Acute rheumatic fever

While rheumatic fever is relatively uncommon except where there are poor and crowded living conditions, sporadic acute attacks continue to occur in a family or pediatric medical practice. The physician''s role in management of the sore throat in the diagnosis of suspected cases of rheumatic fever and in follow-up for continued prophylaxis is discussed. The frequency of admissions and presenting features of 159 patients with acute rheumatic fever is reviewed. Continued surveillance is required if we are to achieve a further reduction in attack rate and complications.     

Rheumatic heart disease: future prospects

Acute rheumatic fever develops after an inadequate immune response to throat streptococcal infection that induces the production of antibodies reacting against cardiac endothelial cells. Valve damage may lead to irreversible cardiac valve sequela (rheumatic heart disease) with further evolution towards severe valve dysfunction and heart failure. The disease has been almost eradicated in Western countries with the development of living conditions and prevention policies, including primary prevention (treatment of sore throats) and secondary prevention (long term administration of antibiotics). However, rheumatic heart disease remains a major health problem in developing countries. Recently, echocardiography identified children with mild features of the disease, thereby allowing early treatment.     

RHEUMATIC FEVER IN COLLEGE STUDENTS

The results of three independent surveys concerned with rheumatic fever and heart disease in students at the University of California were assembled and found to be in close agreement. A full 2 per cent of all students believed they had had rheumatic fever; and several times that proportion gave a history of one of the rheumatic manifestations. Only 0.25 per cent had demonstrable rheumatic heart disease and 0.1 per cent had congenital heart disease.Physiologic murmurs may occur in 3 per cent or more of students entering college.Penicillin prophylaxis is important in persons with rheumatic heart disease, but it is important not to put a label of rheumatic heart disease on persons who think they have had rheumatic fever but who have no demonstrable heart disease. Long term penicillin prophylaxis or other long term prophylactic procedures directed against rheumatic fever are not indicated unless the diagnostic criteria for rheumatic fever are clearly met or unless rheumatic heart involvement is definitely present.     

Streptococcal Superantigen,Mitogenic Factor,and Pyrogenic Exotoxin B Expressed by Streptococcus pyogenes

Abstract

Streptococcus pyogenes is a Gram-positive human bacterial pathogen that causes pharyngitis, tonsillitis, skin infections (impetigo, erysipelis, and other forms of pyoderma), acute rheumatic fever (ARF), scarlet fever (SF), poststreptococcal glomerulonephritis (PSGN), a streptococcal toxic shock syndrome (STSS), and necrotizing fasciitis. These infections are some of the most economically and medically important conditions that affect humans. For example, globally, ARF is the most common cause of pediatric heart disease. It is estimated that in India more than six million school-aged children suffer from rheumatic heart disease (1). In the United States, “sore throat” is the third most common reason for physician office visits and S. pyogenes is recovered from about 30% of children with this complaint (2). It has been estimated that there are 25–35 million cases of streptococcal pharyngitis per year in the United States, and these infections cause 1–2 billion dollars per year in direct health care costs (3,4). Although the continued great morbidity and mortality caused by S. pyogenes in developing nations, the significant health care financial burden attributable to group A streptococci in the United States, and increasing levels of antibiotic resistance (5), have highlighted the need for a fuller understanding of the molecular pathogenesis of streptococcal infection, it has been the relatively recent intercontinental increase in streptococcal disease frequency and severity (6,7) that has resulted in renewed interest in S. pyogenes virulence factors and host-parasite interactions.     

