Primers

Gallstones are masses in the gallbladder or biliary tract. This Primer by Lammert et al. focuses on the formation of gallstones, summarizes the current principles of treatment of the stones and their potential complications and envisions future approaches for this widespread disease.

In 2015, an estimated 367,000 new cases of pancreatic cancer were diagnosed worldwide; this disease is aggressive and patients face a dismal overall prognosis. In this Primer, the current understanding of pathophysiological, molecular, translational and clinical aspects of pancreatic cancer are described.

Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer and has well-known risk factors, including cirrhosis and viral hepatitis. Here, Llovet and colleagues discuss the challenges and recent advances in HCC molecular characterization, diagnosis and management.

This Primer describes the mechanisms underlying the serious effects of Clostridium difficile infection, which is the leading cause of health-care-associated infective diarrhoea. Strategies for diagnosis, prevention and management are also described, illustrating the burden that C. difficile infection places on patients and society.

Atrial fibrillation occurs when cardiac electrical impulses become disordered, leading to a rapid and irregular heartbeat. Lip and colleagues discuss the mechanisms that underlie this common arrhythmia and outline current strategies and potential future developments for its diagnosis and management.

Irritable bowel syndrome (IBS) is a functional gastrointestinal disease with a high prevalence. Enck et al. describe the association between IBS and other gastrointestinal, somatic and psychiatric conditions, as well as the current view on the pathophysiology, and diagnostic and management options.

Diabetic retinopathy is a common microvascular complication of diabetes and is a major cause of vision loss in middle-aged and elderly people. In this Primer, Wong et al. discuss the epidemiology, underlying pathophysiological mechanisms, classification and diagnosis and treatment options of this condition.

Acute myeloid leukaemia is characterized by clonal proliferation of haematopoietic stem cells or progenitor cells, leading to fewer differentiated red blood cells, platelets and white blood cells. The disease presents with a rapid onset and may be fatal in weeks or months if left untreated.

Calcific aortic stenosis (AS) involves fibro-calcific remodelling of the aortic valve that causes restriction of blood flow. Pibarot and colleagues discuss the mechanisms, diagnosis and management of AS and highlight how the introduction of transcatheter-based valve replacement has transformed patient outcomes.

Kidney stones form when the urine becomes supersaturated with respect to a mineral, leading to crystal formation, growth, aggregation and retention within the kidneys. In this Primer, Khan et al. describe the contributing pathways to stone formation and the available treatments, as well as highlight the emerging management strategies.

Although IgA nephropathy is a common primary glomerulonephritis, its exact pathogenesis is not well defined. In this Primer, Lai et al. report a broad overview of the disease, from pathogenesis to therapy.

Erectile dysfunction is a multidimensional but common male sexual dysfunction involving an alteration in any of the components of the erectile response. This Primer highlights numerous aspects of the condition, summarizing various treatments and ongoing preclinical studies.

In this Primer, Dharnidharka et al. describe post-transplant lymphoproliferative disorders (PTLDs). PTLDs are a group of lymphoma-like conditions characterized by an uncontrolled proliferation of lymphoid cells as a consequence of therapeutic immunosuppression, following solid organ or haematopoietic stem cell transplantation.

Patent foramen ovale (PFO) is the most common congenital heart abnormality and is present in approximately ∼25% of the adult population. In this Primer, Homma et al. describe various aspects of PFOs, focusing on their potential relationship with stroke.

Acute rheumatic fever (ARF) is caused by an autoimmune response to group A streptococcal infection. Severe and/or repeated episodes of ARF can lead to rheumatic heart disease (RHD). Both conditions predominantly affect those experiencing economic disadvantage.

Cerebral palsy is the most common cause of movement and posture disorders caused by brain injury acquired during the antenatal, perinatal or early postnatal period. Here, Graham et al. describe this complex disease entity, the possible causes and the clinical management of the disorder.

Nonalcoholic fatty liver disease is characterized by excess accumulation of fat in hepatocytes, which can be accompanied by inflammation, cell injury and fibrosis. Here, Brunt et al. explain the pathophysiology, the current limitations in management options and the avenues for progress.

Cancers derived from follicular thyroid cells, which produce the iodine-containing thyroid hormones, have an excellent prognosis. In this Primer, Dralle et al. describe the advances in the molecular characterization of the tumours and the current state-of-the-art in diagnosis and management.

Chronic obstructive pulmonary disease (COPD) is characterized by damage to the lungs and consequent obstruction of the airways, and is strongly associated with smoking. This Primer discusses the causes and mechanisms of COPD and approaches to its diagnosis and management.

Anorexia nervosa (AN) is a psychiatric condition characterized by severe weight loss and associated problems of malnutrition. The illness perpetuates without early intervention as patients value the beliefs and behaviours contributing to their illness rather than regarding them as problematic. Here, Treasure et al. describe the current research in AN.