BackgroundAcute rheumatic fever (ARF) is an autoimmune inflammatory process that develops as a sequela of streptococcal infection. ARF has extremely variable manifestations, and remains a clinical syndrome for which no specific diagnostic test exists. Persons who have experienced an episode of ARF are predisposed to recurrence following subsequent group A streptococcal infections. The most significant complication of ARF is rheumatic heart disease, which usually occurs after repeated bouts of acute illness. Show  PathophysiologyARF is characterized by nonsuppurative inflammatory lesions of the joints, heart, subcutaneous tissue, and central nervous system. An extensive literature search has shown that, at least in developed countries, rheumatic fever follows pharyngeal infection with rheumatogenic group A streptococci. [1, 2, 3, 4] The risk of developing rheumatic fever after an episode of streptococcal pharyngitis has been estimated at 0.3-3%. [1] Investigations of rheumatic fever occurring in the aboriginal populations of Australia suggest that streptococcal skin infections might also be associated with the development of rheumatic fever. [5, 6] and that group C and G streptococci may also serve as initiating pathogens. [7] Although several classic group A streptococcal emm types are considered to be rheumatogenic and most likely to be associated with acute rheumatic fever, in Oceania and Hawaii, group A streptococcal strains not traditionally associated with rheumatic fever have been found to cause the disease. [8] This diversity of potential inciting group A streptococcal strains also appears to be a common phenomenon in lower and middle income countries. [9] Molecular mimicry accounts for the tissue injury that occurs in rheumatic fever. Both the humoral and cellular host defenses of a genetically vulnerable host are involved. In this process, the patient's immune responses (both B- and T-cell mediated) are unable to distinguish between the invading microbe and certain host tissues. [10] T helper 1 and cytokine Th27 appear to be key mediators of rheumatic heart disease. [11, 12] The resultant inflammation may persist well beyond the acute infection and produces the protean manifestations of rheumatic fever. EpidemiologyFrequencyUnited States The incidence of ARF has declined markedly in the past 50 years in both the United States and Western Europe. Most Western physicians see only the late sequelae of rheumatic heart disease; the diagnosis of an acute case is usually reason enough for a grand rounds presentation. This remarkable decline of rheumatic fever likely reflects improved socioeconomic conditions, as well the decline in prevalence of the classically described rheumatogenic strains of group A streptococci. Following 2 decades of almost total absence, a resurgence of ARF occurred in the 1980s among middle-class White children in Salt Lake City, Utah. [13] Clusters were also reported in US Army and Navy training camps during the same period. [14] These limited outbreaks were associated with mucoid rheumatogenic strains that were rarely seen in the preceding 20 years. Today, ARF remains a rarity in most of the United States, although Hawaii and American Samoa continue to see a significant number of cases, many of which are caused by streptococcal strains not usually associated with rheumatic fever in persons of Polynesian descent. [8, 15] International In developing countries, the magnitude of ARF is enormous. Recent estimates suggest that 33.4 million people worldwide have rheumatic heart disease and that 300,000-500,000 new cases of rheumatic fever (approximately 60% of whom will develop rheumatic heart disease) occur annually, with 230,000 deaths resulting from its complications. Almost all of this toll occurs in the developing world. [16, 17, 18] The incidence rate of rheumatic fever is as high as 50 cases per 100,000 children in many areas. Areas of hyperendemicity (eg, indigenous populations of Australia and New Zealand) see an incidence of 300-500 cases per 100,000 children, whereas the rates are approximately 50-fold lower in their nonindigenous compatriots. [6] Rheumatic fever in the 21st century appears to be largely a disease of crowding and poverty. Even within developing countries with overall high rates of ARF, the segments of populations of poorer socioeconomic status and with higher rates of malnutrition suffer disproportionately. [19] Mortality/MorbidityCardiac involvement is the most serious complication of rheumatic fever and causes significant morbidity and mortality. As stated above, about 60% of the approximately 470,000 patients diagnosed with ARF annually eventually develop carditis, joining the approximately 33 million worldwide with rheumatic heart disease. Those with rheumatic heart disease are