Sickening or Healing the Heart? The Association of Ficolin-1 and Rheumatic Fever

Rheumatic fever (RF) and its subsequent progression to rheumatic heart disease (RHD) are chronic inflammatory disorders prevalent in children and adolescents in underdeveloped countries, and a contributing factor for high morbidity and mortality rates worldwide. Their primary cause is oropharynx infection by Streptococcus pyogenes, whose acetylated residues are recognized by ficolin-1. This is the only membrane-bound, as well as soluble activator molecule of the complement lectin pathway (LP). Although LP genetic polymorphisms are associated with RF, FCN1 gene's role remains unknown. To understand this role, we haplotyped five FCN1 promoter polymorphisms by sequence-specific amplification in 193 patients (138 with RHD and 55, RF only) and 193 controls, measuring ficolin-1 serum concentrations in 78 patients and 86 controls, using enzyme-linked immunosorbent assay (ELISA). Patients presented lower ficolin-1 serum levels (p < 0.0001), but did not differ according to cardiac commitment. Control's genotype distribution was in the Hardy-Weinberg equilibrium. Four alleles (rs2989727: c.-1981A, rs10120023: c.-542A, rs10117466: c.-144A, and rs10858293: c.33T), all associated with increased FCN1 gene expression in whole blood or adipose subcutaneous tissue (p = 0.000001), were also associated with increased protection against the disease. They occur within the *3C2 haplotype, associated with an increased protection against RF (OR = 0.41, p < 0.0001) and with higher ficolin-1 levels in patient serum (p = 0.03). In addition, major alleles of these same polymorphisms comprehend the most primitive *1 haplotype, associated with increased susceptibility to RF (OR = 1.76, p < 0.0001). Nevertheless, instead of having a clear-cut protective role, the minor c.-1981A and c.-144A alleles were also associated with additive susceptibility to valvar stenosis and mitral insufficiency (OR = 3.75, p = 0.009 and OR = 3.37, p = 0.027, respectively). All associations were independent of age, sex or ethnicity. Thus, minor FCN1 promoter variants may play a protective role against RF, by encouraging bacteria elimination as well as increasing gene expression and protein levels. On the other hand, they may also predispose the patients to RHD symptoms, by probably contributing to chronic inflammation and tissue injury, thus emphasizing the dual importance of ficolin-1 in both conditions.

Natural history of rheumatic heart disease, a 12 years observational study "penicillin bites the muscle but heals the heart"

BACKGROUND

Rheumatic Heart Disease (RHD) is amajor cause of cardiovascular morbidity and mortality in young individuals, in developing countries. Long term studies regarding natural history of RHD in Pakistan have not been reported in literature. We present our follow up observations on RHD patients at the end of 12 years since our first survey conducted in rural communities in 1994.

METHODS

Our study patients were known cases of RHD, diagnosed in cross sectional survey of rural areas of Rahimyar Khan in 1994. Second survey conducted in 2006, in which these RHD patients were evaluated in detail with history/Physical examination, 12 lead ECG, X-ray chest PA view and Echo/Doppler studies at Sheikh Zayed Medical College Rahimyar Khan.

RESULTS

Out of 57 patients enrolled in 1994, 21 patients (37%) were available for further evaluation. Overall mortality was 23%. Male to female ratio was 1:1.62. Age ranges between 20- 80 years with mean of 43 years. Only 6 patients (29%) were taking rheumatic prophylaxis (RP) and six patients had recurrent RF. Five patients (24%) developed new aortic regurgitation (AR) and 38% increased in grade of severity of lesions on Echo (none of them was on RP). Regression of mild lesions noted in six patients (all of them were on RP). Two patients underwent surgery. 10% developed new atrial fibrillation.

CONCLUSION

Unabated RF/RHD led to a very high mortality. Favourable out come observed with prophylaxis even for short period on mild or moderate RHD. Patients not on RP had severe diseases. This small study is a big blow to our claims of combating RF/RHD in the 21st century.

Rheumatic mitral valve stenosis is associated with impaired flow-mediated dilatation

It has been demonstrated that rheumatic mitral valve stenosis (RMVS) is associated with an increase in markers of endothelial dysfunction. It is not known whether this association indicates an impairment of flow-mediated dilatation (FMD) of the vascular endothelium. Thirty patients with RMVS and 30 healthy subjects were studied. FMD in patients with RMVS was significantly smaller than in healthy controls (11.9+/-0.4% vs 15.4+/-0.70%, p=0.003). The absolute change in brachial artery diameter in patients with RMVS was also significantly smaller than in healthy subjects (0.42+/-0.26 mm vs 0.64+/-0.32 mm, p<0.001). These findings suggest that vascular endothelial function is altered in patients with RMVS.

[Subacute bacterial endocarditis due to Pasteurella pneumotropica. Case Report]

Endocarditis due to Pasteurella pneumotropica are very rarely described. We report a new case of bacterial endocarditis in a 43 years-old patient with mitral stenosis. The patient was admitted to the hospital for lethargy, malaise and hemiparesis. On physical examination, a new systolic murmur was found. Transthoracic echocardiography revealed a vegetation on the mitral valve. Three blood culture sets were drawn and after 24 hours of incubation, the last two sets yielded Pasteurella pneumotropica and cell wall deficient forms (L-forms). The patient was successfully treated with gentamicin and ceftriaxone and underwent mitral valve replacement.

