BACKGROUND: Splenic infarction is a rare event in clinical practice, diagnosed by CT scan. There are many causes. They often determine the treatment given. However, there is no consensus on etiological investigations.
METHODS: We present here an almost systematic review of the literature, based on data available on Pubmed from 1991 to 2022. Using the keywords \"splenic infarct\", from 1893 references, 11 cohort studies and 867 clinical cases were included in this review. Articles written in languages using alphabets other than Latin were excluded.
CONCLUSIONS: Analysis of these various studies has enabled us to draw up a list that is intended to be as exhaustive as possible of the causes of splenic infarction. The most frequent are emboligenic heart disease, hematological malignancies, solid neoplasia and certain infections. The descriptions available in the literature were mainly based on isolated clinical cases, not always making it possible to establish a causal link with the disease described, especially as around 20% of reported cases of splenic infarction were asymptomatic and potentially of incidental discovery. Based on the findings of this literature review, we propose a protocol for the etiological assessment of splenic infarcts.

An unprecedented infodemic has been witnessed to create massive damage to human society. However, it was not thoroughly investigated. This systematic review aims to (1) synthesize the existing literature on the causes and impacts of COVID-19 infodemic; (2) summarize the proposed strategies to fight with COVID-19 infodemic; and (3) identify the directions for future research. A systematic literature search following the PRISMA guideline covering 12 scholarly databases was conducted to retrieve various types of peer-reviewed articles that reported causes, impacts, or countermeasures of the infodemic. Empirical studies were assessed for risk of bias using the Mixed-Methods Appraisal Tool. A coding theme was iteratively developed to categorize the causes, impacts, and countermeasures found from the included studies. Social media usage, low level of health/eHealth literacy, and fast publication process and preprint service are identified as the major causes of the infodemic. Besides, the vicious circle of human rumor-spreading behavior and the psychological issues from the public (e.g., anxiety, distress, fear) emerges as the characteristic of the infodemic. Comprehensive lists of countermeasures are summarized from different perspectives, among which risk communication and consumer health information need/seeking are of particular importance. Theoretical and practical implications are discussed and future research directions are suggested.

Background and Objectives: Gut microbiota plays an important role in the wellbeing of the host through different interactions between microflora constituents. In certain instances, Clostridioides difficile may pullulate, causing infection with associated colitis that may vary in terms of severity from mild disease to severe colitis, with increased associated mortality due to its complications. However, there are few literature data regarding the association between Clostridioides difficile and ischemic colitis. Case report: We report the case of a 30-year-old male patient, overweight, with impending dehydration, who presented with hematochezia and colicky abdominal pain, with positive fecal tests for the detection of Clostridioides difficile infection and endoscopic appearance suggesting ischemic colitis in the sigmoid and left colon, confirmed by computed tomography and histology. The patient was treated with oral Vancomycin, with resolution of symptoms, and was reevaluated through colonoscopy eight weeks after discharge, with endoscopic mucosal normalization and histological scarring process on biopsy samples. Conclusion: We report one of the few cases in the literature of ischemic colitis associated with Clostridioides difficile infection, with resolution of clinical, endoscopic, and histologic changes after specific treatment with oral Vancomycin suggesting a possible association between the two diseases. We also review the existing literature data regarding this comorbid association.

OBJECTIVE: Fentanyl poisoning has been widely reported, yet there is a lack of systematic evaluation of the nature and toxicology of associated deaths in the published literature. This article aims to systematically review the nature, causes, routes of administration and toxicology of fentanyl-associated deaths using case studies and case series in peer-reviewed published literature.
METHODS: Four electronic databases including Embase, Medline (via Ovid), Scopus and Google Scholar were searched from inception until October 2019 to identify the studies reporting fentanyl related deaths. Two independent reviewers screened and selected the titles and then evaluated the full texts. Only case studies and case series were included. A structured data extraction tool was used to extract data on the number of deaths, routes of administration, concomitant drug use and toxicological data. The Joanna Briggs Institute quality assessment tool was used to evaluate the quality of included studies. Data were synthesized narratively.
RESULTS: Of 1251 articles identified during initial search, 8 case reports and 9 case series met the inclusion criteria. A total of 1969 deaths were reported in the included studies. Deaths were concentrated in the north American region (n = 1946) and the Nordic region (n = 22). Reported causes of death included fentanyl overdose (n = 321, 56.4%), mixed drug toxicity (n = 196, 34.5%), natural (n = 28, 4.9%), other drug toxicity (n = 10, 1.8%), fentanyl and ethanol intoxication (n = 8, 1.4%), incidental (n = 5, <1%) and aspiration (n = 1). Most common routes of use were intravenous (70.5%) and transdermal routes (23.0%). Deaths came swiftly via the intravenous route. Mean level of blood fentanyl amongst all reported deaths was 0.024 µg/mL.
CONCLUSIONS: Literature related to fentanyl-associated deaths predominantly come from North America. Deaths are comparatively lower or not reported in peer-reviewed publications from the rest of the world. Abuse through intravenous administration, mixed drug toxicities and self-treatment of breakthrough pain are mainly responsible for majority of the reported deaths.

