bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endocarditis
Authors: Harrison James L. , Klein John L. , Littler William A. , Prendergast Bernard D. 
Published: February 2020

Abstract
Endocarditis predominantly affects the aortic and mitral valves; involvement of the tricuspid valve occurs in approximately one-fifth of cases and pulmonary valve involvement is rare. In the developing world rheumatic heart disease is the most common predisposing factor. In developed countries endocarditis is more common in older people with native valve disease and in patients with prosthetic valves and intracardiac devices (pacemakers and defibrillators). In these countries up to 50% of cases have no predisposing cardiac lesion and more cases are related to intravenous drug abuse and nosocomial infection related to invasive procedures. Mortality remains high (30%) despite advances in antimicrobial therapy and surgery, and at least 50% of cases require valve surgery. Early diagnosis, specialist management, and timely intervention are key to successful outcome.
Cardiovascular syphilis
Authors: Somers Krishna 
Published: February 2020

Abstract
Clinicians need to be aware of cardiovascular syphilis in patients at risk of infection, with the time taken from initial infection to clinical manifestation ranging from 10 to 25 years, although this is accelerated in patients with HIV infection. Inadequate or interrupted antibiotic therapy may confound the development of cardiovascular syphilis and make diagnosis difficult. In diagnosis, serological testing is the mainstay: latent or inadequately treated syphilis should be suspected with the finding of a positive non-specific treponemal serological test (e.g. rapid plasma reagin) and a positive specific treponemal antibody test (e.g. Treponema pallidum haemagglutination), but negative serology does not absolutely exclude infection with T. pallidum, particularly in an immunocompromised host. Parenteral penicillin remains the treatment of choice for cardiovascular syphilis: the World Health Organization and European and United States guidelines recommend benzathine benzylpenicillin 2.4 × 106 units administered once weekly for 3 weeks by the intramuscular route.
Tumours of the heart
Authors: Traill Thomas A. 
Published: February 2020

Abstract
Cardiac myxomas are rare benign tumours that grow in the lumen of the atria, usually the left. Most are sporadic, but they can be associated with the Carney complex, where unusual freckling is typically the most obvious clinical clue. Symptoms and signs most commonly mimic those of mitral stenosis. Systemic emboli occur in about 40% of cases. However, the most common tumour seen in adult patients is the benign papillary fibroelastoma, which should be surgically removed only if it has been discovered in the search for a source of otherwise unexplained embolism. Primary cardiac sarcomas are found more often in the right heart than in the left. Microscopic secondary deposits within the myocardium can often be found in patients who die of metastatic cancer, but these are rarely of clinical importance.
Biology and pathology of atherosclerosis
Authors: Choudhury Robin P. , Chai Joshua T. , Fisher Edward A. 
Published: February 2020

Abstract
Atherosclerotic plaques are not randomly distributed, but tend to form at the inner curvatures and branch points of arteries, where laminar flow is either disturbed or insufficient to support the normal, quiescent state of the endothelium (the lining of endothelial cells that separates the circulating blood from the arterial wall). This is an inflammatory process that involves the contribution of endothelial cells, lymphocytes, monocytes, and smooth muscle cells in conjunction with the deposition of atherogenic lipoproteins in the intimal layer of the vascular wall. The initial stage involves activation of the endothelium at regions of non-laminar flow in vessels resulting in increased permeability to Apo B-containing lipoproteins. Inflammatory cells, in particular monocytes, are recruited into the intimal layer of the vessel wall via the action of chemokines and adhesion molecules mobilized by activated endothelium.
Management of acute coronary syndrome
Authors: Kharbanda Rajesh K. , Fox Keith A.A. 
Published: February 2020

