bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple Concussions and Retirement from Sport
Authors: Hainline Brian , Gurin Lindsey J. , Torres Daniel M.
Published: February 2020

Retirement from sport is a big decision for any athlete. Currently there are no evidence- or consensus-based guidelines for retirement from sport following multiple concussions. This gap is compounded by the lack of objective biomarkers to guide such decision-making. Current recommendations for retirement center around worrisome neurological findings on exam or brain imaging, prolonged recovery following concussion, low threshold for developing concussion, and shortened time intervals between concussions. Retirement from sport following one (or multiple) concussions should be based on multiple factors, including evidence of neurologic impairment, prolonged recovery, lower threshold for developing concussion, and personal/family concerns.
Repetitive Head Impact Exposure
Authors: Hainline Brian , Gurin Lindsey J. , Torres Daniel M.
Published: February 2020

Repetitive head impact exposure refers to a head impact that does not lead to the clinical manifestation of concussion. There is emerging information that repetitive head impact exposure may lead to structural changes in the brain, but it is not clear if these changes normalize, remain static, or worsen over time. Currently there is no known causal connection between repetitive head impact exposure and long-term neurologic diseases, although such a connection is often assumed by the public. A safety-first approach should always be taken in sport, and this includes steps to mitigate head impact exposure.
Unmasking Neuropsychiatric Disorders Following Concussion
Authors: Hainline Brian , Gurin Lindsey J. , Torres Daniel M.
Published: February 2020

Sometimes concussion is accompanied by an abrupt change in behavior, including psychosis or dementia, but concussion is not necessarily the cause. It is more likely that head injury can sometimes unmask an underlying predisposition to another neuropsychiatric disease that has already begun to manifest, often sub-clinically. Such unmasking may occur as a result of a brain injury superimposed on an already vulnerable brain, or a brain injury that contextually removes the individual from a routine that served as a reliable and dependable structural context. Thus, when abrupt neuropsychiatric manifestations such as psychosis or dementia manifest after concussion, a thorough neuropsychiatric evaluation should be performed, and one should not simply assume that concussion is the cause.
On being a patient
Authors: Booth Christopher
Published: February 2020

Those who practise medicine should remember that we are all patients at some time, most likely at the beginning and end of our lives. Therefore, this textbook begins with an account of encounters with the medical and nursing professions, written by an outstanding doctor, medical historian, and leading clinical scientist. After a highly distinguished and eventful career which spanned the introduction of the British National Health Service in 1948, Christopher Booth died in 2012, aged 87 years. Latterly, he experienced the protracted misery of illness punctuated by repeated surgery; but to the end he retained his intellect and penetrating wit. His piquant observations are a challenge to us all as we try to provide care for our patients, as is his parting shot: ‘If you are a physician, no matter how important you may think that you are, you should, so far as your own illnesses are concerned, consider yourself a layman.’
Evolution: Medicine’s most basic science
Authors: Nesse Randolph M. , Dawkins Richard
Published: February 2020

The role of evolutionary biology as a basic science for medicine is expanding rapidly. Some evolutionary methods are already widely applied in medicine, such as population genetics and methods for analysing phylogenetic trees. Newer applications come from seeking evolutionary as well as proximate explanations for disease. Traditional medical research is restricted to proximate studies of the body’s mechanism, but separate evolutionary explanations are needed for why natural selection has left many aspects of the body vulnerable to disease. There are six main possibilities: mismatch, infection, constraints, trade-offs, reproduction at the cost of health, and adaptive defences. Like other basic sciences, evolutionary biology has limited direct clinical implications, but it provides essential research methods, encourages asking new questions that foster a deeper understanding of disease, and provides a framework that organizes the facts of medicine.
Biological therapies for immune, inflammatory, and allergic diseases
Authors: Isaacs John D. , Thalayasingam Nishanthi
Published: February 2020

Therapeutic monoclonal antibodies and related molecules are increasingly used to treat immune-mediated and inflammatory diseases. They interact very precisely with a soluble or cell-bound ligand to have three predominant effects: neutralization of proinflammatory cytokines or growth factors; modulation of intercellular interactions; or depletion of pathogenic cells. They deliver significantly enhanced specificity in comparison to traditional synthetic drugs and have delivered substantial improvements in clinical outcomes in many immune, inflammatory, and allergic diseases. However, there are no biomarkers to help decide which biological class to try first in a particular patient, hence one of the main challenges for the future is the identification of ‘stratifiers’ to guide therapy.
Traditional medicine exemplified by traditional Chinese medicine
Authors: Liao Fulong , Jiang Tingliang , Tu Youyou
Published: February 2020

Traditional (often synonymous with complementary) medicine can be defined as the knowledge, skill, and practices, based on the theories, beliefs, and experiences indigenous to different cultures, which are used in the maintenance of health and the prevention, diagnosis, improvement, or treatment of illness. These practices are found in almost every country, and demand for them is increasing. For individual patients, when of proven quality, safety, and efficacy, traditional medicine contributes to the goal of ensuring that all people have access to care that they feel they need. For medical science, investigators in traditional fields have discovered new medicines with which to combat important diseases, including the sympathomimetic ephedrine, the antimalarial artemisinin, and arsenic trioxide used in the treatment of promyelocytic leukaemia.
Research in the developed world (a view from the Wellcome Trust)
Authors: Farrar Jeremy
Published: February 2020

