been developed primarily to treat malaria, they are also beneficial for many dermatological, immunological, and rheumatological diseases, for which they are mostly used today in the Western world. The aim of the present study was to investigate the effect of quinine sulfate (QS) on the multiplication and adsorption of herpes virus type I (HSV-1). When Vero cells (African green monkey kidney) are infected with HSV-1 in the presence of QS, the viral adsorption is reduced, as demonstrated by a decrease of the number of microscopic plaques of the virus. When the virus-infected Vero cells are incubated in the presence of QS, the multiplication of HSV-1 is also reduced, and the diameter of the plaque are visibly smaller. The practical implications of the antiviral action of antimalarial drugs might be especially important to immunosuppressed patients who receive these drugs for autoimmune collagen-vascular diseases or as additional therapy for AIDS.

Animals↗

Prostaglandin analogs for hair growth: great expectations.

Latanoprost, a prostaglandin analog, has been reported to stimulate eyelash growth in patients using it in eye preparations for glaucoma and body and scalp hair growth when used topically in various animal models. Will prostaglandin analogs be the next agents used for forms of alopecia?

Alopecia↗

Stowaways with wings: two case reports on high-flying insects.

More people than ever before are traversing continents, either for business purposes or on holiday. Because 3-10 percent of these travelers experience skin, hair, or nail disorders related to these trips there is an increasing likelihood that Western physicians will be expected to treat exotic conditions imported from different countries. Tungiasis and furunculoid myiasis are two typical disorders of intertropical regions. They represent nuisances induced by the presence of arthropod larvae or eggs in the skin. We describe a case of tungiasis, caused by the sand flea Tunga penetrans (TP), and a case of myiasis, caused by Dermatobia hominis (DH), and briefly discuss the epidemiology, biologic life cycles, vectors, reservoirs, and clinical presentations of these parasites.

Adult↗

Sunscreens--the ultimate cosmetic.

One decade ago, a sun protection factor (SPF) of 15 was considered a complete blocker of ultraviolet radiation (UV). The logic behind that cutoff point was that sunscreens with this SPF number would always prevent erythema and that preventing erythema would prevent all the ill effects of UV exposure. Today, we know that both of these assumptions were wrong and we tend to recommend higher SPF. Consumers apply only about one-quarter to one-half thickness of the layer of sunscreen material used to measure the SPF in the laboratory. That means that less than 50% of the SPF number claimed on the label is spread on the consumer's skin, meaning that a sunscreen with an SPF 30 will give the real protection of an SPF of 15. Therefore, recommend 60 when you want a real protection of 30! Significant injury, DNA damage, mutations, and carcinogenesis can and do occur also with cumulative suberythemal UV exposure. Thus, erythema induction, a criterion that defines SPF, is not a good indicator of UV damage. We also need higher SPF values to prevent the damage caused by suberythemal doses of UV. The value of the SPF claimed on the label is diminished by environmental factors that are not taken into account during SPF measurements in the laboratory, such as sweating, water immersion, rubbing off, and photodegradation. There are some misunderstandings and confusion about the mode of action of physical sunscreens. It was originally considered that, in contrast to organic sunscreens, the inorganic metal oxides (zinc oxide and titanium dioxide) acted as scatterers or reflectors of UV light, as a mirror. This is not the case with modern micronized forms of metal oxides. It has been shown that both zinc oxide and titanium dioxide mobilize electrons within their atomic structure while absorbing UV radiation. Thus, although metallic oxides are not inert per se, in their coated form they are stable, non-toxic, and safe and they act as highly efficient UV attenuators. Therefore, we recommend our patients to use this type of sunscreens. We should exert all our influence upon our patients not to expose themselves to excessive sunlight, to routinely use generous layers of sunscreen agents, and to wear protective clothing. To wait for the dust to settle around the issue of the effectiveness of sunscreens in preventing melanoma, while the ideal sunscreens--topical, systemic, whatever--are at our disposal, is a luxury we cannot afford.

Cosmetics↗

Still elusive relationship between atopic dermatitis and allergic contact dermatitis.