Abstract
Acute coronary syndrome (ACS) is precipitated by an abrupt change in an atheromatous plaque and/or thrombotic occlusion. This results in increased obstruction to perfusion and ischaemia or infarction in the territory supplied by the affected vessel. The clinical consequences of plaque rupture can range from a clinically silent episode, through to unstable symptoms of ischaemia without infarction, to profound ischaemia complicated by progressive infarction, heart failure, arrhythmia, and risk of sudden death. Clinical presentation with an ACS identifies a patient at high risk of further cardiovascular events requiring a defined acute and long-term management strategy. Prompt relief of pain is important, not only for humanitarian reasons, but also because pain is associated with sympathetic activation, vasoconstriction, and increased myocardial work. The management of prehospital cardiac arrest requires special attention: at least as many lives can be saved by prompt resuscitation and defibrillation as by reperfusion.
Peripheral arterial disease
Authors: Powell Janet , Davies Alun 
Published: February 2020

Abstract
The most common presentations of peripheral arterial disease are intermittent claudication and abdominal aortic aneurysm. In patients under 50 years of age the cause of disease is most likely to be genetic, congenital, immunological, infectious, or traumatic; over 50 years of age the principal risk factor is smoking. The main diagnostic method used to confirm the diagnosis of peripheral arterial disease is Doppler ultrasonography, in particular to estimate the ratio of systolic blood pressure at the ankle and in the arm, the ankle–brachial pressure index. Presents as a painful, pale, and pulseless limb, and is usually caused by thrombosis at the site of an atherosclerotic stenosis.
Essential hypertension: Definition, epidemiology, and pathophysiology
Authors: Williams Bryan , Firth John D. 
Published: February 2020

Abstract
‘Essential hypertension’ is high blood pressure for which there is no clearly defined aetiology. From a practical perspective, it is best defined as that level of blood pressure at which treatment to lower blood pressure results in significant clinical benefit—a level which will vary from patient to patient depending on their absolute cardiovascular risk.
Historically, most guidelines define ‘hypertension’ as an office blood pressure greater than or equal to 140/90 mm Hg, but some recent recommendations prefer home or ambulatory blood pressure (blood pressure) averages. When using 24 h ambulatory blood pressure or home blood pressure averages to define hypertension, the diagnostic thresholds are lower than those used with office measurement, with a value of 135/85 mm Hg typically used for both daytime ambulatory blood pressure and home measurements.
Essential hypertension: Diagnosis, assessment, and treatment
Authors: Williams Bryan , Firth John D. 
Published: February 2020

Abstract
Essential hypertension is invariably symptomless and usually detected by routine screening or opportunistic measurement of blood pressure. However, once a patient has been labelled as ‘hypertensive’ it is not uncommon for them to associate preceding symptoms to their elevated blood pressure. Some patients will claim that they can recognize when their blood pressure is elevated, usually on the basis of symptoms such as plethoric features, palpitations, dizziness, or a feeling of tension. Screening surveys have demonstrated that these symptoms occur no more commonly in untreated hypertensive patients than they do in the normotensive population. However, there are two important caveats to the symptomless nature of essential hypertension: (1) symptoms may develop as a consequence of target organ damage, (2) headache may be a feature of severe hypertension.
Idiopathic oedema of women
Authors: Firth John D. 
Published: February 2020

Abstract
Idiopathic oedema is an unsatisfactory label that is applied to women who complain of swelling, typically variable, with diagnosis requiring exclusion of known causes of oedema and (most authors would agree) demonstration of weight gain, from morning to evening, of more than 1.4 kg. The cause of idiopathic oedema is (by definition) unknown: hypotheses include abnormal capillary permeability/leakage, re-feeding oedema, and diuretic-induced oedema. There is no clear relationship to the menstrual cycle. Even if not a primary cause, the use and abuse of diuretics can complicate and exacerbate the problem. Management is difficult, but patients can be helped by a sympathetic approach from the physician and (1) encouragement to lose weight if they are obese; (2) avoidance of excess dietary salt; and (3) weaning from consumption of high doses of diuretics that can cause or exacerbate the tiredness, lethargy, weakness, and dizziness that are suffered by many.
The seriously ill or deteriorating patient
Authors: Foot Carole , Hickson Liz 
Published: February 2020