The entire health system seeks to prevent disease, or diagnose and intervene effectively to limit its impact. The goal of most funders of medically related research in the developed world is to support research that is upstream of that which is relevant and attractive to health providers or pharmaceutical companies, and to work synergistically in the health research ecosystem with these and other complementary organizations when appropriate. It is often impossible to predict which advances in basic science will lead to breakthroughs, but if this upstream work is not done, then in the mid and long term, the flow of medical advances will dry up.
Cytokines
Authors: McInnes Iain B.
Published: February 2020

74Cytokines are small glycoprotein mediators that are involved in every facet of immune effector function and regulation, and moreover serve to integrate immune function with other physiologic processes (e.g. metabolism, neurologic function). More than 200 cytokines have been identified. Understanding of the cytokine network has increasing importance in clinical practice with the advent of therapeutic strategies that target particular cytokines with exquisite specificity using biological agents, leading to remarkable advances in the treatment of inflammatory disorders (e.g. anti-TNF therapy in rheumatoid arthritis and anti-IL-17A in psoriasis). The therapeutic potential in their manipulation has not yet been maximized and the future will hold remarkable advances as these molecular networks give up their secrets to provide for highly specific and well-tolerated interventions.
The complement system
Authors: Botto Marina , Pickering Matthew C.
Published: February 2020

The complement system, consisting of soluble and membrane-bound proteins, is a major effector mechanism of host defence against infection and inflammatory responses. It has an important role in the removal of immune complexes and dying cells, and also modulates humoral and cell-mediated immune responses. Complement activation occurs through three pathways, each generating enzyme complexes, termed C3 convertases. These cleave native C3 to form C3b and C3a. C3b can covalently attach to surfaces (e.g. pathogen surfaces) where it triggers biological responses following interaction with membrane-bound receptors and can also trigger cleavage of native C5 to C5b and C5a. C5b triggers the formation of the membrane attack complex, which disrupts target cell membrane integrity and may result in cell lysis.
Clinical features and management
Authors: Eisen Tim , Gore Martin
Published: February 2020

Cancer comprises many varying conditions, with very different requirements for the basic elements of a population-based cancer care service. The biggest change in the delivery of cancer management in the last 20 years has been the recognition that cancer management is a multiprofessional and multidisciplinary effort. There is a hierarchy of aims for cancer treatment which stretch from cure to palliation. Four key measures to reduce the burden of cancer on the patient, their family, and on the healthcare system are: (1) early diagnosis to maximize the chances of cure and minimize the morbidity of treatment; (2) access to best treatment irrespective of chronological age or home address of the patient; (3) increased physical activity; and (4) a ‘recovery package’ of care and support.
Older people in hospital
Authors: Ellis Graham , MacLullich Alasdair , Harwood Rowan
Published: February 2020

Older people usually present to hospital because of a crisis: a sudden change in health, function, or circumstances that causes worry, distress, or overwhelms independence or care provision. Crises may relate to the individual, the carer, care systems, or the environment. At the point of presentation it may not be clear which, or what combination, of these is responsible. It is necessary to identify all relevant factors for hospital care to be effective and efficient. Admission to hospital for an acute illness can have a major negative impact on an older person’s ongoing functional abilities, hence systems of care need to know when to expect and how to manage functional deterioration.
Drugs and prescribing in the older patient
Authors: Witham Miles , George Jacob , O’Mahony Denis
Published: February 2020

The use of pharmacological agents is often a central component of medical therapy for older people. Medications can relieve symptoms, improve function, and prevent illness, but they also have the capacity to inflict great harm. Older people are at particular risk of such harms as a result of impaired homeostatic reserve, of altered drug metabolism, the presence of multimorbidity and consequent polypharmacy, which increases both exposure to potentially harmful agents and the chance of drug–drug interactions. The therapeutic priorities for older, frail people may differ when compared to younger, robust patients; limited life expectancy means that attempts to prolong life may become relatively less important than the relief of symptoms and avoidance of side effects and medication burden.
Bladder and bowels
Authors: Orme Susie , Harari Danielle
Published: February 2020

Urinary incontinence is not an inevitable consequence of ageing and its impact on social, psychological, and physical well-being is comparable to that of other chronic conditions such as diabetes and dementia. Meanwhile, constipation, including symptoms of evacuation difficulty and/or fewer bowel movements, is a common problem as people age. Risk factors include problems in cognition, mobility, gastrointestinal motility, dysautonomia, anorectal dysfunction, and disabling neurologic disorders. Faecal incontinence is more common in frail individuals but is often assessed inadequately. The cause is often multifactorial. Treatment depends on the cause: a combination of approaches may be necessary, including avoidance of faecal impaction, instigation of a structured bowel care plan including regular prompted toileting, dietary modification, and (in some cases) use of loperamide or similar medications.
Fever of unknown origin
Authors: Vanderschueren Steven
Published: February 2020

