History
Disease emergence
The earliest credible clinical evidence of smallpox is found in the descriptions of smallpox-like disease in medical writings from ancient India (as early as 1500 BCE), and China (1122 BCE), as well as a study of the Egyptian mummy of Ramses V, who died more than 3000 years ago (1145 BCE). It has been speculated that Egyptian traders brought smallpox to India during the 1st millennium BCE, where it remained as an endemic human disease for at least 2000 years. Smallpox was probably introduced into China during the 1st century CE from the southwest, and in the 6th century was carried from China to Japan. In Japan, the epidemic of 735–737 is believed to have killed as much as one-third of the population. At least seven religious deities have been specifically dedicated to smallpox, such as the god Sopona in the Yoruba religion in West Africa. In India, the Hindu goddess of smallpox, Shitala, was worshipped in temples throughout the country.A different viewpoint is that smallpox emerged 1588 CE and the earlier reported cases were incorrectly identified as smallpox.The timing of the arrival of smallpox in Europe and south-western Asia is less clear. Smallpox is not clearly described in either the Old or New Testaments of the Bible or in the literature of the Greeks or Romans.
Livedoid dermatitis is a iatrogenic cutaneous reaction that occurs immediately after a drug injection. It presents as an immediate, extreme pain around the injection site, with overlying skin rapidly becoming erythematous, violaceous, or blanched ("ischemic pallor"): 124  and sometimes with reticular pattern. The reaction eventually leads to variable degrees of necrosis to the skin and underlying tissue. The wound eventually heals, but can lead to atrophic, disfiguring scarring. The reaction is associated with a range of both injection sites and drugs. It was first reported by Freudenthal in 1924 following an injection of bismuth salts for syphilis. Although initial reports were following intramuscular injections, the reaction has since also been reported following subcutaneous, intravenous, and intraarticular injections. Livedoid dermatitis has been reported to occur with many different drug injections, including: penicillins, local anesthetics (e.g. lidocaine), vaccines (e.g. Dtap), corticosteroids, NSAIDs, and more. Presentation
Pathogenesis
The cause of this condition is poorly understood. Microscopic examination of affected tissue shows ischemic necrosis, and so various hypotheses exist to explain this ischemia, including vasospasm from needle prick, the injected drug, or cold compresses applied to the wound. Diagnosis
The diagnosis is mainly clinical. Skin biopsies of the site show necrosis caused by ischemia. Radiographic imaging may help to delineate the extent of the wound. Treatment
Depending on the extent and state of infection of the wound, the condition may require antibiotics, wound debridement in early stages, and corrective plastic surgery in late stages. See also
Injection site reactions
List of cutaneous conditions


== References ==