The relationship between atopic dermatitis (AD) and allergic contact dermatitis (ACD) has long been and continues to be an unsolved and frequently discussed issue. Whereas AD patients have traditionally been considered to have a decreased frequency of ACD, recent studies revealed that these individuals are more or equally likely to develop ACD. The aim of the present review was to determine whether the results of recent experimental studies and theoretical considerations might lead to a parallel shift in our concept on the causal relationship between AD and ACD. It has been shown that Th2 and Th1-type immune responses are not mutually exclusive, and that at least in AD a mixture of both Th2 and Th1 occurs and the interactions between them account for the clinical characteristics of the disease. This new concept on the immunopathomechanism of AD challenges our previous belief that the cytokine pattern of the affected skin is unsuitable for the development of delayed-type hypersensitivity. Since we do not know the exact quantitative balance between Th1 and Th2 reactions along a time axis, we cannot predict whether the cytokine pattern of AD patients favors or inhibits the development of ACD. What we do know with a greater degree of certainty, is that when the eczematous excoriated skin of AD patients, with its defective epidermal barrier (enhancing the penetration of many antigenic substances) is chronically exposed to skin care products and various sensitizing topical medications, it is more likely to develop a superimposed ACD.

Cytokines↗

Cafe au lait has hue of its own.

Segmental pigmentation disorder is a pigmentation disorder (hypo- or hyperpigmentation) first described some 20 years ago. It appears early in life, is segmental, and usually has a sharp border in the midline. It can be confused clinically and histologically with several pigmentary disorders, especially with giant or segmental cafe-au-lait macules. The purpose of this article is to promote, revive, and refresh this somewhat neglected entity, and to further subdivide it into two types: segmental pigmentation disorder simplex and segmental cafe-au-lait. We illustrate our contention with case reports.

Adult↗

Quinine sulfate and bacterial invasion.

BACKGROUND: As many patients who receive antimalarial drugs for treatment of noninfectious, inflammatory diseases are also immunosuppressed and might have a concomitant bacterial infection, we studied the effectiveness of these drugs against bacterial infections, to find out whether they could protect against (and even treat) such conditions and obviate the need for an additional antibiotic drug. METHODS: Effect of QS on bacterial growth: Escherichia coli (E. coli) HB101 pRI203 were cultured overnight at 37 degrees C in TSB and inoculated (approx 1 x 10(7) cells/ml) in MEM in the presence of QS at various concentrations (0, 50 and 100 microM).The effect of QS at concentration of 50 and 100 microM on the entry process of E. coli HB101 pRI203 into HeLa cells was studied under different experimental conditions: 1. QS was incubated with 3 x 10(5) HeLa cells for 60 min at 37 degrees C prior to infection. 2. QS was added to HeLa cell monolayers during the infection period. RESULTS: QS showed no antibacterial activity after 24 h of incubation. The invasive efficiency of the bacteria was significantly inhibited at a dose-dependent manner, when QS was added to HeLa cells for 60 min at 37 degrees C prior to infection (condition 1), and to a lesser extent when added during the period of infection (condition 2). CONCLUSIONS: Although the antimalarials are generally regarded as being inactive against most extracellular bacterial species, our results indicate that QS significantly inhibited the internalization/invasion efficacy of E. coli in the host cells.

Journal Article↗

Comparison of two surgical approaches for treating vitiligo: a preliminary study.

BACKGROUND: Surgical techniques have recently been introduced for patients with vitiligo. Randomized controlled trials have not been performed. AIM: To compare the efficacy and side-effects of two surgical methods (suction blister vs. thin split-thickness graft technique) for the treatment of vitiligo. METHODS: Three suction blisters, approximately 0.8 cm in diameter, made with a special tool attached to a vacuum extractor, which were converted to erosions by removal of the roofs of the bullae, and one round erosion of approximately the same diameter, made using a silver knife, were created. One roof of a blister and two cutaneous thin split-thickness grafts taken from the gluteal region were transferred onto recipient vitiliginous areas; one was left alone. The results were evaluated by one non-blind and two blind observers bimonthly during the 3-month follow-up period. RESULTS: Repigmentation rates were 25-65% in the suction blister technique and 90% in the thin split-thickness graft technique (P < 0.001). CONCLUSIONS: The thin split-thickness graft technique is superior to the suction blister technique in treating vitiligo.

Adolescent↗

Dapsone.

Dapsone (4,4'-diaminodiphenylsulfone, DDS) was synthesized a century ago and continues to be a powerful therapeutic tool in many skin diseases. We have tried to retrieve and present the available knowledge and relevant information on this old but still very useful drug with the hope of encouraging and guiding practicing dermatologists to adapt it for various indications. Our objective is to familiarize the clinician with how this agent works, in what disease states it is effective, how to administer it, what adverse effects may occur, and how to monitor the patient receiving this drug.

