Bibliometric analysis of literature on toxic epidermal necrolysis and Stevens-Johnson syndrome: 1940 – 2015

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are uncommon, but serious and sometimes fatal adverse skin and mucous reactions [1]. Stevens and Johnson were the first to describe SJS in 1922 while Lyell was the first to describe TEN in 1956 [2, 3]. Up until early 1990s, erythema multiforme major (EMM) and SJS were considered similar clinical conditions. However, in 1993 EMM and SJS were identified as two distinct disorders [4]. TEN and SJS are now considered part of a continuum with SJS representing the less severe form of the reaction, and TEN representing the more severe end. The TEN involves larger total body surface area than SJS. The “SJS/TEN” is considered an intermediate form [5‐7]. Incidence rates of TEN and SJS varies across the studies but it is generally less than two cases per million each year [7]. The reported mortality in patients with SJS varies from 3 to 10% while those with TEN have higher mortality rate and ranges from 20 to 40% [8]. The medical outcome of SJS and TEN varies depending on the medical condition of the patient when initiating therapy of the condition [9].

Both SJS and TEN are most often triggered by certain medications, most commonly anticonvulsants, non-steroidal anti-inflammatory drugs, and antibiotics [10, 11]. Unfortunately, a recent study showed that there is an under reporting of drug – induced SJS and TEN [12]. Common over-the-counter drugs such as paracetamol and ibuprofen have been reported in some cases of SJS and TEN [13]. According to Stevens Johnson Syndrome foundation (SJSF), any medication, including cocaine and Ginseng containing herbal products, can cause SJS and TEN [14]. Other causes of SJS and TEN include certain infections [15]. For unclear reasons, it was found that patients with human immune deficiency virus (HIV) have higher risk of developing SJS and TEN compared to un-infected people [7, 16‐21]. Other infections such as Mycoplasma pneumoniae infections and herpes simplex viral infections were linked to SJS and TEN even without previous exposure to medications [22‐27]. SJS and TEN are associated with certain HLA types [28‐32]. The genetic basis of SJS and TEN might be responsible for variations in reporting of drug-induced SJS and TEN in different parts of the world [33]. Better understanding of these variation can help in developing preventive and therapeutic policies for SJS and TEN [34].

Being considered rare conditions, studies on SJS and TEN are required. Such studies are beneficial for pharmacologists, clinical toxicologists, and clinicians in various medical specialties such as dermatologists, pediatricians, and critical care specialists. One method to enrich literature about a certain topic is to provide detailed analysis of published literature on that particular topic. Such analysis of literature is called bibliometric analysis. Therefore, this study was carried out to give a bibliometric overview of literature on TEN and SJS. Bibliometric analysis is not intended to be a review article of scientific information on TEN and SJS, rather an analysis of published literature in terms of annual growth, productivity of various countries, institutions and authors, international collaboration, highly cited articles, and to lesser extent discussion of the content of highly cited articles. Bibliometric analysis on various medical subjects, including new subjects such as telemedicine have been carried out and published [35‐44]. Such studies added new information to the scientific literature of these conditions and added momentum to research aspects of these conditions. Rare diseases and conditions should be given priority in bibliometric studies to establish baseline data for future comparison. Therefore, we believe that such a study will be a positive addition to the field of rare diseases in general and to SJS and TEN in particular.