Seminars in respiratory and critical care medicine
-
Human metapneumovirus (hMPV) is a newly discovered paramyxovirus associated with upper and lower respiratory tract infections most commonly in young children, elderly subjects, and immunocompromised patients. hMPV can cause severe infections such as bronchiolitis and pneumonia and is responsible for 5 to 10% of hospitalizations of children suffering from acute respiratory tract infections. Such infections are indistinguishable from those caused by human respiratory syncytial virus. The first hMPV infection occurs during early childhood but reinfections are common throughout life, especially in older subjects. ⋯ Promising experimental models have been developed to better understand hMPV pathogenesis and to evaluate the potential effect of different therapeutic modalities. No commercial treatments are yet available for hMPV, although ribavirin has shown activity both in vitro and in animal models. Live attenuated vaccines produced by reverse genetics have also shown good efficacy in animals.
-
The global severe acute respiratory syndrome (SARS) outbreak was the first pandemic of the 21st century. Although the outbreak was successfully controlled, evidence that SARS emerged from an animal reservoir has raised concerns that another pandemic could occur. This review discusses the likelihood of another SARS pandemic and reviews the epidemiological and clinical features of the disease with an emphasis on the clinical presentation, diagnosis, and management of SARS.
-
Lung transplantation (LT) is an appropriate therapeutic option for patients with severe, fibrocystic pulmonary sarcoidosis refractory to medical therapy. Survival rates following LT for sarcoidosis are generally comparable to other indications. Timing of transplantation for patients with sarcoidosis is challenging because mortality rates are high (27 to 53%) among sarcoid patients awaiting LT. ⋯ Early referral of patients allows for timely evaluation of patients for possible listing. If the risks specific to transplantation in sarcoidosis are considered and carefully evaluated, outcomes are reasonable and match those of other diagnoses. Recurrent sarcoidosis in the lung allografts can occur but does not affect survival or risk for complications.
-
Semin Respir Crit Care Med · Feb 2007
ReviewEpidemiology of sarcoidosis: recent advances and future prospects.
Sarcoidosis is by definition a disease of "unknown causes," but recent epidemiologic advances suggest that the long-standing definition of sarcoidosis may soon need to be amended. The recently completed ACCESS (A Case-Control Etiologic Study of Sarcoidosis) study was not able to definitively identify the "cause" of sarcoidosis, but yielded important findings regarding familial and environmental risks that have advanced our understanding of this disease. The HLA-DRB1 associations reported in ACCESS along with the results of two recently completed genome scans of sarcoidosis in German Caucasians and African-Americans, respectively, have further defined the genetics of sarcoidosis. ⋯ Although genetic studies of sarcoidosis in African-American populations are confounded by Caucasian admixture, this same admixture may be useful in identifying sarcoidosis genes linked with African ancestry. Case-only methods may be useful in identifying recent acute exposures linked to disease, genetic variants of risk, and gene-environment interactions. In summary, the epidemiology of sarcoidosis has a promising future that should eventually provide the answers to the etiologic origins of this complex disease.
-
The treatment of sarcoidosis remains controversial. Corticosteroids remain the cornerstone of therapy, but immunosuppressive, cytotoxic, and immunomodulatory agents have emerged as viable therapeutic options for patients failing or experiencing adverse effects from corticosteroids. Published data are most extensive with methotrexate, but favorable responses have been noted with leflunomide, azathioprine, antimalarial and antimicrobial agents, and tumor necrosis factor-alpha inhibitors. This review focuses on these novel therapies for sarcoidosis, including indications for use, efficacy, toxicity, and monitoring.