Mucosal immune function comparison between amenorrheic and eumenorrheic distance runners

This study examined the effects of amenorrhea on mucosal immune function and susceptibility to upper respiratory tract infection (URTI) in elite female distance runners. Based on their menstrual cycles during the prior year, 21 elite, collegiate, female distance runners were designated as eumenorrheic runners (ERs; n = 8; 19.9 ± 0.8 years) or amenorrheic runners (ARs; n n = 13; 20.0 ± 0.3 years). Resting saliva and blood samples were collected in the morning. The secretory immunoglobulin A (SIgA) concentration was measured using enzyme-linked immunosorbent assay. The SIgA secretion rate was calculated. Serum 17β-estradiol concentrations and serum progesterone concentrations were measured using radioimmunoassay. Subjects reported the appearance of URTI symptoms (sore throat, headache, runny nose, coughing, or fever), if any, during the prior month. The serum estradiol concentration and salivary SIgA secretion rate were significantly lower for ARs than for ERs (p < 0.05). Serum progesterone concentration was not significantly different between groups. Higher frequencies of headache, runny nose, coughing, and fever were observed in ARs than in ERs. Results show that athletic amenorrhea with low estrogen might accelerate downregulation of mucosal immune function in athletes and enhance susceptibility to infection.     

Bacterial determinants of persistent throat colonization and the associated immune response in a primate model of human group A streptococcal pharyngeal infection

Group A streptococcal (GAS) pharyngitis and the subsequent bacterial colonization of the human throat elicit an immune response that may precipitate acute rheumatic fever in a susceptible host. To study the bacterial determinants that influence throat colonization and induction of humoral immunity, we characterized the behavior of GAS strains in a baboon model. An M-type 3 clinical isolate of GAS typical of strains that cause pharyngitis and invasive infection was recovered from the pharynx of six out of six baboons for at least 6 weeks after oral inoculation. By contrast, an isogenic mutant deficient in M protein failed to colonize most animals or was rapidly cleared. An isogenic mutant deficient in hyaluronic acid capsule colonized five out of six animals, but only persisted in the pharynx for 14–21 days. Colonized animals developed serum anti- streptolysin O (SLO) and anti-M protein immunoglobulin (Ig)G. The kinetics of the antibody responses were similar to those seen after human infection. Peak titres increased with the duration of throat carriage. Colonization with GAS prevented recurrent colonization after challenge with the homologous wild-type strain, but not after challenge with a strain of different M protein type. Early clearance of the M protein-deficient strain was associated with increased susceptibility of this strain to phagocytic killing in non-immune serum, whereas clearance of the acapsular strain was associated with increased susceptibility to phagocytic killing in the presence of specific antibody. These studies support critical and distinct effects of the GAS M protein and capsule on throat colonization and induction of humoral immunity in a model that reproduces important features of pharyngeal colonization and immune response following human infection.     

Socioeconomic factors in the etiology of rheumatic fever

In a case control study we evaluated the effects of socioeconomic and some other factors on the risk of Rheumatic Fever (RF) occurrence. We compared 148 patients, with RF first attack, with 444 controls individually matched to the patients for age, sex, and place of residence. The unemployment of parents was found to be the most closely related to RF, the estimated relative risk (RR) being 10.37 (95 per cent confidence limits 5.31 to 20.24). Among other socioeconomic factors, the following were found to be significantly related to RF: low education of mother, the RR being 2.58 (CL 1.38 to 4.83), change of place of residence during last 5 years, the RR being 5.00 (CL 1.52 to 7.93) and poor living conditions, that is, deteriorated condition of dwellings, the RR being 1.83 (CL 1.12 to 2.98), home dampness, with the RR of 2.48 (CL 1.34 to 4.61) and home crowding expressed as more then 2 persons per room, the RR being 1.72 (CL 1.08 to 2.72), less then 5 m2 of living space per capita, with the RR of 2.83 (CL 1.19 to 6.71) and sleeping in bed with other person, giving the RR of 1.65 (CL 1.02 to 2.66). Out of other factors observed, that were the subject matter of the study, history of frequent sore throat and family history positive on RF were found to be significantly more frequent in patients then in their controls, with corresponding RR of 2.01 (CL 1.41 to 2.89) and 2.81 (CL 1.68 to 4.69) respectively.     