Animals↗

Acne and diet.

Forbidden foods? "The first law of dietetics seems to be: If it tastes good, it's bad for you" (Isaac Asimov, Russian-born biochemist and science fiction writer). This was essentially the Magna Carta for dermatologists of the 1950s: anything coveted by the teenage palate was suspect for morning after acne. Today, half a century later, although the slant has shifted away for this line of thinking in our dermatologic textbooks, several articles on the beliefs and perceptions of acne patients showed that nothing much has changed and that they expect us to give them detailed instructions of what "acne-related" foods they should avoid. In one such study(1), diet was the third most frequently implicated factor (after hormones and genetics) as the cause of the disease, with 32% of the respondents selecting diet as the main cause, and 44% thinking that foods aggravate acne. In another study that analyzed knowledge about causes of acne among English teenagers, 11% of the responders blamed greasy food as the main cause of the disease(2), whereas in another study found that 41% of final-year medical students of the University of Melbourne chose diet as an important factor of acne exacerbation on a final examination.(3)

Acne Vulgaris↗

Life-threatening severe allergic reactions: urticaria, angioedema, and anaphylaxis.

Urticaria, angioedema and anaphylaxis are life threatening skin diseases. Allergological emergencies are common; drugs, food, food ingredients/additives, insects, and many other factors have been reported to elicit anaphylactic reactions. The severity of symptoms ranges from pruritus to generalized skin eruptions, gastrointestinal, bronchial problems to systemic anaphylaxis and cardiovascular emergencies. The pathomechanisms and treatment of urticarias, angioedema and anaphylaxis are described. In some situations emergency kit: antihistamines, steroids, betamimetics and adrenaline is needed. Familiarity with the early diagnosis and correct management should be acknowledegable for dermatologists to recognize these allergic reactions and must be prepared to administer emergency kit.

Anaphylaxis↗

Life-threatening acute adverse cutaneous drug reactions.

Adverse cutaneous reactions to drugs are frequent, affecting 2% to 3% of all hospitalized patients. Fortunately, only about 2% of adverse cutaneous reactions are severe and very few are fatal. Stevens-Johnson syndrome and toxic epidermal necrolysis are severe life-threatening diseases with a mortality rate reaching 30%, and only prompt recognition and diagnosis, withdrawal of the offensive drug, and referral to an intensive care unit or burn care unit might improve the prognosis and save the patient's life. Drug eruption with eosinophilia and systemic symptoms syndrome, formerly termed drug hypersensitivity syndrome, is a rather distinct severe adverse drug reaction (ADR) characterized by eruption, fever, lymph node enlargement, and single or multiple organ involvement, with a high morbidity and a mortality rate of 10%. These severe ADRs, together with serum sickness-like syndrome, are discussed in this review. Other severe reactions, such as anaphylaxis and vasculitis, are discussed elsewhere in this issue. Although most of the readers, particularly those in the outpatient arena, will not be treating these patients, they are the ones who will see them first, diagnose them, realize the potential danger in their condition, and refer them to the appropriate treatment venue. Therefore, dermatologists should be familiar with these conditions and be prepared to handle them adequately.

Acute Disease↗

The life-threatening complications of dermatologic therapies.

Dermatologists use a variety of systemic drugs, some of which can cause severe adverse reactions and even fatalities. Ivermectin, a well-tolerated drug, can cause severe neurological side effects, whereas metronidazole, in high cumulative doses, has been associated with convulsions and rarely with hepatotoxicity. Dapsone is associated with frequent hematologic side effects, such as methemoglobinemia, hemolysis, and anemia. Although hepatotoxicity is rare and usually mild and reversible with the new antifungal agents, severe cutaneous reactions (such as toxic epidermal necrolysis, Stevens-Johnson syndrome, and anaphylaxis) have been reported. Even a relatively safe drug such as acyclovir has been reported to be the cause of renal failure and neurotoxicity. Retinoids can cause not so benign "benign" intracranial hypertension. Methotrexate can cause not only liver toxicity, but also myelosuppression and pancytopenia, which may be acute and life threatening. Nephrotoxicity is a well-recognized side effect of cyclosporine, whereas thrombotic thrombocytopenic purpura, which is associated with high morbidity and mortality, is less well known. Dermatologists should be familiar with these and other severe adverse reactions of the most popular and most used systemic medications of our trade.

Anti-Bacterial Agents↗