Abstract
The first step in the clinical approach to a patient who is very ill is the recognition of this fact. While experienced clinicians will intuitively recognize a seriously ill or deteriorating patient, a large body of data has demonstrated that warning signs are often missed or not acted upon, resulting in preventable harm to patients. This has led to the development and adoption of ‘track and trigger’ systems. Track and trigger systems aim to ensure that hospitalized patients undergo regular review and objective observation, with abnormal observation or staff concerns being triggers to escalate care. Escalated care may be urgent review by the treating team, or the calling of a ‘rapid response team’ to attend to a more critically ill patient. While calling criteria and team composition varies from country to country, the principle of rapidly taking skilled care to critically ill patients remains the unifying underlying principle.
Metabolic and endocrine changes in acute and chronic critical illness
Authors: Boonen Eva , Berghe Greet Van den 
Published: February 2020

Abstract
Critical illness, an extreme form of severe physical stress, is characterized by important endocrine and metabolic changes. The development of critical care medicine has made possible survival from conditions that were previously rapidly fatel, and as a result many patients now enter a prolonged phase of chronic or persistent critical illness. Acute endocrine adaptations are directed towards providing energy and substrates for the vital fight or flight response in the context of exogenous substrate deprivation. Distinct endocrine and metabolic alterations characterize the chronic phase of critical illness, which seems to no longer be solely beneficial and may hamper recovery and rehabilitation. Onset of the stressful event causes an acute activation of pulsatile hormonal release from the anterior pituitary, followed by suppression in the chronic phase of illness, ultimately resolving to normality if recovery occurs.
Respiratory function tests
Authors: Gibson G. J. 
Published: February 2020

Abstract
Respiratory function tests are used in diagnosis, assessment, and prognosis and in monitoring the effects of treatment of various respiratory conditions. In the diagnosis of specific diseases, respiratory function tests—like functional tests of other organs—inevitably have limitations. Their use as a diagnostic tool is in recognizing patterns of abnormality which characterize particular types of disease; more often they are used to quantify the severity of functional disturbance or to locate the likely anatomical site(s) of disease (airways, alveoli, or chest wall). The commonly applied tests are most conveniently classified as (1) tests of respiratory mechanics, (2) carbon monoxide uptake, (3) arterial blood gases and acid–base balance, and (4) exercise.
Bronchiolitis obliterans and cryptogenic organizing pneumonia
Authors: Kouranos Vasilis , Wells A.U. 
Published: February 2020

Abstract
The nomenclature of the bronchiolitides is complicated by the interchangeable use of pathological and clinical descriptions and a diversity of classification systems. The four primary histological patterns are: organizing pneumonia (also termed proliferative bronchiolitis and bronchiolitis obliterans organizing pneumonia); bronchiolitis obliterans (also termed obliterative bronchiolitis and constrictive bronchiolitis); follicular bronchiolitis; and diffuse panbronchiolitis. The most characteristic abnormality is a filling of alveoli with granulation tissue and buds of loose collagen and connective tissue matrix cells with a uniform appearance. Presentation is typically subacute with non-productive or minimally productive cough, insidious dyspnoea, and systemic symptoms including malaise, fever, or chills, weight loss, and myalgia. Clinical signs are non-specific. Corticosteroid therapy is usually effective, with other immunosuppressive agents given to fulminant cases or those that do not respond. Prognosis is usually good, with overall mortality less than 5%.
Lymphocytic infiltrations of the lung
Authors: Bourke S. J. 
Published: February 2020