Fever of unknown origin refers to a prolonged febrile illness that persists without diagnosis after careful initial assessment. Although over 200 causes have been described, including rare diseases, most cases are due to familiar entities presenting in an atypical fashion. The ‘big three’ are infections, tumours, and multisystem inflammatory conditions. A miscellaneous category including factitious fever, habitual hyperthermia, and drug fever deserves consideration early in a patient’s workup, since timely recognition may avert invasive and expensive procedures. The clinician must rely on a very careful and thorough clinical history and examination that does not neglect any part of the body, followed by appropriately targeted investigations directed by knowledge of the broad spectrum of diseases and local epidemiology.
Travel and expedition medicine
Authors: Dunachie Susanna , Conlon Christopher P.
Published: February 2020

Tourists, business people, pilgrims, and visitors to friends and relatives are making increasing numbers of trips to tropical and developing parts of the world, where the risk and range of infectious and environmental diseases and injuries may be much higher than in Western countries. The aim of travel and expedition medicine is to reduce risk through education, appropriate immunizations, and other medical advice, hence enhancing the enjoyment and achievements of travelling abroad. Explorers, expeditioners, and wilderness travellers face the greatest health challenges, but risk can be minimized by technical competence, careful planning, training in practical medical skills, and rehearsing emergency evacuation.
Epstein–Barr virus
Authors: Rickinson Alan B. , Epstein M.A.
Published: February 2020

Epstein–Barr virus is a human herpesvirus with a linear double-stranded DNA genome that is carried asymptomatically by most people. Symptomless primary infection is usual in childhood, establishing a lifelong carrier state where the virus persists as a latent infection of circulating B cells. The virus replicates recurrently in oropharyngeal epithelial cells, with consequent shedding of virus in saliva transmitting infection. Controversially, Epstein–Barr virus has been linked with certain autoimmune diseases. In particular, there is strong serologic and epidemiologic evidence to suggest that previous exposure to Epstein–Barr virus markedly increases the risk of developing multiple sclerosis. Although the Epstein–Barr virus/multiple sclerosis connection is receiving much attention, the mechanism that might underpin such an association remains uncertain.
Nipah and Hendra virus encephalitides
Authors: Tan C.T.
Published: February 2020

Nipah and Hendra are two related viruses of the Paramyxoviridae family that have their reservoir in large Pteropus fruit bats. Both viruses are two new zoonotic viruses that have emerged in recent years. Both are of the Paramyxoviridae family, sharing many similar characteristics. Because of their homology, a new genus called Henipavirus (Hendra + Nipah) was created for these two viruses. Human disease manifests most often as acute encephalitis, which can be late-onset or relapsing, or pneumonia, with high mortality. Transmission from bats to human includes direct spread from consumption of food contaminated by infected bat secretions, and contact with infected animals; human-to-human spread can also occur.
Alphaviruses
Authors: Powers Ann M. , Ooi E.E. , Petersen L.R. , Gubler D.J.
Published: February 2020

There are 31 registered alphaviruses belonging to the family Togaviridae, 16 of which are known to cause human infection. They are RNA viruses with global geographical distribution and complex transmission cycles, usually between wild or domestic animals and one or more mosquito species; humans are infected by mosquito bites and are often incidental hosts that do not contribute to the maintenance of the virus. They cause a spectrum of clinical manifestations ranging from non-specific febrile illness to chronic arthralgia to acute encephalitis and death. Diagnosis of infection is made by several methods including serologically by detection of IgM and/or IgG antibodies, virus isolation, molecularly using reverse transcription–polymerase chain reaction, or by immunohistochemistry on tissue samples.
Papillomaviruses and polyomaviruses
Authors: Viscidi Raphael P. , Tan Chen Sabrina , Fakhry Carole
Published: February 2020

There are nearly 200 human papillomavirus types that infect epithelia of skin and mucous membranes. They infect only humans, and cause conditions including the following:

skin warts and verrucas, which are caused by types 1 and 2; infection initiated when, after minor skin abrasions, for example, the basal cells of the epithelium come in contact with infectious virus;

anogenital warts, which are caused by types 6 and 11; transmitted by direct sexual contact, these are the most common sexually transmitted infection; present clinically as multiple exophytic lesions or as subclinical flat lesions. They can be treated topically with podophyllin or imiquimod, or by ablative surgical methods. Recurrences are common. A highly efficacious prophylactic vaccine is available.
Molluscum contagiosum
Authors: Warrell David A. , Conlon Christopher P.
Published: February 2020

Molluscum contagiosum is caused by a Molluscipox DNA virus which infects keratinocytes of the epidermal stratum spinosum, producing distinctive small umbilicated papules on the skin. Its genome encodes a variety of proteins that suppress the host’s immune response. In children it is spread by skin contact, producing few or many lesions, while in sexually active adults it causes anogenital lesions. Molluscum is self-limiting within a few years in the immunocompetent, but those with pre-existing atopic eczema and immunosuppression, notably AIDS, commonly develop persistent diffuse eruptions with larger papules. Lesions can be removed mechanically or chemically. More severe infections can be treated with imiquimod or cidofovir.
Pseudomonas aeruginosa
Authors: Koh G.C.K.W. , Peacock Sharon J.
Published: February 2020

