Primers

Haemophilia is a recessive, X-linked, genetic disease caused by mutations in the gene encoding coagulation factor VIII (in haemophilia A) or IX (in haemophilia B). Individuals living with haemophilia are susceptible to bleeding events that can occur spontaneously or as a result of injury.

Williams syndrome is a rare genetic disorder caused by the microdeletion of a region of chromosome 7q11.23. In this Primer, Pober and colleagues provide an overview of the epidemiology, genetic aetiology, diagnosis, common manifestations and management of this syndrome as well as of how quality of life is affected in individuals with Williams syndrome and their families.

This Primer reviews the epidemiology, pathophysiology, diagnosis and management of microscopic colitis (MC), a type of inflammatory bowel disease that causes persistent watery diarrhoea. This Primer also discusses the effect of MC on patient quality of life and future research priorities in this field.

Contact dermatitis results from the exposure to exogenous allergens or irritants that stimulate immune responses leading to inflammation of the skin.

Phenylketonuria is an inherited disorder of phenylalanine metabolism that can result in neurological dysfunction. This Primer reviews the epidemiology, aetiology, diagnosis and management of PKU as well as the impact on patients’ quality of life.

Alzheimer disease is a neurodegenerative disorder that causes cognitive impairment. This Primer by Knopman et al. reviews the epidemiology of cognitive manifestations and risk factors, summarizes the pathophysiology from a synaptic disorder perspective, and reviews advances in the diagnosis, management and quality of life of persons living with Alzheimer disease.

Age-related macular degeneration (AMD) is the leading cause of severe vision loss in the developed world. This Primer describes the different stages of AMD, its epidemiology, the current understanding of its pathophysiology and diagnostic modalities. Additionally, it outlines existing treatment options and highlights the outstanding issues, suggesting future research avenues.

Trauma-induced coagulopathy describes alterations in haemostasis (such as fibrinogen depletion, inadequate thrombin generation, impaired platelet function and dysregulated fibrinolysis) that can result in both uncontrolled bleeding and hypercoagulation, leading to venous thromboembolism and multiple organ failure.

Liver metastases are commonly detected in a range of malignancies originating from the pancreas, breast, colon or rectum. This Primer summarizes the epidemiology, mechanisms and diagnosis of liver metastasis, discusses the various treatment options and effects on quality of life, and highlights ongoing and future research areas.

Pneumonia is a respiratory infection of the distal airways; it can be acquired in the community or in the hospital, and it can be caused by several types of bacteria, viruses, fungi and other pathogens.

This Primer discusses the epidemiology, pathophysiology, diagnosis and treatment of tension-type headache. This Primer also summarizes the quality of life issues faced by patients and future research priorities in this field.

Gastrointestinal stromal tumours (GIST) are the most frequent of all sarcomas. In this Primer, Blay et al. present an overview of epidemiology, mechanisms of tumorigenesis and molecular subtypes of GIST. They discuss state-of-the-art GIST diagnosis and treatment, means to improve patient quality of life and outstanding research questions.

Adrenal insufficiency (AI) is an endocrine disorder characterized by adrenal hypofunction, resulting in cortisol deficiency. In this Primer, Hahner and colleagues describe the different types of AI, their epidemiology, pathophysiology and diagnosis. Additionally, the authors discuss specific challenges associated with the long-term management of this disorder and strategies to prevent adrenal crises.

This Primer by Connor and colleagues reviews the epidemiology of cannabis use, together with the epidemiology, mechanisms, diagnosis, prevention and treatment of cannabis use disorder. This Primer also discusses cannabis policy and the risks associated with high-potency cannabis products.

Duchenne muscular dystrophy is an X-linked progressive, muscle-wasting disease that manifests in childhood as difficulties with movement. This Primer by Aartsma-Rus and colleagues discusses the clinical presentation, epidemiology, pathophysiology, genetic diagnosis and treatment of this disorder.

This Primer discusses the epidemiology of penile cancer and mechanisms underlying its development, including HPV infection. The authors explain contemporary and possible future diagnostic and management approaches in localized and advanced disease and highlight important considerations around the quality of life of affected patients.

Prostate cancer is the second most common cancer and one of the leading causes of cancer-associated death in men. This Primer summarizes the epidemiology, mechanisms and diagnosis of prostate cancer, discusses treatment based on disease stage and effects on quality of life, and highlights ongoing and future research areas.

Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, is one of the leading causes of cancer-related death in the world. This Primer summarizes the current knowledge on the epidemiology, pathogenetic mechanisms and diagnosis of HCC and provides an update on key advancements in the management of this disease.

Small-cell lung cancer is a rapidly proliferating cancer with a poor prognosis and is strongly associated with exposure to tobacco carcinogens. This Primer describes the epidemiology, pathogenesis and diagnosis of the disease as well as the current management approaches and new therapies that might improve outcomes.

Tendinopathy is a multifaceted pathology of the tendon, characterized by pain and reduced function. This Primer summarizes the epidemiology, pathophysiology, diagnosis and the latest insights in the management of this disorder. Finally, the authors discuss the outstanding issues that will help achieve better outcomes in patients with tendinopathy.