Abstract
Lymphocytic infiltrations of the lung arise from the proliferation of bronchus-associated lymphoid tissue, resulting in a spectrum of rare conditions ranging from benign polyclonal lymphoid interstitial pneumonia to monoclonal primary malignant lymphomas of the lung. Lymphoid interstitial pneumonia is most commonly seen in Sjögren’s syndrome or other connective tissue diseases, and in association with HIV infection, and is characterized by reticulonodular shadowing on CT imaging and (usually) a good response to corticosteroids. Primary pulmonary lymphomas fall into three categories: lymphomatoid granulomatosis, low-grade B-cell lymphoma, and high-grade B-cell lymphoma. The latter require treatment with cytotoxic drugs and have a poor prognosis.
Clinical presentation and diagnosis of rheumatological disorders
Authors: Deighton Christopher , Pearce Fiona 
Published: February 2020

Abstract
Most rheumatological diagnoses are made through effective history taking and physical examination rather than investigation. Systemic symptoms, such as weight loss, anorexia, and fever, point to systemic diseases such as rheumatoid arthritis, other polyarthritides, systemic lupus erythematosus, polymyalgia, and vasculitides. Swelling of joints is a symptom commonly reported by patients with no objective evidence of this on examination. Inflammatory arthropathies should not be diagnosed unless the physician is able to identify objective swelling, if necessary by arranging a prompt review during an active episode. Diagnostic criteria for the systemic rheumatic diseases are useful in directing the history taking to verify a suspected diagnosis. Investigations are best used to confirm a strongly suspected diagnosis, already made on the basis of history and examination, not as a screening tool for rheumatic disease.
Osteoarthritis
Authors: Barr Andrew J. , Conaghan Philip G. 
Published: February 2020

Abstract
Clinical osteoarthritis (OA) is a syndrome of joint pain associated with structural deterioration of synovial joints that over time involves the whole joint organ. It is the most common form of arthritis and a leading cause of chronic pain, disability, and socioeconomic burden. Affected individuals report pain (especially on weight bearing) and joint stiffness leading to loss of muscle strength and poor joint function. This results in reduced participation in valued activities, low mood, sleep disturbance, and poor quality of life. The aetiology of joint deterioration, pain, and the interaction of the two remains unclear. OA is associated with a variety of both modifiable and non-modifiable risk factors including obesity, age, gender, occupational injury, trauma, and genetic predisposition. Obesity is the strongest potentially modifiable risk factor.
Introduction
Authors: Isenberg David A. , Giles Ian 
Published: February 2020

Abstract
About 1 in 20 people develop an autoimmune disease, many of which involve the musculoskeletal system. Young women are particularly at risk, but the development at any age of symptoms such as unexplained fever, rash, polyarthritis, Raynaud’s phenomenon, or mouth ulcers should encourage serological screening for autoimmune rheumatic or vasculitic disorder. The autoimmune rheumatic diseases are a heterogeneous group of disorders characterized by clinical involvement of the joints, connective tissues, muscles, internal organs, Raynaud’s phenomenon, and cutaneous manifestations. They include a broad clinical spectrum of disease, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), Sjögren’s syndrome, scleroderma, dermatomyositis, polymyositis, antiphospholipid syndrome (APS), and the vasculitides.
Polyarteritis nodosa
Authors: Guillevin Loïc 
Published: February 2020

Abstract
Polyarteritis nodosa (PAN) is a necrotizing angiitis, often associated with hepatitis B infection, that predominantly affects medium-sized arteries. Patients usually have systemic features; specific manifestations include peripheral neuropathy, mononeuritis multiplex, skin lesions (subcutaneous nodules, purpura), hypertension, renal insufficiency, gastrointestinal haemorrhage/perforation, and orchitis. Elevated markers of inflammation are found in most patients, but serum antineutrophil cytoplasmic antibodies are not present. Standard treatment of hepatitis B negative cases is with corticosteroids (typically initiated with intravenous methylprednisolone) and cyclophosphamide; hepatitis B positive cases are treated with an antiviral agent, corticosteroid and plasma exchange, with corticosteroid discontinued as soon as disease comes under control. Severe gastrointestinal involvement is the primary cause of early death; later deaths may result from treatment side effects.
Small vessel vasculitis
Authors: Watts Richard A. 
Published: February 2020