at a high risk for additional cardiac damage with subsequent bouts of ARF and require secondary prophylaxis. Morbidity due to congestive heart failure (CHF), strokes, and endocarditis is common among individuals with rheumatic heart disease, and about 1-1.5% of persons with rheumatic carditis die of the disease annually. [6, 16, 18] RaceARF is predominantly a disease of developing countries and is concentrated in areas of deprivation and crowding. It is rampant in the Middle East, in sub-Saharan Africa, in the Indian subcontinent, in certain areas of South America, in Oceania, and especially among the indigenous populations of Australia and New Zealand. Although a genetic predisposition to ARF clearly exists, [1, 20, 21] the disease does not seem to have a major racial predisposition, as it was once common in the United States and Europe and seems to decline in any locale where living conditions improve. SexRheumatic fever does not have a clear-cut sexual predilection, although certain clinical manifestations, such as mitral stenosis and Sydenham chorea, are more common in females who have gone through puberty. AgeARF is most common among children aged 5-15 years. It is relatively rare in infants and uncommon in preschool-aged children. ARF occurs in young adults, but the incidence of first episodes of ARF falls steadily after adolescence and is rare after age 35 years. [6] The lower rate of ARF in adults may represent a decreased risk of streptococcal infections in this cohort. Recurrent episodes, with their predisposition to cause or exacerbate valvular damage, occur until middle age.
Author Mark R Wallace, MD, FACP, FIDSA Infectious Disease Physician, Skagit Valley Hospital, Skagit Regional Health Disclosure: Nothing to disclose. Coauthor(s) Larry I Lutwick, MD, FACP Editor-in-Chief, ID Cases; Moderator, Program for Monitoring Emerging Diseases; Adjunct Professor of Medicine, State University of New York Downstate College of Medicine Larry I Lutwick, MD, FACP is a member of the following medical societies: American Association for the Advancement of Science, American Association for the Study of Liver Diseases, American College of Physicians, American Federation for Clinical Research, American Society for Microbiology, Infectious Diseases Society of America, Infectious Diseases Society of New York, International Society for Infectious Diseases, New York Academy of Sciences, Veterans Affairs Society of Practitioners in Infectious Diseases Disclosure: Nothing to disclose. Specialty Editor Board Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference Disclosure: Received salary from Medscape for employment. for: Medscape. Richard B Brown, MD, FACP Chief, Division of Infectious Diseases, Baystate Medical Center; Professor, Department of Internal Medicine, Tufts University School of Medicine Richard B Brown, MD, FACP is a member of the following medical societies: Alpha Omega Alpha, American College of Chest Physicians, American College of Physicians, American Medical Association, American Society for Microbiology, Infectious Diseases Society of America, Massachusetts Medical Society Disclosure: Nothing to disclose. Chief Editor Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America; Fellow of the Royal College of Physicians, London Michael Stuart Bronze, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Medical Association, Association of Professors of Medicine, Infectious Diseases Society of America, Oklahoma State Medical Association, Southern Society for Clinical Investigation Disclosure: Nothing to disclose. Additional Contributors What is the most common cause of rheumatic fever?Rheumatic fever is an inflammatory disease that is rare in the United States but common in some other parts of the world. It primarily affects children between the ages of 6 and 16, and develops after an infection with streptococcal bacteria, such as strep throat or scarlet fever.
How does Streptococcus pyogenes cause rheumatic fever?In some people, repeated strep infections cause the immune system to react against the tissues of the body including inflaming and scarring the heart valves. This is what is referred to as rheumatic fever.
Can Group G strep cause rheumatic fever?Group C and group G streptococci have recently been associated with acute rheumatic fever. The aboriginal population of Australia, where streptococcal pharyngitis is extremely rare, shows the highest incidence worldwide of rheumatic heart disease.
Is rheumatic fever a virus?Rheumatic fever is caused by a bacterium called group A Streptococcus. This bacterium causes strep throat or, in a small percentage of people, scarlet fever. It's an inflammatory disorder. Rheumatic fever causes the body to attack its own tissues.
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