Pseudomonas aeruginosa is a highly versatile environmental Gram-negative bacterium that can be isolated from a wide range of habitats, including soil, marshes, and the ocean, as well as from plant and animal tissues. It is resistant to many disinfectants and antibiotics, giving it a selective advantage in hospitals. It rarely causes infection in the healthy host but is a major opportunistic pathogen. Diagnosis is usually straightforward when the organism is cultured from samples collected from normally sterile sites, but is often challenging when infection is suspected in non-sterile sites such as a catheterized urinary tract, burns, or skin ulcers, because P. aeruginosa may be either a pathogen or an innocent bystander. Treatment can be challenging as P. aeruginosa is intrinsically resistant to a broad range of antimicrobials.
Intracellular klebsiella infections (donovanosis and rhinoscleroma)
Authors: Richens John , Stoesser Nicole
Published: February 2020

Two rare intracellular species of Klebsiella, a Gram-negative bacillus, cause granulomatous disease in humans that is found in small endemic foci in warm climates, linked to poverty and poor hygiene. Donovanosis is caused by Klebsiella granulomatis (previously named Calymmatobacterium granulomatis) and is presumed to be sexually transmitted. Presenting with genital ulcers or growths, often accompanied by an inguinal ‘pseudobubo’ (granuloma inguinale), it is diagnosed by demonstrating Donovan bodies (vacuoles containing capsulated coccoid bacteria) lying within histiocytes in material taken from a typical lesion. Treatment is with azithromycin; surgery may be needed for complications. Rhinoscleroma, caused by Klebsiella rhinoscleromatis, is believed to transfer from person to person; following a period of rhinitis it most typically manifests with bulky growths in the upper respiratory tract. It is diagnosed by demonstrating intracellular organisms in typical lesions, combined with culture. Treatment is with ciprofloxacin; surgical debulking of lesions and/or reconstruction may be required.
Cystoisosporiasis
Authors: Weiss Louis M.
Published: February 2020

Cystoisospora belli is a coccidian protozoan that colonizes epithelial cells of the small intestine. Infection occurs by ingestion of parasite oocysts in water or food. Clinical features of infection include watery diarrhoea, dehydration, fever, and weight loss in both immune competent and immune deficient patients. Cystoisospora belli forms tissue cysts that allow for relapses of this infection. Cystoisosporiasis presenting as chronic diarrhoea is an opportunistic infection associated with HIV infection. Diagnosis is by microscopic examination of faecal specimens for C. belli oocysts, which show blue autofluorescence under ultraviolet light. Cystoisospora belli infection, even in patients with AIDS, responds rapidly to treatment with co-trimoxazole.
Blastocystis infection
Authors: Knight Richard
Published: February 2020

Blastocystis is an anaerobic unicellular non-invasive colonic parasite of animals and humans. It is transmitted faeco-orally, with human infection associated with travel, institutions, animal handlers, and immunodeficiency. Case reports strongly suggest that it causes a self-limited diarrhoeal illness. Diagnosis is by microscopic examination of faecal smears or concentrates. A trial of treatment with metronidazole is justified in patients who are immunocompromised, also when symptoms are prolonged. Molecular and ribosomal RNA studies now indicate that Blastocystis is a Stramenopile (a synonym for kingdom Chromista), currently only one species is recognized. Blastocystis has no flagellae, unlike other stramenopiles, which include slime nets, water moulds, and brown algae.
Chagas disease
Authors: Miles Michael A.
Published: February 2020

Trypanosoma cruzi, the protozoan parasite that causes Chagas disease, is a zoonotic infection with many mammal host and vector species. It is transmitted to humans by contamination of mucous membranes or abraded skin with infected faeces of bloodsucking triatomine bugs, also by blood transfusion, organ transplantation, transplacentally, and orally by food contaminated with infective forms. It multiplies intracellularly (pseudocysts) as amastigotes in mammalian cells, particularly heart and smooth muscle, from which flagellated trypomastigotes emerge to reinvade cells or circulate in blood. Around 10 million people are infected in Latin America; imported cases and congenital cases may occur elsewhere. Proven methods of controlling domestic triatomine bugs include insecticide spraying (with pyrethroids), health education, community support, and house improvement. Serological surveillance of children detects residual endemic foci or congenital transmission and is vital for monitoring the success of control programmes. There is no vaccine.
Trichomoniasis
Authors: Schwebke Jane
Published: February 2020