OBJECTIVE: Even 250 years after Beethoven\'s birth, the irrevocable cause of his hearing impairment remains unclear despite multiple publications by different professional groups. This study aimed to analyse the development of the most likely aetiologies during the last 100 years by a systematic review of the relevant medical literature.
METHODS: A systematic review of medical literature in PubMed®, PubMed Central®, and Web of Science® for the period 1920-2020 was conducted. Medical publications between 1920 and 1935 were additionally searched manually by review of reference lists. Studies were eligible when a statement regarding the most likely aetiology of the hearing loss of Beethoven was the aimed objective of the publication.
RESULTS: 48 publications were included. The following aetiologies were supposed: otosclerosis (n = 10), syphilis (n = 9), Paget\'s disease (n = 6), neural deafness (n = 5), immunopathy with inflammatory bowel disease, neural deafness with otosclerosis, sarcoidosis or lead intoxication (n = 2), and systemic lupus erythematosus, trauma, labyrinthitis or inner ear disease (n = 1). There is an ongoing effort with a mean publication frequency in this topic of 0.48/year. From 1920 to 1970, otolaryngologists were the group with the highest interest in this field (67%), whereas since 1971 most authors have belonged to non-otolaryngologic subspecialities (81%).
CONCLUSIONS: Over the past 100 years, otosclerosis and syphilis were predominantly supposed to be the underlying causes. The hypothesis of syphilis-although rejected for a long time-has had a remarkable revival during the past 20 years. Regarding the outcome following therapeutic intervention by cochlear implantation, the differential diagnosis of neural deafness would be relevant today.

BACKGROUND: 10% of patients who undergo a cholecystectomy go on to develop post-cholecystectomy syndrome (PCS). The majority of these patients may suffer from extra-biliary or unrelated organic disorders that may have been present before cholecystectomy. The numerous aetiological causes of PCS result in a wide spectrum of management options, each with varying success in abating symptoms. This systematic review aims to provide a summary of the causative aetiologies of post cholecystectomy syndrome, their incidences and efficacy of available management options.
METHODS: The Medline, Embase and Cochrane databases were searched for studies patients who developed PCS symptoms following laparoscopic cholecystectomy, published between 1990 and 2016. The aetiology, incidence and management options were extracted, with separate collation of randomised control trials and non-randomised studies that reported intervention. Outcomes included recurrent symptoms following intervention, unscheduled primary and secondary care attendances and complications.
RESULTS: Twenty-one studies were included (15 case series, 2 cohort studies, 1 case control, 3 RCTs). Five studies described medical treatment (nifedipine, cisapride, opiates); seven studies described endoscopic or surgical intervention. Early presentation of PCS (<3 years post-cholecystectomy) was more likely to be gastric in origin, and later presentations were found to be more likely due to retained stones. Sphincter of Oddi dysfunction (SOD) accounted for a third of cases in an unselected population with PCS.
CONCLUSIONS: Causes of post cholecystectomy syndrome are varied and many can be attributed to extra-biliary causes, which may be present prior to surgery. Early symptoms may warrant early upper gastrointestinal endoscopy. Delayed presentations are more likely to be associated with retained biliary stones. A large proportion of patients will have no cause identified. Treatment options for this latter group are limited.

Causative factors may be different for the very first onset of symptoms of the \'disease\' of low back pain (LBP) than for ensuing episodes that occur after a pain-free period. This differentiation hinges on a life-time absence of low back pain at first onset and short-term absence for further episodes. In this systematic review, we explored whether researchers make these distinctions when investigating the causality of LBP.
A literature search of PUBMED, CINAHL, and SCOPUS databases was performed from January 2010 until September 2016 using the search terms \'low back pain\' or \'back pain\' and \'risk factor\' or \'caus*\' or \'predict*\' or \'onset\' or \'first-time\' or \'inception\' or \'incidence\'. Two reviewers extracted information on study design, types of episodes of back pain to distinguish the disease of LBP and recurring episodes, and also to determine the definitions of disease- or pain-free periods.
Thirty-three articles purporting to study causes of LBP were included. Upon scrutiny, 31 of the 33 articles were unclear as to what type of causality they were studying, that of the \'disease\' or the episode, or a mere association with LBP. Only 9 studies used a prospective study design. Five studies appeared to investigate the onset of the disease of LBP, however, only one study truly captured the first incidence of LBP, which was the result of sports injury. Six appeared to study episodes but only one clearly related to the concept of episodes. Therefore, among those 11 studies, nine included both first-time LBP and episodes of LBP. Consequently, 22 studies related to the prevalence of LBP, as they probably included a mixture of first-time, recurring and ongoing episodes without distinction.
Recent literature concerning the causality of LBP does not differentiate between the \'disease\' of LBP and its recurring episodes mainly due to a lack of a clear definition of absence of LBP at baseline. Therefore, current research is not capable of providing a valid answer on this topic.

