Steroid cream contaminated with Pseudomonas aeruginosa

Microbial contamination and preservative efficacy of topical creams

Nineteen different brands of topical creams were tested in duplicate for microbial growth. The efficacy of their preservation was assessed, when possible, by standard pharmacopoeial procedures. Microbial growth was demonstrated in cultures from all specimens. However, high counts (> 10(4) c.f.u./g) were obtained from eight specimens from six different brands. The microbes were found to belong to different species of bacteria and fungi including Pseudomonas aeruginosa. Two samples of each of the seven, easily emulsifiable creams, were challenged with standard strains of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans to assess the efficacy of the preservatives used in their preparations. With the exception of a single brand, all creams tested were ineffectively preserved. This study highlights the dangers of marketing domestically prepared topical creams and more effective monitoring of the components for all topical creams is recommended. The inclusion of a proper preservative system in these formulas is essential.

Type of closure prevents microbial contamination of cosmetics during consumer use

The dispensing closure used for containers plays an important role in protecting cosmetics from in-use microbial contamination. This hypothesis was tested by aseptically packing unpreserved shampoo and skin lotion into containers with three different closure types which provided various degrees of protection against consumer and environmental microbial insults. Shampoo was packed in containers with slit-cap (n = 25), flip-cap (n = 25), or screw-cap (n = 28) closures. Skin lotion was packed in containers with pump-top (n = 21), flip-cap (n = 18), or screw-cap (n = 21) closures. The products were then used by volunteers under actual in-use conditions for 3 (shampoo) or 2 (skin lotion) weeks. After use, the products were evaluated for microbial contamination by using standard methods for enumeration and identification. The standard screw-cap closure provided only minimal protection against microbial contamination of both the shampoo (29% contamination incidence) and the skin lotion (71%). The slit-cap closure on the shampoo container and the flip-cap closure on the skin lotion container provided slightly enhanced degrees of protection (21 and 39% contamination incidence, respectively). The greatest amount of protection (i.e., lowest contamination incidence) was provided by the flip-cap closure for the shampoo container (0%) and the pump-top closure for the skin lotion container (10%). As a result, closure type plays an important role in protecting poorly preserved products from in-use microbial contamination.

Correlation of in vitro challenge testing with consumer use testing for cosmetic products

An in vitro microbial challenge test has been developed to predict the likelihood of consumer contamination of cosmetic products. The challenge test involved inoculating product at four concentrations (30, 50, 70, and 100%) with microorganisms known to contaminate cosmetics. Elimination of these microorganisms at each concentration was followed over a 28-day period. The test was used to classify products as poorly preserved, marginally preserved, or well preserved. Consumer use testing was then used to determine whether the test predicted the risk of actual consumer contamination. Products classified by the challenge test as poorly preserved returned 46 to 90% contaminated after use. Products classified by the challenge test as well preserved returned with no contamination. Marginally preserved products returned with 0 to 21% of the used units contaminated. As a result, the challenge test described can be accurately used to predict the risk of consumer contamination of cosmetic products.

Toewebs as a source of gram-negative bacilli

The prevalence of Gram-negative bacilli on the toewebs was 8% in normal students, 24% in hospital outpatients with suspected Tinea pedis, 41% in industrial workers wearing protective clothing and 58% in coal miners. Prevalence was greatest in those exposed to wet working conditions. In miners, the presence of Gram-negative bacilli was related to symptoms of itching/soreness and cracking/fissuring, and was negatively related to malodour, but this latter trend was reversed in outpatients and in industrial workers. The feet are a source of many 'enteric' and 'environmental' bacilli and could contribute to infection elsewhere than in the toewebs themselves.

Host factors in whirlpool-associated Pseudomonas aeruginosa skin disease

Pseudomonas aeruginosa folliculitis is the most common recognizable infectious disease occurring after use of whirlpools and hot tubs. The factors that affect the host's susceptibility to whirlpool-related infection are the anatomic and physiologic defenses of normal skin, the microecology of the skin surface, factors intrinsic to the individual host, and behavioral factors. The structural components of the skin maintain an environment at the skin surface that makes human skin an inhospitable habitat for microflora. However, natural and experimental models of P. aeruginosa skin infection suggest that immersion in whirlpools may negate many of the body's normal host defenses, especially the very low humidity at the skin surface. Transient colonization of skin with P. aeruginosa may lead to elaboration of toxins in vivo, resulting in the characteristic dermatitis.

The use and abuse of topical corticosteroids in dermatology

Since their introduction almost 30 years ago, topical corticosteroids have made a dramatic contribution to the management of a wide range of non-infective skin disorders. Their principal mode of action is anti-inflammatory and a variety of potencies and vehicles is available. Several important side effects have been described, of which skin atrophy is the most common, but with careful usage the risks are not great.

Contaminated medicaments in use in a hospital for diseases of the skin

Topical medicaments used by patients with diseases of the skin were examined for microbial contamination. Ps. aeruginosa was isolated from stock pots of a diluted emulsifying ointment used as a soap substitute in the bath. Cross-contamination between patients and medicament was subsequently shown to have occurred.

Microbial contamination of topical medicaments used in the treatment and prevention of pressure sores

Topical medicaments used in the treatment and prevention of pressure sores in patients in three hospitals were examined for Pseudomonas aeruginosa and Staphylococcus aureus contamination. Contamination rates were found to vary between hospitals and were affected by differences in the packaging of the product and in the method of application used by the nursing staff.

Infections in a hospital for patients with diseases of the skin

Studies on infections in a hospital for diseases of the skin are described. Patients were shown to acquire staphylococci in the groin and on the chest at about the same rate as in the nose. In contrast to surgical wards, many staphylococci were resistant to tetracycline but sensitive to penicillin. Nevertheless, much of the epidemic spread of staphylococci was with typical surgical-ward strains rather than with phage group II strains which might be thought typical of skin diseases.

A model for the influence of emulsion formulation on the activity of phenolic preservatives

Basic mathematical models are suggested for calculating the concentration of preservatives which is chemically available in the water of emulsions. It is influenced by the total concentration of preservative in the emulsion, the oil: water partition coefficient of the preservative, the oil: water ratio and the concentration of emulgent. The activity of the preservative is related to the concentration free in the water.

Microbial content of nonsterile therapeutic agents containing natural of seminatural active ingredients

The relationship was investigated between various chemical or pharmaceutical production processes and the extent of microbial contamination, of natural origin, of the resulting products. The products contained active ingredients of vegetable, enzymatic, or animal origin. It was concluded that (i) vegetable products practically free from microbes can be produced if the proper manufacturing steps are taken; (ii) sterilization of the media used to manufacture antibiotics, etc., produces products with little contamination; and (iii) products containing extracts of animal organs require careful refrigeration and addition of preservatives to produce acceptable levels of microbial contamination.