The Sero-epidemiology of Coxiella burnetii in Humans and Cattle,Western Kenya: Evidence from a Cross-Sectional Study

Evidence suggests that the intracellular bacterial pathogen Coxiella burnetii (which causes Q fever) is widespread, with a near global distribution. While there has been increasing attention to Q fever epidemiology in high-income settings, a recent systematic review highlighted significant gaps in our understanding of the prevalence, spatial distribution and risk factors for Q fever infection across Africa. This research aimed to provide a One Health assessment of Q fever epidemiology in parts of Western and Nyanza Provinces, Western Kenya, in cattle and humans. A cross-sectional survey was conducted: serum samples from 2049 humans and 955 cattle in 416 homesteads were analysed for C. burnetii antibodies. Questionnaires covering demographic, socio-economic and husbandry information were also administered. These data were linked to environmental datasets based on geographical locations (e.g., land cover). Correlation and spatial-cross correlation analyses were applied to assess the potential link between cattle and human seroprevalence. Multilevel regression analysis was used to assess the relationships between a range of socio-economic, demographic and environmental factors and sero-positivity in both humans and animals. The overall sero-prevalence of C. burnetii was 2.5% in humans and 10.5% in cattle, but we found no evidence of correlation between cattle and human seroprevalence either within households, or when incorporating spatial proximity to other households in the survey. Multilevel modelling indicated the importance of several factors for exposure to the organism. Cattle obtained from market (as opposed to those bred in their homestead) and those residing in areas with lower precipitation levels had the highest sero-prevalence. For humans, the youngest age group had the highest odds of seropositivity, variations were observed between ethnic groups, and frequent livestock contact (specifically grazing and dealing with abortion material) was also a risk factor. These results illustrate endemicity of C. burnetii in western Kenya, although prevalence is relatively low. The analysis indicates that while environmental factors may play a role in cattle exposure patterns, human exposure patterns are likely to be driven more strongly by livestock contacts. The implication of livestock markets in cattle exposure risks suggests these may be a suitable target for interventions.     

DIAGNOSIS OF RHEUMATIC FEVER AND LIKE CONDITIONS—Evaluation of Certain of the Acute Phase Reactants in a Single Specimen of Blood

Certain of the acute phase reactant tests were performed on the same specimen of blood from persons with the following states: Normal, acute respiratory disease, streptococcosis, acute rheumatic fever, acute glomerulonephritis, acute rheumatoid arthritis, inactive rheumatic fever, lupus erythematosus, malignant disease, obesity, asthma, and allergic rhinitis. Of the tests performed, the mucoprotein-tyrosine and the antistreptolysin-0 titer when done together appeared to be the most discriminating. It is suggested that the performance of such tests on the same sample of blood might aid in differentiating mild acute rheumatic fever and acute rheumatoid arthritis from each other and also from other disease states.     

Role of infection in the pathogenesis of rheumatic diseases

Advanced immunological technology has revealed immunological abnormalities not only in some chronic and autoimmune connective tissue disorders but also in conditions like infective arthritis where infection apparently seems to play the only role. On the other hand role of infection in the pathogenesis of some connective tissue disorders has recently gained much importance from the observation of clinical, pathological and immunological similarities between these diseases and certain infectious diseases occurring in animal models. Meanwhile, knowledge gained into human leucocyte-A system and its association with certain diseases opens another angle in etiopathogenesis of certain rheumatic diseases. It has been postulated that adaptive mechanism of a microbe or the binding between the human leucocyte-A molecule and carbohydrate moiety of a microbe may set up an autoimmune reaction and in the presence of some triggering factors in the environment may lead on to disease manifestations. An attempt has been made to discuss the role of infection in the outcome of rheumatic diseases such as septic arthritis, polyarteritis nodosa, rheumatic fever, enteropathic arthritis, ankylosing spondylitis, rheumatoid arthritis and systemic lupus erythematoses in genetically susceptible individuals producing immunological abnormalities.     

Experience of a Wyoming County Streptococcal Control Project

Figures from Natrona County, Wyoming, during the period 1957-1959 and from the Papago Indian Health Service in Arizona during the years 1970-1982 indicate that a vigorous control program targeted to school children that used throat culturing to detect group A streptococci and to recommend adequate treatment effectively lowered the incidence of first attacks of rheumatic fever. Statistics from the Wyoming Department of Public Health for the years 1972-1983 recorded a consistently lower rate of rheumatic fever in Natrona County, where such a control program was maintained, than for the rest of the state, although the national decline in rheumatic fever incidence makes these figures more difficult to assess. Experience gained in these programs may be valuable for third world countries where rheumatic heart disease is still a major cause of death and disability.     

