Echocardiographic prediction of clinical outcome in medically treated patients with aortic stenosis

BACKGROUND

The onset of symptoms is crucial in the natural history of severe aortic stenosis. In contrast, the impact of the degree of valve obstruction and left ventricular dysfunction on clinical outcome in terms of progression of symptoms and mortality is undefined.

METHODS AND RESULTS

Between April 1989 and June 1996, 108 patients (75% male, aged 68.7 +/- 10.3 years) with pure and isolated aortic stenosis of at least moderate degree had a complete Doppler echocardiography. Left ventricular end-diastolic and end-systolic diameters, thickness of ventricular septum, mass and ejection fraction, and maximal instantaneous aortic gradient were measured. Patients were followed up through March 1999. Sixty-five patients who underwent aortic valve replacement were censored at the time of surgery. The end point was considered to be death or symptomatic progression (onset of new symptoms or worsening of symptoms). At the time of diagnosis 64 (59%) were in New York Heart Association (NYHA) class I-II and 44 (41%) in NYHA class III-IV. After a mean follow-up of 46 +/- 21 months 6 patients died and 45 had worsening of symptoms. Univariate predictors of clinical outcome (death and worsening of symptoms) included left ventricular end-diastolic diameter (hazard ratio 1.03, P =.08), left ventricular end-systolic diameter (HR 1.04, P =.012), and left ventricular septum thickness (HR 1.14, P =.009) but not the degree of aortic obstruction. Multivariate predictors of clinical outcome were left ventricular septum thickness (P =.016) and left ventricular end-systolic diameter (P =.008).

CONCLUSION

In patients with various degrees of aortic stenosis the rate of clinical outcome is predicted by left ventricular function and septum thickness. Therefore both the left ventricular and aortic valve gradients should be taken into account when choosing the timing of intervention.

Comparison between low-dose dobutamine echocardiography and thallium-201 scintigraphy in the detection of myocardial viability in patients with recent myocardial infarction

AIM

To compare the predictive value of thallium-201 single photon emission computed tomography (SPECT) scintigraphy (Sci) and low-dose dobutamine echocardiography (Dob) in predicting late recovery of dysfunctioning myocardium in patients with recent, uncomplicated myocardial infarction (MI).

METHODS AND RESULTS

19 patients (18 male, aged 58+/-8 years) with recent MI and ejection fraction <50% (35.5+/-8.3%) underwent 5-15 microg/kg per min Dob, rest-redistribution Sci and coronary angiography, respectively, 14+/-6, 16+/-7 and 17+/-5 days after MI. On an eleven-segment ventricular model devised to compare Dob and Sci segment by segment, each dysfunctioning ventricular segment was considered viable if it showed recovery of mechanical function at the echocardiographic follow-up, performed 6.3+/-1.5 months after revascularization (five PTCA, five GABG) or medical therapy. Among the 104 dysfunctioning segments, of which 26 (25%) showed recovery at follow-up, Dob and Sci gave a concordant response in 50 (48%, k = 0.13), correctly predicting the recovery (or not) of function in 42. Forty-two of 54 discordant responses were due to segments judged viable only by Sci and which had no recovery at follow-up (of these 37 were akinetic or severely hypokinetic at baseline). At the segment-by-segment analysis, the sensitivity, specificity, and accuracy in predicting recovery of function at follow-up were, respectively, 69, 88 and 84% for Dob as against 88, 36 and 49% for Sci (P<0.001 for both specificity and accuracy, P=NS for sensitivity).

CONCLUSION

In patients with recent MI, the specificity of Dob in the detection of myocardium capable of late mechanical recovery is significantly higher with respect to Sci, whereas sensitivity is slightly, not significantly higher for the latter. It is conceivable that Sci detects viable myocardium even if it is transmurally limited to epicardial layers in segments with severely impaired mechanical function in which viability will not affect late recovery of function.