Infective endocarditis in dialysis patients: new challenges and old

BACKGROUND

Since the 1960s chronic hemodialysis (HD) has been recognized as a risk factor for the development of infective endocarditis (IE). Historically, it has been particularly associated with vascular access via dual lumen catheters. We wished to examine the risk factors for, and consequences of, IE in the modern dialysis era.

METHODS

Cases of IE (using the Duke criteria) at St. Thomas' Hospital (1980 to 1995), Guy's (1995 to 2002), and King's College Hospitals (1996 to 2002) were reviewed.

RESULTS

Twenty-eight patients were identified as having developed IE (30 episodes of IE). Twenty-seven patients were on long-term HD and one patient was on peritoneal dialysis (PD). Mean age was 54.1 years, and mean duration of HD prior to IE was 46.3 months. Eight patients were diabetic. Primary HD hemoaccess was an arteriovenous fistula (AVF) in 41.3%, a dual-lumen tunneled catheter (DLTC) in 37.9%, a polytetrafluoroethylene (PTFE) graft in 10.3%, and a dual- lumen non-tunneled catheter (DLNTC) in 4%. The presumed source of sepsis was directly related to hemoaccess in 25 HD patients: DLTC in 48%; AVF in 32%; PTFE in 12%; and DLNTC in 4%. Staphylococcus aureus[including methicillin resistant Staphylococcus aureus (MRSA)] was present in 63.3%. The mitral valve was affected in 41.4% of patients, aortic valve in 37.9% of patients, and both valves were affected in 17.2% of patients. Of note, 51.7% of patients had an abnormal valve before the episode of IE. In 15 cases surgery was undertaken. Fourteen patients survived to discharge, and 12 survived for 30 days. In 15 cases antibiotic treatment alone was employed; in this case, eight patients died and seven survived to discharge.

CONCLUSION

This is the largest reported confirmed IE series in dialysis patients. Infective endocarditis in HD patients remains a challenging problem-although hemoaccess via dual-lumen catheters remains a significant risk, many cases developed in patients with AVFs and this group suffered the greatest mortality. An abnormal valve (frequently calcified) was another risk factor; because valve calcification is now common after 5 years on dialysis, more effort in preventing this avoidable form of ectopic calcification may reduce the risk of developing IE.

[Subacute infectious endocarditis due to the agent of cat scratch fever: Bartonella henselae]

The diagnosis of severe mitral stenosis with left atrial thrombus was rectified at valvular replacement in a 48-year old immuno-competent man who was a cat owner. The mass in the left atrium was, in fact, a large endocarditic vegetation. Pre- and postoperative blood cultures were negative as was culture of the excised mitral valve. The diagnosis of infectious endocarditis (IE) due to Bartonella Henselae was made from a positive serological test (1600) and identification of the germ by genetic amplification. Antibiotic therapy was continued for 6 months and the patient was cured with a follow-up of 4 years. Bartonella Henselae IE is very rare (14 reported cases) and affects mainly the aortic valve, often giving rise to very large vegetations which, in half the cases, are complicated by systemic emboli. Germs like Batonella are sensitive to most antibiotics, especially the aminosides and macrolides. In Bartonella Henselae IE, valve replacement is the rule (13 out of 14 cases) and the prognosis is usually good. Sero-diagnosis of Bartonellosis should be part of the systematic investigation of all blood culture negative IE.

Long-term follow-up of open commissurotomy versus bileaflet valve replacement for rheumatic mitral stenosis

OBJECTIVE

Despite the achievements of third generation mechanical cardiac valve prostheses, conservative procedures are still considered the best surgical option for rheumatic mitral valve stenosis. To compare long-term results of open mitral commissurotomy (Group A) and mitral valve replacement with bileaflet prostheses (Group B) a 15-year follow-up study was carried out.

METHODS

From January 1981 to May 1996, 540 consecutive patients with pure isolated rheumatic mitral stenosis underwent mitral valve surgery: 300 had mitral commissurotomy and 240 valve replacement. The follow-up was 99.05% complete and ranged between 1 and 185 months in Group A and from 1 to 171 months in Group B.

RESULTS

Hospital mortality was 2% in Group A and 2.08% in Group B. Late mortality was 1% in Group A and 3% in Group B. The 10-year survival rates were 98.7% +/- 1% in Group A and 93.7% +/- 3% in Group B. There was a statistically significant difference of freedom from reoperation in Group B (97.7% +/- 1%) versus Group A (88.1% +/- 2%) (P = 0.04). In group A 14 embolic events occurred (93.7% +/- 2%), and 15 (6.52%) in Group B (83.9% +/- 7%). Haemorrhagic events were observed in 2 patients (0.68%) of Group A (99.3% +/- 0.5%) and in 3 patients (1.3%) of Group B (98.4% +/- 1%).

CONCLUSIONS

Long term results of mitral commissurotomy were more satisfactory than those obtained with bileaflet valves. Reoperation rate was higher in mitral commissurotomy.

Functional mitral stenosis resulting from a large mitral valve prosthesis vegetation

Obstruction of a prosthetic valve by an infective vegetation is a rare and life-threatening complication of endocarditis that demands emergent surgical intervention. In our patient's case, transthoracic echocardiography showed the large vegetation, transthoracic Doppler imaging showed severe obstruction of diastolic flow through the bioprosthetic valve, and transesophageal echocardiography showed that no perivalvular abscess was present. Rapid diagnosis of prosthetic valve infection and obstruction demanded application of all three major echocardiographic modalities and proved critical to the patient's recovery.