Trichomonas vaginalis is a sexually transmitted protozoan pathogen that may cause more than one-half of all curable sexually transmitted genital infections worldwide. Women with trichomoniasis are often asymptomatic, but they may develop vaginal malodour, discharge, erythema, or itching, and their male or female sexual partners may also be infected, although urethritis in men is less likely to cause symptoms. Women with trichomoniasis have an increased risk of HIV acquisition, HIV shedding, pelvic inflammatory disease, and preterm birth. For diagnosis, rapid antigen detection, culture, and polymerase chain reaction methods have advantages over conventional microscopy, but are more expensive. Oral metronidazole is usually an effective treatment, with both sexual partners needing to be treated to prevent reinfection.
Gut and tissue nematode infections acquired by ingestion
Authors: Chiodini Peter L.
Published: February 2020

Ascaris lumbricoides (the human roundworm) is widespread in the tropics and subtropics where sanitation is poor and the soil is contaminated with its eggs. Ascaris suum (the pig roundworm) is also capable of infecting humans. Some authorities consider them to be the same species, making A. suum a synonym of A. lumbricoides. Ingested eggs hatch in the small bowel, the larvae released migrate via the bloodstream and lungs, then return to the small bowel and develop into adult worms 15–30 cm long. Most infections are asymptomatic, but there may be pulmonary infiltrates with eosinophilia, abdominal discomfort and—in children with heavy infections—intestinal obstruction. Infection is diagnosed by finding eggs in the faeces. Treatment is with mebendazole, albendazole, or pyrantel pamoate.
Cystic hydatid disease (Echinococcus granulosus)
Authors: Moro Pedro L. , Garcia Hector H. , Gonzalez Armando E.
Published: February 2020

Cystic hydatid disease, caused by Echinococcus granulosus, is a zoonotic disease principally transmitted between dogs and domestic livestock, particularly sheep. Humans are infected when they ingest tapeworm eggs, with disease occurring in most parts of the world where sheep are raised and dogs are used to herd livestock. The most common clinical manifestations are cysts in the liver (typically presenting with hepatomegaly) and/or lung (presenting with cough, haemoptysis, and dyspnoea). Diagnosis is usually made on the basis of serological tests in combination with imaging techniques. Treatment options include surgery, chemotherapy with anthelminthic agents, or—for liver cysts—PAIR (puncture–aspiration–injection–reaspiration). Echinococcosis is a major public health problem in several countries. Control programmes have been aimed at educating dog owners to prevent their animals from having access to infected offal. Vaccines against sheep hydatidosis and the dog tapeworm stage are promising alternatives.
Sexual history and examination
Authors: Brook Gary , Sherrard Jackie , Luzzi Graz A.
Published: February 2020

Sexually transmitted infections (STIs) are common, especially in young people, and it is important that doctors recognize both the need to obtain a sexual history and when to perform genital examination. STIs can present with generalized or extragenital symptoms, the significance of which might be missed. Examples include secondary syphilis, primary HIV infection, disseminated gonococcal infection, and herpes simplex meningitis. Failure to consider a sexually acquired infection in a differential diagnosis might delay diagnosis and treatment. This chapter gives advice on how to take a sexual history and perform genital examination in both sexes. It also summarizes the common symptoms and syndromes associated with STIs and their causative pathogens, cross-referring to other chapters in the textbook.
Occupational safety
Authors: Waterman Lawrence
Published: February 2020

Any approach to occupational health must acknowledge that accidents in the workplace result in many injuries. Construction, agriculture, and primary extraction are the main causes of fatalities and serious injuries, but many more minor injuries result from all types of work. Health and safety law has developed with an emphasis on accident prevention that is based on designing and managing the working environment. Establishing this approach to safety management begins with an organization committing itself to a policy influenced by legal obligations and current good practice. While this chapter draws heavily on the UK situation, where there has been considerable experience and development of approaches to health and safety, it is incumbent on any physician to consider the work environment and whether changes to the workplace might improve not only the lot of their patients, but others potentially at risk in the workplace.
Noise
Authors: Koh David , Aw Tar-Ching
Published: February 2020

Noise can affect hearing in the occupational setting but can have other effects where exposures are non-occupational. For clinical purposes, noise is measured in decibels weighted according to the sensitivity of the human ear (dB(A)). Regardless of source, the effects of overexposure to noise are similar. Initially there is a temporary threshold shift, where reversibility of hearing loss is possible with removal away from further noise. Noise-induced hearing loss occurs following prolonged or intense exposure, with poor prospects for improvement of hearing. The classical audiogram for noise-induced hearing loss shows a 4 kHz dip. Non-auditory effects of prolonged noise exposure include annoyance, sleep disturbance, hypertension, and cardiovascular disease, stress, and impaired cognitive performance. Prevention of noise-induced hearing loss is by reducing exposure to noise at source minimizing exposure time, using hearing protection, and participating in surveillance.
Vibration
Authors: Aw Tar-Ching
Published: February 2020

Various occupations can lead to exposure to vibration, which can be transmitted to the whole body or localized to the hands. The main clinical effect of whole-body vibration exposure is low back pain. Effects from hand-transmitted vibration can be (1) vascular, with manifestations of secondary Raynaud’s phenomenon; (2) neurological, often presenting as paraesthesia and reduced sensory perception; and (3) musculoskeletal, including reduced grip strength and loss of manual dexterity. In tropical countries, as opposed to temperate climates, the clinical manifestations are predominantly neurological and musculoskeletal, instead of vascular. Management requires exclusion of differential diagnoses, and the identification and reduction of exposure to vibration at source. Diagnosis of an index case should prompt further investigation and where possible, modification of the system of work to prevent other cases from occurring.
Lightning and electrical injuries
Authors: Andrews Chris
Published: February 2020

Lightning strikes are rare accidents but carry a 10% case fatality, killing 0.1–0.3 per million population each year. During thunderstorms, the risk is increased by sheltering under trees or by being on open water, on tractors, or in open fields or in outdoor activity.

