Most come from only four phyla: Actinomycetota (51.8%), Bacillota (24.4%), Pseudomonadota (16.5%), and Bacteroidota (6.3%). Propionibacteria and Staphylococci species were the main species in sebaceous areas. There are three main ecological areas: moist, dry and sebaceous. In moist places on the body Corynebacteria together with Staphylococci dominate. In dry areas, there is a mixture of species but dominated by Betaproteobacteria and Flavobacteriales. Ecologically, sebaceous areas had greater species richness than moist and dry ones. The areas with least similarity between people in species were the spaces between fingers, the spaces between toes, axillae, and umbilical cord stump. Most similarly were beside the nostril, nares (inside
the nostril), and on the back. Reflecting upon the diversity of the human skin researchers on the human skin microbiome have observed: "hairy, moist underarms lie a short distance from smooth dry forearms, but these two niches are likely as ecologically dissimilar as rainforests are to deserts. "The NIH conducted the Human Microbiome Project to characterize the human microbiota which includes that on the skin and the role of this microbiome in health and disease.Microorganisms like Staphylococcus epidermidis colonize the skin surface. The density of skin flora depends on region of the skin. The disinfected skin surface gets recolonized from bacteria residing in the deeper areas of the hair follicle, gut and urogenital openings. Clinical significance
Diseases of the skin include skin infections and skin neoplasms (including skin cancer).
Ethionamide is an antibiotic used to treat tuberculosis. Specifically it is used, along with other antituberculosis medications, to treat active multidrug-resistant tuberculosis. It is no longer recommended for leprosy. It is taken by mouth.Ethionamide has a high rate of side effects. Common side effects include nausea, diarrhea, abdominal pain, and loss of appetite. Serious side effects may include liver inflammation and depression. It should not be used in people with significant liver problems. Use in pregnancy is not recommended as safety is unclear. Ethionamide is in the thioamides family of medications. It is believed to work by interfering with the use of mycolic acid.Ethionamide was discovered in 1956 and approved for medical use in the United States in 1965. It is on the World Health Organizations List of Essential Medicines. Medical uses
Ethionamide is used in combination with other antituberculosis agents as part of a second-line regimen for active tuberculosis.Ethionamide is well absorbed orally with or without food, but is often administered with food to improve tolerance. It crosses the blood brain barrier to achieve concentrations in the cerebral-spinal fluid equivalent to plasma.The antimicrobial spectrum of ethionamide includes M. tuberculosis, M. bovis and M. segmatis. It also is used rarely against infections with M. leprae and other nontuberculous mycobacteria such as M. avium and M. kansasii. While working in a similar manner to isoniazid, cross resistance is only seen in 13% of strains, since they are both prodrugs but activated by different pathways.