The role of myocardial viability in deriving benefit from reestablishing infarct-related artery flow after acute myocardial infarction

Early, sustained patency of the infarct-related artery (IRA) induces myocardial salvage, which preserves left ventricular (LV) function and mediates better long-term outcome. However, the time course and the mechanisms of muscle recovery after myocardial infarction are not completely understood. A large body of evidence suggests that most of the improvement occurs during the hospital phase and is related to early and sustained thrombolysis in myocardial infarction 3 flow in the IRA. Nevertheless, the relationship between IRA status and regional and global LV mechanics in the chronic phase of the disease remains controversial. Some late recovery may occur, either spontaneously or after revascularization, even in the absence of documented myocardial ischemia. The interplay between vessel patency, coronary flow grade and severity of the residual stenosis, and the presence of stunned or hibernating myocardium in the area at jeopardy may explain this delayed improvement. Although there seems to be a limited time window in which myocardium can be salvaged, timely testing for viability, particularly in patients with poor LV function, is justified even in a later phase of the disease to challenge potential cardiac recovery.

Long-term prognostic value of the stenosis of the infarct-related artery and the presence of viable myocardium in akinetic ventricular regions in infarcted patients

BACKGROUND

Recent studies have reported that adequate perfusion of the infarct-related artery improves survival in patients with myocardial infarction, independently of left ventricular pump function. However, it is not known whether or not this reduction in mortality is independent of myocardial viability within the infarct zone. The aim of this study was to evaluate the prognostic value of the patency of the infarct artery and the presence of myocardial viability in akinetic regions in patients with myocardial infarction.

METHODS

Low-dose dobutamine echocardiography was performed in 154 patients with recent or previous myocardial infarction and known coronary anatomy. In each patient three vascular regions were defined. Each akinetic region was considered viable if function improved during dobutamine echocardiography, and irrorated by a not stenotic akinetic area-related artery if the supplying vessel had a stenosis < 75% or had been successfully revascularized within 1 month of dobutamine echocardiography.

RESULTS

At follow-up of 34 +/- 14 months, 19 patients died of cardiac death. At univariate Cox analysis end-diastolic and end-systolic volumes, ejection fraction, previous myocardial infarction, regional wall motion score index, and stenosis of the akinetic area-related artery were related to mortality. At multivariate analysis, stenosis of the akinetic area-related artery remained a significant predictor of mortality (p = 0.04), with higher mortality (13/66 vs 6/88, p = 0.02) in patients with a stenotic akinetic area-related artery, without differences in ejection fraction (35 +/- 9 vs 34 +/- 10%). Mortality was lower in patients with myocardial viability if they had a not stenotic akinetic area-related artery (1/43 vs 4/21, p = 0.02), while no difference was found among non-viable patients, with or without stenosis of the akinetic area-related artery (5/45 vs 9/45).

CONCLUSIONS

The present study confirms the prognostic role of the patency of the infarct-related artery. However, it suggests that the lower mortality in patients with a patent artery supplying akinetic infarcted regions is related to the presence of myocardial viability in these regions.

Acute anterior myocardial infarction: increased dye intensity in the myocardial risk area after coronary angioplasty is associated with reduction of diastolic volumes

BACKGROUND

Myocardial perfusion in the risk area during the acute phase of myocardial infarction has been extensively investigated over the last few years. The so-called "no-reflow" or "low-reflow phenomenon" (absence of myocardial perfusion despite patency of the infarct-related coronary artery) was shown to correlate with worse postinfarction remodeling, in particular when myocardial contrast echocardiography was used. The aim of this study was to determine, during routine coronary angiography performed before and after coronary angioplasty (PTCA) during the acute phase of myocardial infarction, the existence of the no-reflow phenomenon and its relation with ventricular remodeling, by evaluating the dye video density in the myocardial risk area. This confirmation by a different diagnostic technique may serve to highlight the role of myocardial perfusion as an index of prognosis in the clinical setting of acute myocardial infarction.