Lightning is considered to cause instant asystole. Immediate cardiopulmonary resuscitation is mandatory. Survivors might develop complications including pain syndromes and psychological sequelae. Burns are generally of minor consequence, unlike electrical injury. The most disabling consequences of the injury is generally the psychological sequelae. Meanwhile, electrocution is the fifth most common cause of workplace death, mainly affecting utilities, mining, and construction labourers. Domestic electrical accidents are common, where contact with overhead power lines, faulty power tools, and particularly using extension cords, are the most common causes, with metal ladders and antennae being particularly dangerous.
Poisoning by drugs and chemicals
Authors: Vale John A. , Bradberry Sally M. , Bateman D. Nicholas
Published: February 2020

Poisoning is usually an acute, short-lived event which necessitates immediate care, though complications such as rhabdomyolysis may persist for a few days. Less commonly, symptoms may arise only after prolonged exposure, as occurs with many heavy metals. Rarely, sequelae may not occur until many years after exposure (e.g. with vinyl chloride). It must be stressed that exposure does not necessarily equate with poisoning as uptake of the agent involved is required but, even if this occurs, poisoning does not necessarily result as the amount absorbed may be too small.

Poisoning may be accidental or deliberate; it is usually accidental in small children, but in adults it is almost invariably deliberate. Less commonly, it may be iatrogenic. Occupational poisoning is frequent in developing countries.
Diseases of affluent societies and the need for dietary change
Authors: Mann J.I. , Truswell A.S.
Published: February 2020

Nutritional problems of a country depend more upon the stage of technical and economic development than geographical location. People in affluent societies have ready access to food all year round. The diet is typically energy-dense, high in fat and often also in sugar. There are multiple sources of nutritional advice, not all based on sound science. Obesity is the most obvious and important nutritional disease in affluent societies, with comorbidities including type 2 diabetes, coronary heart disease, hypertension, some cancers, gallstones, osteoarthritis, and obstructive sleep apnoea. Obese people may also be disadvantaged by social, economic, and psychological effects. Particular dietary constituents promote or protect against coronary heart disease by their effect on cardiovascular risk factors, and some promote or protect against various cancers.
Medical management of normal pregnancy
Authors: Williams David J.
Published: February 2020

This chapter looks at the medical management of normal pregnancy, and how the global maternal mortality ratio fell by almost 50% between 1990 and 2015 and the reasons for this decline. In resource-poor nations, provision of basic antenatal facilities with community healthcare workers, improved transport, communications, and education are largely responsible. Yet despite this progress maternal deaths are still common, particularly in sub-Saharan Africa, usually from readily preventable causes that would not occur in the presence of a skilled birth attendant. In wealthy nations, new challenges to maternal health include obesity, older age, and a growing number of pregnancies in women with chronic diseases through in vitro fertilization. Pregnancy can be accurately diagnosed within a day of missing a menstrual bleed by identifying a rise in urinary human chorionic gonadotropin concentration.
Heart disease in pregnancy
Authors: Head Catherine E.G.
Published: February 2020

Pregnancy is a vasodilator state in which plasma volume and cardiac output increase such that many symptoms and signs of cardiac disease can occur physiologically. Disproportionate symptoms or abnormal signs such as a diastolic murmur require investigation as usual; necessary radiological investigations should not be withheld as the risks to the fetus are generally low. This chapter looks at the various aspects of pre-pregnancy risk assessment and delivery of the baby; heart conditions arising in pregnancy (e.g. peripartum cardiomyopathy, myocardial infarction); and managing heart conditions in pregnant women, such as valve diseases and cardiomyopathies, hypertrophic cardiomyopathy, congenital cardiac lesions, and anticoagulation.
Liver and gastrointestinal diseases of pregnancy
Authors: Heneghan Michael , Williamson Catherine
Published: February 2020

This chapter first looks at pregnancy-specific disorders that cause de novo abnormal serum liver tests in pregnancy. These include: hypertension-related liver diseases; acute fatty liver of pregnancy; intrahepatic cholestasis of pregnancy; hyperemesis gravidarum; and viral hepatitis, probably the most commonly recognized cause of jaundice occurring during pregnancy worldwide. The chapter also describes the influence of pregnancy on pre-existing diseases, the effect of these diseases on pregnancy outcome, the impact of specific drugs used to treat women with liver and gastrointestinal disorders on the fetus.
Autoimmune rheumatic disorders and vasculitis in pregnancy
Authors: Soh May Ching , Nelson-Piercy Catherine
Published: February 2020

