emedicine - acute rheumatic fever article by robert j mead

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Back to: eMedicine Specialties > Medicine, Ob/Gyn, Psychiatry, and Surgery > Rheumatology

Acute Rheumatic FeverLast Updated: August 10, 2001

AUTHOR INFORMATION

Section 1 of 11

Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Pictures Bibliography

Author: Robert J Meador, MD, Rheumatology Fellow, Department of Rheumatology, University of Pennsylvania Coauthor(s): I Jon Russell, MD, PhD, Director, University Clinical Research Center, Associate Professor, Department of Internal Medicine, Division of Clinical Immunology and Rheumatology, University of Texas Health Science Center at San Antonio Robert J Meador, MD, is a member of the following medical societies: Texas Medical Association Editor(s): Anne Davidson, MD, Program Director, Associate Professor, Department of Internal Medicine, Division of Rheumatology, Albert Einstein College of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, Pharmacy, eMedicine; Lawrence H Brent, MD, Chair, Program Director, Associate Professor, Department of Medicine, Division of Rheumatology, Albert Einstein Medical Center, Thomas Jefferson University; Alex J Mechaber, MD, FACP, Director of Clinical Skills Program, Assistant Professor, Department of Internal Medicine, Division of General Internal Medicine, University of Miami School of Medicine; and Arthur Weinstein, MD, Professor, Department of Medicine, Georgetown University Medical Center; Director, Division of Rheumatology, Department of Medicine, Washington Hospital Center INTRODUCTIONSection 2 of 11

Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Pictures Bibliography

Background: The incidence of acute rheumatic fever (ARF) has declined in most developed countries, and many physicians have little or no practical experience with the diagnosis and management of this condition. Occasional outbreaks in the United States make complacency a threat to public health. Diagnosis rests on a combination of clinical manifestations that can develop in relation to group A streptococcal pharyngitis. These include chorea, carditis, subcutaneous nodules, erythema marginatum, and migratory polyarthritis. Because the inciting infection is completely treatable, attention has been refocused on prevention. Pathophysiology: While the inciting bacterial agent is well known, susceptibility

factors remain unclear. The location of the streptococcal infection seems to play an important role. The clinical syndrome typically follows a streptococcal pharyngitis, but streptococcal cellulitis has never been implicated. The earliest and most common feature is a painful migratory arthritis, which is present in approximately 80% of patients. Large joints such as knees, ankles, elbows, or shoulders typically are affected. Sydenham chorea was a common lateonset clinical manifestation in the past but rarely is observed now. Carditis (with progressive congestive heart failure, a new murmur, or pericarditis) may be the presenting sign of unrecognized past episodes and is the most lethal manifestation. Genetics may contribute, as evidenced by an increase in family incidence. No significant association with class-I human leukocyte antigens (HLAs) has been found, but an increase in class-II HLA antigens DR2 and DR4 has been found in black and white patients, respectively. Evidence has been found that suggests that elevated immune-complex levels in blood samples from patients with ARF are associated with HLA-B5. Frequency:

In the US: The incidence of an acute rheumatic episode following streptococcal pharyngitis is 0.5-3%. The peak age is 6-20 years. While the incidence has declined steadily, mortality has declined even more steeply. Credit can be attributed to improved sanitation and antibiotic therapy. Several sporadic outbreaks in the United States could not be blamed directly on poor living conditions. New virulent strains are the best explanation. Internationally: Most major outbreaks occur under conditions of impoverished overcrowding where access to antibiotics is limited. Rheumatic heart disease accounts for 25-50% of all cardiac admissions internationally. Regions of major public health concern include the Middle East, the Indian subcontinent, and some areas of Africa and South America. As many as 20 million new cases occur each year. The introduction of antibiotics has been associated with a rapid worldwide decline in the incidence of ARF. Now the incidence is 0.23-1.88 patients per 100,000 population. From 1862-1962, the incidence declined from 250 patients to 100 patients per 100,000 population, primarily in teenagers. Notably, natives of Polynesian ancestry in Hawaiian and Maori populations are an exception. The incidence continues to be 13.4 patients per 100,000 hospitalized children per year.

Mortality/Morbidity:

Mortality is steadily improving as a result of better sanitation and health care. The current pattern of morbidity is difficult to measure because the first

attack of rheumatic fever follows an unpredictable course. As many as 90% of episodes are clinically contained within 3 months.

Carditis causes the most severe clinical manifestation because heart valves can be permanently damaged. The disorder also can involve the pericardium, myocardium, and the free borders of valve cusps. Death and/or total disability may occur years after the initial presentation of carditis.

Race:

An association has been reported between certain class-II HLA antigens (DR2 in blacks and DR4 in whites).

Sex:

No clear-cut sex predilection exists for the syndrome in general, but its manifestations seem to be sex-variable. For example, a predominance for certain clinical manifestations (ie, chorea and tight mitral stenosis) occurs in women, while men are more likely to develop aortic stenosis.

Age:

The initial attack of ARF occurs most frequently in persons aged 6-20 years and rarely occurs in persons older than 30 years. The disease may cluster in families. In some countries, a shift into older groups may be a trend. CLINICALSection 3 of 11

Author Information Introduction Clinical Differentials Workup Treatment Medication Follow-up Miscellaneous Pictures Bibliography

History:

The diagnosis is challenging to make for several reasons as follows:o

Older children and young adults recollect pharyngitis approximately 70% of the time. However, young children only recollect pharyngitis approximately 20% of the time. Therefore, one must maintain a higher index of suspicion with younger children who manifest signs or symptoms consistent with ARF. The rate of isolation of group A streptococci from the oropharynx is

o

extremely low in all populations.

Usually a latent period of approximately 18 days occurs between the onset of streptococcal pharyngitis and ARF. Rarely is this latent period shorter than 1 week or longer than 5 weeks.o

Typically, the first manifestation is a very painful migratory polyarthritis. Often, associated fever and constitutional toxicity develop. Acute attacks usually resolve within 12 weeks.

o

Guidelines for diagnosis published more than 50 years ago by T. Duckett Jones have been slightly revised by the American Heart Association (AHA). Prior history of a preceding group A streptococcal infection is helpful but not required. In addition, 2 major manifestations or 1 major and 2 minor manifestations must be present.o

Major manifestations include carditis, polyarthritis, chorea, erythema marginatum, and subcutaneous nodules. Minor manifestations include arthralgias and fever. Laboratory findings include elevated acute phase reactants (erythrocyte sedimentation rate [ESR] and C-reactive protein) and prolonged PR interval. A prolonged PR interval is not specific and has not been associated with later cardiac sequelae. The utility of echocardiography also is controversial.

o

The Jones criteria should be viewed as a guide to determine who is at high risk but cannot be used to define diagnosis with absolute certainty.o

An exception includes chorea, which can present as the sole manifestation of ARF, in spite of negative laboratory data. Another possible exception is indolent carditis.

o

A throat culture with positive results for Streptococcus is found in approximately 25% of patients at the time of presentation.

Physical:

Physical findings can be nonspecific and misleading; therefore, a high index of suspicion is required to make the diagnosis. Suspicious signs for carditis include new or changing valvular murmurs, cardiomegaly, congestive heart failure, and/or pericarditis.

Isolated mitral valve involvement occurs in nearly 60% of patients with carditis, followed in prevalence by combined mitral and aortic valve involvement. When present, Sydenham chorea is seldom evident at the time of initial presentation. Erythema marginatum and subcutaneous nodules are rare (

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