Sulfur revisited

Nutrition and sulfur

Sulfur is unusual in that it is a mineral that may be taken into the body in both inorganic and organic combinations. It has been available within the environment throughout the development of lifeforms and as such has become integrated into virtually every aspect of biochemical function. It is essential for the nature and maintenance of structure, assists in communication within the organism, is vital as a catalytic assistant in intermediary metabolism and the mechanism of energy flow as well as being involved in internal defense against potentially damaging reactive species and invading foreign chemicals. Recent studies have suggested extended roles for sulfur-containing molecules within living systems. As such, questions have been raised as to whether or not humans are receiving sufficient sulfur within their diet. Sulfur appears to have been the "poor relation" with regards to mineral nutrition. This may be because of difficulties encountered over its multifarious functions, the many chemical guises in which it may be ingested and its complex biochemical interconversions once taken into the body. No established daily requirements have been determined, unlike many minerals, although suggestions have been proposed. Owing to its widespread distribution within dietary components its intake has almost been taken for granted. In the majority of individuals partaking of a balanced diet the supply is deemed adequate, but those opting for specialized or restrictive diets may experience occasional and low-level shortages. In these instances, the careful use of sulfur supplements may be of benefit.

Sulfur for scabies outbreaks in orphanages

Scabies outbreaks occurred in two large orphanages in Chiang Mai, Thailand. Since we were concerned about the availability, safety, and cost of scabicides in Thailand, sulfur in petrolatum was our choice for mass treatment of the children. We studied the efficacy of sulfur in children 2 months to 6 years of age. After the treatment, 47% and 71% of the 102 patients were cured in 2 weeks and 4 weeks, respectively. Only three preschool children developed a mild facial irritation after the first application. This agent is a safe and cheap choice for mass therapy.

Diagnosis and treatment of scabies: a practical guide

Scabies is a common, highly pruritic infestation of the skin caused by Sarcoptes scabiei var. Hominis. It is a very contagious parasitosis with specific lesions, such as burrows, and nonspecific lesions, such as papules, vesicles and excoriations. The typical areas of the body it affects are finger webs, wrists, axillary folds, abdomen, buttocks, inframammary folds and, in men, the genitalia. It is characterized by intense nocturnal pruritus. Scabies is spread through close personal contact (relatives, sexual partners, schoolchildren, chronically ill patients and crowded communities). Definitive diagnosis is made when the scabies mites or their eggs or fecal pellets can be identified on a light microscope. New techniques for diagnosis include the use of the epiluminiscence microscopy. The most common topical treatments for scabies include lindane and permethrin. Permethrin provides a greater margin of tolerability because of its low inherent toxicity and low percutaneous absorption. Oral ivermectin is the most recently developed treatment for scabies. A single oral dose of ivermectin 200 microg/kg of bodyweight is a well-tolerated and very effective treatment. It is especially indicated in crusted scabies, scabies in immunocompromised hosts and infestations in crowded communities. It is also useful as a simple treatment in the prophylaxis of close contacts.

Pharmacotherapy of ectoparasitic infections

Epizoonoses such as scabies, lice and cimicosis are common, vexing disorders that occur worldwide. Historically, many treatment modalities have been employed in the management of these disorders, and most of the drugs described in this review are of historical interest and no longer recommended or in widespread use because of their wide spectrum of adverse effects. More recently, reports documenting resistance against various antiectoparasite drugs, complicated and severe courses of the diseases, and adverse effects of drug therapy have prompted the development of new treatment strategies and drugs for optimal disease management. Because the strategies currently recommended for the treatment of ectoparasites differ worldwide, this review proposes a rational approach to selecting the best therapeutic agent by comparing the pharmacokinetics, pharmacodynamics, drug efficacy and adverse effects. A literature search of the currently Internet accessible libraries PubMed, Medline and Ideal library, of citations of articles found there, and from communications with the Federal Institute for Drugs and Medical Devices, Germany, was conducted based on this approach. One major observation of this literature search is that permethrin is the treatment of choice for lice and scabies in the US and in Great Britain, whereas lindane is still recommended for scabies in most other European countries because of its longer-standing record of effectiveness. Although permethrin has not yet been proven to be more effective than lindane in treating infections with these ectoparasites, it currently appears to have the best efficacy versus safety profile of topical treatments for scabies and lice. Ivermectin is a newer oral drug for the treatment of ectoparasites, which has been used with great success in the treatment of onchocercosis and other endoparasites. Although ivermectin appears to be a promising drug, its role in the treatment of ectoparasitic infections will be clarified as more study data become available. Finally, it is important to emphasise the clinical aspects of ectoparasite therapy and that providing the patient with optimal instructions on the use of topical therapeutics is of great importance in avoiding adverse effects and assuring complete removal of the ectoparasite, thereby avoiding the development of drug-resistance.

A risk-benefit assessment of agents used in the treatment of scabies

Permethrin is probably the most effective topical treatment for scabies. There is little microbial resistance to the drug, and it is highly effective. Toxicity is limited to occasional contact dermatitis. Similarly, oral ivermectin 200 micrograms/kg is extremely effective. Oral administration eliminates the need to be certain that medication has been applied properly. Toxicity has been very limited. It is not available in the US for human use in scabies at this time. The toxicity of most of other treatments that are available has not been studied carefully. Sulphur 6% in petrolatum is recommended as safe, but there are no good studies to confirm this. Sulphur is probably the medication of choice when cost is the overriding concern. Crotamiton and benzyl benzoate are probably safe, but are not as effective as permethrin. Lindane has some potential CNS toxicity if used incorrectly, and must be used carefully on damaged skin to avoid excessive absorption. It is important to stress that all household and sexual contacts must be treated, whether or not they have symptoms. Proper application of topical medications must be achieved, including under the fingernails, and up to the edge of all body orifices.

Neonatal scabies treated with permethrin 5% cream

Scabies in neonates and infants has a clinical pattern that may be easily misdiagnosed. The eruption is generalized, including involvement of the head, neck, face, palms, and soles, with an early tendency to pustule formation. Other lesions include papules, vesicles, and burrows, which may be obliterated by secondary lesions. A confusing clinical picture resulted in a delay in diagnosing scabies in a 23-day-old infant who was successfully treated with permethrin 5% cream.

Therapeutic efficacy, secondary effects, and patient acceptability of 10% sulfur in either pork fat or cold cream for the treatment of scabies

Twenty-six children with scabies and 32 contacts were treated with 10% sulfur in cold cream. A 100% clinical cure rate was observed, although 56.8% of patients experienced some kind of mild, transient cutaneous reaction. An additional 25 children with scabies and 28 contacts were treated with 10% sulfur and 1% salicylic acid in pork fat. Of these, 88% were clinically cured and 73.5% had some cutaneous adverse effects. In both groups, most adverse effects were related to skin dryness or postscabetic reaction. The cold cream base was more acceptable to patients than the pork fat base. However, the pork fat base was significantly cheaper and easier to obtain than the cold cream base, and 238 times less expensive than the cheapest commercial scabicidal medication available in the United States.