Abstract
Small vessel vasculitis is vasculitis affecting predominately small intraparenchymal arteries, arterioles, capillaries, and venules. There are two main types: antineutrophil cytoplasmic antibody associated and immune complex mediated. The ANCA associated vasculitides are discussed in chapter 19.3 IgA vasculitis (IgAV) was formerly known as Henoch Schönlein purpura. The revised nomenclature reflects the importance of IgA vasculitis in pathogenesis. The Chapel Hill Consensus Conference defined IgA vasculitis as ‘vasculitis with IgA1-dominant immune deposits, affecting small vessels (predominantly capillaries, venules, or arterioles)’. IgA vasculitis often involves skin and gut, and frequently causes arthritis. Glomerulonephritis indistinguishable from IgA nephropathy may occur. Its aetiology is unknown, but it frequently occurs after an infection several days to weeks before. The most frequently isolated organism is beta-haemolytic streptococcus. Drugs such as a penicillin, ampicillin, erythromycin, and non-steroidal anti-inflammatory drugs have been reported as precipitating agents. There is an association with HLA-DRB1*01 in Caucasians and there appears to be a familial association.
Osteomyelitis
Authors: McNally Martin A. , Berendt Anthony R. 
Published: February 2020

Abstract
Bacteria can penetrate bone from a contiguous focus of infection (e.g. a diabetic foot ulcer or local injury) or by haematogenous spread. Osteomyelitis is most commonly caused by Staphylococcus aureus, β-haemolytic streptococci, and—in some situations—aerobic Gram-negative rods. An acute inflammatory response causes oedema within bone and soft tissue, and thrombosis in vessels that can result in bone infarction. Pus may form within cancellous bone and beneath the periosteum, stripping it from the bone and leading to extensive necrosis that sometimes involves an entire bone. The process may become chronic and relapsing. Definitive diagnosis can only be confirmed with culture of bacteria from representative bone samples, supported by histological evidence of inflammation. This cannot be achieved in all cases and diagnosis is commonly made on the basis of clinical features and imaging. MRI is the standard and best method.
Bone cancer
Authors: Hatcher Helen 
Published: February 2020

Abstract
Benign bone tumours are common, usually asymptomatic, and discovered incidentally. Malignant primary bone tumours are uncommon but cause significant morbidity and mortality, particularly in adolescents and young adults. Bony metastases are the tumours most frequently seen in bone. Malignant bone tumours typically present with localized pain or swelling. With patients in whom the diagnosis is not clearly metastatic disease, determination of tumour size and extent is best achieved by magnetic resonance imaging, and bone biopsy is mandatory to establish a precise histological diagnosis. Osteosarcoma, chondrosarcoma, and Ewing sarcoma are the three commonest primary bone tumours. In determining management, the main clinical distinction is between localized and metastatic disease. Non-metastatic primary tumours are treated with surgery (when possible) and chemotherapy (osteosarcoma and Ewing sarcoma, sometimes chondrosarcoma). Symptomatic bony metastases are usually treated with external beam radiotherapy.
Structure and function of the kidney
Authors: Harper Steve , Unwin Robert 
Published: February 2020

Abstract
The kidneys are the archetypal organs of homeostasis. Their primary function is filtration and segregation. Through these processes they rebalance the continual electrolyte and chemical disturbances that derive from physiological and pathological metabolic processes. Electrolytes, hydrogen (H+) ions from metabolic acids, amino acids, fatty acids, plasma proteins, immunoglobulins, and metabolic products are either retained, reabsorbed, and recycled; or they are filtered, secreted, concentrated, and excreted. These processes convert approximately 120 ml/min of primary glomerular filtrate into 1 ml/min of urine. In addition, the kidneys play crucial roles in bone mineralization, the maintenance of cardiovascular tone, systemic blood pressure, and bone marrow synthetic function via their contribution to vitamin D production, the renin–angiotensin system, and erythropoiesis.