Protective effect of antibiotics against serious complications of common respiratory tract infections: retrospective cohort study with the UK General Practice Research Database

Objective To determine the extent to which antibiotics reduce the risk of serious complications after common respiratory tract infections.Design Retrospective cohort study.Setting UK primary care practices contributing to the general practice research database.Data source 3.36 million episodes of respiratory tract infection.Main outcome measures Risk of serious complications in treated and untreated patients in the month after diagnosis: mastoiditis after otitis media, quinsy after sore throat, and pneumonia after upper respiratory tract infection and chest infection. Number of patients needed to treat to prevent one complication.Results Serious complications were rare after upper respiratory tract infections, sore throat, and otitis media, and the number needed to treat was over 4000. The risk of pneumonia after chest infection was high, particularly in elderly people, and was substantially reduced by antibiotic use, with a number needed to treat of 39 for those aged ≥65 and 96-119 in younger age groups. Conclusion Antibiotics are not justified to reduce the risk of serious complications for upper respiratory tract infection, sore throat, or otitis media. Antibiotics substantially reduce the risk of pneumonia after chest infection, particularly in elderly people in whom the risk is highest.     

Minimum amount of penicillin prophylaxis required to control Streptococcus pyogenes epidemic in closed community.

The prophylaxis required to control an epidemic of Streptococcus pyogenes throat infection in a junior detention centre has been reported. In a further epidemic an attempt was made to determine the minimum amount of penicillin required to control the outbreak. Oral penicillin (0.5 g) given as a single daily dose for 10 days to all boys after entry proved effective. The added risk of relatively deprived adolescent boys developing rheumatic fever is stressed.     

Fatal diphtheria in an older woman

A previously healthy 68-year-old woman presented with fever and sore throat. Her condition was initially diagnosed as necrotizing streptococcal tonsillitis and was treated with penicillin G, given intravenously. A swab of her throat taken for culture at the time of admission yielded Corynebacterium diphtheriae 48 hours later. At that time an electrocardiogram showed new T-wave inversion — evidence of diphtheritic myocarditis. She was immediately given 60 000 units of equine diphtheria antitoxin (following a test dose), but later that day she began choking, became apneic and died. The patient had not received any immunizing agents as a child, and no antitoxin was detected in a blood sample obtained prior to administration of the antitoxin. Her death re-emphasizes the seriousness of diphtheria, an infection to which many elderly people are susceptible.     

Coronary Artery Vasospasm Complicating Acute Myocarditis: A Rare Association

A 17-year-old boy had a 2-day prodrome of fever and mild sore throat followed by 2 episodes of severe anginal chest discomfort and substantial transient ST-segment elevations in the anterior leads of the electrocardiogram. A subsequent evaluation showed the 2 episodes were most likely coronary vasospasm complicating acute viral myocarditis.     

Blood groups of the ABO system of chronic carriers of typhoid bacteria and typhoid patients in Uzbekistan]

Blood groups of the ABO system were studied in 186 chronic carriers of typhoid bacilli and in 392 patients with typhoid fever from various districts of the Uzbek SSR. In comparison with control (healthy persons), carriers displayed a higher percentage of persons with A (II) blood group (50.88 and 42.64 against 37.51 and 32.13 in control) and a lesser percentage of persons with the O (I) blood group (21.05 and 22.48 against 32.93 and 32.07 in control). These data demonstrated that predisposition of persons with the A (II) blood group to chronic typhoid carrier state was characteristic of the Asian part of the country. In comparison with control, there were significantly less persons with the O (I) blood group and more with the AB (IV) blood group. Possible correlative mechanisms between the blood group and the typhoid infection and the development of chronic typhoid carrier state is discussed.