BACKGROUND: Nowadays self-medication is one of the most common public health issues in many countries, as well as in Iran. According to need to epidemiological information about self-medication, the aim of this study was to systematic review and meta-analysis of prevalence and cause of self-medication in community setting of Iran.
METHODS: Required data were collected searching following key words: medication, self-medication, over-the-counter, non-prescription, prevalence, epidemiology, etiology, occurrence and Iran in Google Scholar, PubMed, Scopus, Magiran, SID and IranMedex (from 2000 to 2015). To estimate the overall self-medication prevalence, computer software CMA: 2 applied. In order to report the results, forest plot was employed.
RESULTS: Out of 1256 articles, 25 articles entered to study. The overall prevalence of self-medication based on the random effect model was estimated to be 53% (95% CI, lowest= 42%, highest=67%). The prevalence of self-medication in students was 67% (95% CI, lowest=55%, highest=81%), in the household 36% (95% CI, lowest=17%, highest= 77%) and in the elderly people 68% (95% CI, lowest=54%, highest=84%). The most important cause of self-medication was mild symptoms of disease. The most important group of disease in which patients self-medicated was respiratory diseases and the most important group of medication was analgesics.
CONCLUSIONS: The results show a relatively higher prevalence of self-medication among the Iranian community setting as compared to other countries. Raising public awareness, culture building and control of physicians and pharmacies\' performance can have beneficial effects in reduce of prevalence of self-medication.

BACKGROUND: Back pain is a common condition that starts early in life and seems to increase markedly during puberty. A systematic review was performed in order to investigate the link between puberty and back pain, using some Bradford Hill criteria for causality.
OBJECTIVE: We sought to obtain answers to the following questions: 1) Is there an association between puberty and back pain? If so, how strong is this association? And do the results remain unchanged also when controlling for age and sex? 2) Are the results of the studies consistent? 3) Is there a dose-response, showing a link between the increasing stages of puberty and the subsequent prevalence of back pain? 4) Is there a temporal link between puberty and back pain?
METHODS: A systematic critical literature review.
METHODS: Systematic searches were made in March 2014 in PubMed, Embase, CINAHL and PsycINFO including longitudinal or cross-sectional studies on back pain for subjects <19 years, written in French or English. The review process followed the AMSTAR recommendations. Interpretation was made using some of the Bradford-Hill criteria for causality.
RESULTS: Four articles reporting five studies were included, two of which were longitudinal. 1) Some studies show a weak and others a strong positive association between puberty and back pain, which remains after controlling for age and sex; 2) Results were consistent across the studies; 3) There was a linear increase of back pain according to the stage of puberty 4) Temporality has not been sufficiently studied.
CONCLUSIONS: All our criteria for causality were fulfilled or somewhat fulfilled indicating the possibility of a causal link between puberty and back pain. Future research should focus on specific hypotheses, for example investigating if there could be a hormonal or a biomechanical aspect to the development of back pain at this time of life.

The epidemiology of facial trauma may vary widely across countries (and even within the same country), and is dependent on several cultural and socioeconomic factors. We know of few reviews of published reports that have considered the sex distribution and aetiology of maxillofacial trauma throughout the world. The aim of this review was to discuss these aspects as they have been presented in papers published during the last 30 years. We made a systematic review of papers about the epidemiology of maxillofacial trauma that were published between January 1980 and December 2013 and identified 69 studies from Africa (n=9), North America and Brazil (n=6), Asia (n=36), Europe (n=16), and Oceania (n=2). In all the studies men outnumbered women, the ratio usually being more than 2:1. In American, African, and Asian studies road traffic crashes were the predominant cause. In European studies the aetiology varied, with assaults and road traffic crashes being the most important factors. In Oceania assaults were the most important. A comparison of the incidence of maxillofacial trauma of different countries together with a knowledge of different laws (seat belts for drivers, helmets for motocyclists, speed limits, and protection worn during sports and at work) is crucial to allow for improvement in several countries. To our knowledge this paper is the first attempt to study and compare the aetiologies of maxillofacial trauma.