Autoimmune diseases affect 5–7% of people, are more common in women of childbearing age, and are frequently encountered in pregnancy. They may remit or improve during pregnancy, but can flare or present in pregnancy. Many women with autoimmune rheumatic diseases have been advised against pregnancy in the past, but this is no longer appropriate with a new generation of pregnancy-friendly disease-modifying antirheumatic drugs and biological agents that afford excellent disease control without compromising fertility. Nevertheless, many women with autoimmune rheumatic diseases are older and have more comorbidities (i.e. hypertension, obesity, diabetes, cardiovascular disease, and so on) when they do attempt pregnancy. This chapter looks at the importance of planned pregnancies with good preconception advice from clinicians knowledgeable in both the disease process and its effects on pregnancy (and lactation), and vice versa.
Malignant disease in pregnancy
Authors: Crawford Robin A.F.
Published: February 2020

Cancer in pregnancy is rare, affecting less than 1 in 1,000 live births. It may be specific to pregnancy (gestational trophoblastic disease) or incidental to it, the less infrequent conditions being melanoma, lymphoma, and cervical malignancy. Tumours of the uterine cervix, ovary, breast, or thyroid can metastasize to the placenta, but not to the fetus. Gestational trophoblastic disease arises from fetal chorion and is a malignant transformation of the placenta. Melanoma and haematological tumours, which also can invade the placenta, may cross into the fetal circulation. Pregnancy may cause enlargement of a pituitary tumour and a previously silent tumour may present with symptoms in pregnancy. Rare cases of colonic and neurological cancers developing in pregnancy have also been reported.
Prescribing in pregnancy
Authors: MacKillop Lucy , Frise Charlotte
Published: February 2020

Many clinicians feel uncertain about prescribing for pregnant women. Despite well-known examples of drugs that have caused serious adverse effects to the developing fetus, most medications can be used safely and effectively in this setting, provided some simple principles are followed. The first of these is that the health of the mother is the most important factor in determining the health of the fetus. Inappropriate cessation of existing medication, or failure to initiate new agents when clearly indicated, can be more harmful than the judicious use of selected medication to maintain maternal health. A medication should be prescribed in pregnancy if the benefit to the mother, and therefore indirectly to the fetus, outweighs the potential risk of fetal exposure.
Symptoms of gastrointestinal disease
Authors: Woodward Jeremy
Published: February 2020

The skilful analysis of symptoms indicating disorders of the digestive system is an integral part of the practice of internal medicine. Many patients with abdominal symptoms do not have easily defined organic conditions. The traditional skills of taking a careful history and examining the patient thoroughly are invaluable in managing patients who have functional disorders such as ‘irritable bowel’, nonulcer dyspepsia, nonspecific diarrhoea, recurrent abdominal pain, and somatization disorder. The enormous advances in endoscopy, scanning, and other investigative techniques have not made clinical diagnosis less important. Most gastrointestinal disorders are minor self-limited conditions of uncertain cause or are functional in nature, thereby often eluding definition even if extensive diagnostic procedures are (unnecessarily) employed. At the other extreme, the early suspicion of life-threatening disease and prompt referral of patients for investigation depends on clinical judgement.
Colonoscopy and flexible sigmoidoscopy
Authors: East James E. , Saunders Brian P.
Published: February 2020

Colonoscopy involves full oral bowel preparation and planned examination of the whole large bowel, while flexible sigmoidoscopy is usually performed after a phosphate enema and visualizes only the rectum and left colon. In expert hands, after appropriate explanation to the patient (which increases the chances of the procedure being well tolerated), and (usually) some form of ‘conscious sedation’, total colonoscopy is possible in 98 to 99% of cases in the absence of obstruction, a severely ulcerated colon, or other contraindication. The indications for colonoscopy are wide and constantly expanding, and are likely to continue to do so until alternative less invasive techniques (‘virtual colonoscopy’ or genetic tests) are perfected. Common indications include patients with or requiring (1) bleeding, anaemia, or occult blood loss; (2) chronic diarrhoea or known inflammatory bowel disease, which is accurately and easily assessed by endoscopy and biopsy; (3) polyps that can be removed endoscopically; and (4) surveillance for cancer prevention. Therapeutic colonoscopy now allows resection of almost all benign colonic polyps and some very early cancers as well as dilatation of anastomotic or Crohn’s disease strictures and stenting of malignant strictures.
Diseases of the oesophagus
Authors: Fitzgerald Rebecca C. , di Pietro Massimiliano
Published: February 2020

Defective conduit function of the oesophagus readily induces clinical symptoms and may have serious effects on nutrition and the lungs, the latter resulting from aspiration of gastro-oesophageal contents. Oesophageal pain and dysphagia caused by diseases of the muscular layer or epithelium are often disabling. The oesophagus is exposed to numerous hostile environments including carcinogens in food or those derived from tobacco, betel nuts, and other ingested sources and hence carcinomas can occur. Chronic reflux disease from exposure to corrosive upper gastrointestinal secretions is also associated with malignant disease—adenocarcinoma—as well as benign stricture formation related to the action of pepsin.
Investigation and management of jaundice
Authors: Collier Jane
Published: February 2020

Haem molecules are degraded in macrophages to biliverdin and then to bilirubin, which is selectively removed by hepatocytes from sinusoidal blood and conjugated, chiefly with two glucuronic acid moieties. Conjugated bilirubin is excreted into the bile, but in many liver diseases it refluxes back into blood from which some is filtered into and darkens the urine (choluria). In the distal intestine, conjugated bilirubin is deconjugated and reduced to a series of uro- and stercobilinogens that give the normal colour to faeces. Jaundice is the clinical sign of hyperbilirubinaemia and usually indicates disease of the liver or biliary tree. Dark urine and pale stools indicate cholestasis. Stigmata of chronic liver disease do not define the cause of jaundice. Unconjugated hyperbilirubinaemia—presents with raised serum bilirubin levels and normal other liver-related blood tests. Causes include haemolysis and benign inherited unconjugated hyperbilirubinaemia (i.e. Gilbert’s syndrome). Conjugated hyperbilirubinaemia—routine liver-related blood tests cannot alone differentiate between intra- and extrahepatic causes of jaundice although high levels of transferases suggests hepatitis (e.g. viral, autoimmune) or hepatic necrosis (e.g. paracetamol). Alcohol and drug histories are needed in those with both elevated alkaline phosphatase and transferases. Extrahepatic cholestasis should be sought by abdominal ultrasonography to detect a dilated intra- and/or extrahepatic biliary tree (and often also to reveal its cause, e.g. gallstones, tumour). Further investigation depends on the clinical context: (1) likely large bile duct disease—endoscopic retrograde cholangiopancreatography, magnetic resonance cholangiography, and endoscopic ultrasonography; (2) likely intrahepatic cholestasis—autoantibodies, immunoglobulins, and liver biopsy.
Hepatic encephalopathy
Authors: Middleton Paul K. , Shawcross Debbie L.
Published: February 2020

Hepatic encephalopathy (HE) is a significant complication of both acute and chronic liver disease, causing much morbidity and mortality. It is a complex neuropsychological condition, associated with hyperammonaemia and systemic inflammation, with a wide spectrum of symptoms. The West Haven criteria describe grades of severity from 0 (subclinical) and I (changes in awareness, mood, attention, cognition, and sleep pattern) through to IV (coma). It is further classified by the underlying aetiology: type A, due to acute liver failure; type B, secondary to portosystemic shunting; and type C, occurring in chronic liver disease in association with precipitating factors including infections, gastrointestinal bleeding, and electrolyte disorders, particularly hyponatraemia. There is no definitive test or set of diagnostic criteria to establish a diagnosis of HE, which remains primarily a clinical diagnosis of exclusion in patients with a history or clinical evidence of liver disease. Management depends on the type of HE, but for type C (the commonest type) typically includes lactulose and rifaximin. Patients with cirrhosis with ongoing overt HE despite optimal medical management have a dismal outlook and should be considered promptly for liver transplantation.
Autoimmune hepatitis
Authors: Webb G.J. , Hirschfield Gideon M.
Published: February 2020

Autoimmune hepatitis is an idiopathic inflammation of the liver attributed to immune responses against self-antigens presumed to be of hepatocyte origin. It is typically a relapsing and remitting corticosteroid-responsive condition associated with hepatitic serum liver tests, elevated gammaglobulins, and positive immune serology. Histological features are not specific but often include expanded portal tracts with a lymphoplasmacytic infiltrate. Epidemiology: predominantly affects women, may occur throughout life, has some heritable component, and 60% of patients have other autoimmune diseases. Clinical features: many patients are asymptomatic and identified through investigation of abnormal serum liver tests. Presentation may be with anorexia, nausea, hepatic discomfort, and jaundice, but others may have nonspecific malaise or extrahepatic manifestations such as arthralgia, arthritis, or fever. Clinical signs vary greatly, ranging from none to jaundice and tender hepatomegaly to fulminant hepatic failure. One-third of patients present as cirrhotic. Diagnosis: characteristic laboratory findings include elevated serum transaminase activities, hypergammaglobulinaemia (as IgG), and circulating autoantibodies (e.g. antismooth muscle antibodies, anti-liver–kidney microsomal antibodies, and antinuclear antibodies). Diagnosis depends on the combination of clinical features and biochemical, immunological, and liver biopsy abnormalities, with exclusion of viral and other aetiologies. There may be overlap features with other autoimmune liver diseases (primary sclerosing cholangitis or primary biliary cholangitis). Treatment and prognosis: the condition tends to progress to hepatic fibrosis and cirrhosis. Most cases should be treated with an immunosuppressive regimen, typically prednisolone with azathioprine in the first instance, and most require long-term immunosuppression. Crude 10-year survival rate is 65% for those presenting with cirrhosis and greater than 95% for those presenting without. End-stage decompensated cirrhosis and acute nonresponsive autoimmune hepatitis with liver failure can be indications for liver transplantation.