METHODS

Twenty-six patients (23 males, 3 females, mean age 57 +/- 8.7 years) who underwent either rescue (n = 11, 42.3%) or primary PTCA, according to clinical indications, of the left anterior descending coronary artery during an acute anterior myocardial infarction and who did not have stenosis of the left circumflex or right coronary artery, were retrospectively selected from a 6 year intake. The extent of coronary stenosis was assessed using biplane quantitative coronary angiography, while end-diastolic and end-systolic volume indexes, together with regional wall motion, were computed from echocardiography performed in the first 24 hours and at 6 months. Patients were subdivided into two groups on the basis of dye video intensity in the risk area, as assessed from images obtained during left main coronary artery injections before and immediately after PTCA. It was used a subtraction technique (Group A: increased video intensity, n = 12; Group B: no change, n = 14), assuming that higher peak intensity reflects greater myocardial blood volume. Three patients in Group B with ineffective PTCA were excluded, so that the final number of considered patients was 11.

RESULTS

The distribution of rescue PTCA was similar in the two groups (7 in Group A vs 3 in Group B, p = 0.13) as were clinical characteristics and therapeutic regimen. There was a significant time * group interaction for end-diastolic volumes (-4.6 +/- 23% in Group A vs +22 +/- 22% in Group B, p = 0.029), whereas end-systolic volumes showed a tendency to greater dilation in Group B (+19 +/- 28% vs +0.9 +/- 31% in Group A), although this difference was not significant (p = 0.27). No interaction was evident for increase in the vessel area (+46 +/- 12.5% in Group A vs +43.2 +/- 13.6% in Group B, p = 0.99), or for extent of regional dysfunction (+3.08 +/- 10.9 chords in Group A vs -2.5 +/- 9.5 chords in Group B, p = 0.50).

CONCLUSIONS

The detection of myocardial blood volume in the risk area using dye video intensity during left main dye contrast injection, is useful to distinguish whether there is improved perfusion at the muscular level, following successful angioplasty of the infarct-related coronary artery. Lack of improved myocardial perfusion has an adverse effect on left ventricular volumes independently of coronary stenosis resolution and regional wall motion changes in the time.

Treatment of hypertrophy of the inferior turbinate: long-term results in 382 patients randomly assigned to therapy

A number of surgical techniques are commonly performed to control the symptoms of inferior turbinate hypertrophy unresponsive to medical treatment. We report long-term results in 382 patients randomly assigned to receive electrocautery (62), cryotherapy (58), laser cautery (54), submucosal resection without lateral displacement (69), submucosal resection with lateral displacement (94), and turbinectomy (45). Outcomes of objective test results from rhinomanometry, acoustic rhinometry, mucociliary transport time, and secretory immunoglobulin A levels were compared to the symptom scores before and yearly after surgical treatment. These data indicate that submucosal resection with lateral displacement of the inferior turbinate results in the greatest increases in airflow and nasal respiratory function with the lowest risk of long-term complications.

Dentin desensitizing effects of Gluma Alternate, Health-Dent Desensitizer and Scotchbond Multi-Purpose

PURPOSE

To evaluate the effects of topical applications of Gluma Alternate, a Gluma Desensitizer version with reduced glutaraldehyde content, Health-Dent Desensitizer and Scotchbond Multi-Purpose (SMP) on hypersensitive erosion/abrasion lesions.

MATERIALS AND METHODS

55 patients were included in the trial with at least three teeth each presenting severe sensitivity. From a total of 184 teeth, 69 were treated with Gluma Alternate, 58 with Health Dent and 51 treated SMP, serving as a control. Sensitivity was recorded as response to cold air stimulus prior to treatment, immediately after the topical application of the agents, and after 1 week, 1 month and 6 months.

RESULTS

Both Gluma Alternate and SMP showed significant reduction in sensitivity between pre- and postoperative pain scores (P < 0.05). The post-treatment sensitivity scores (0 and 1) were no different between 1 week and 6 months. In the Health-Dent group only 10 of the 58 teeth showed sensitivity reduction. For this reason the remaining 48 teeth received a "rescue treatment" with Gluma Desensitizer. At the end of the 6-month observation time, all teeth treated with Gluma Alternate, Gluma Desensitizer, and SMP showed no or very little dentin sensitivity.

Left atrial filling volume can be used to reliably estimate the regurgitant volume in mitral regurgitation

OBJECTIVES

The objective was to analyze the accuracy and diagnostic value of the estimated regurgitant volume of mitral regurgitation using 1) left atrial volume variation during ventricular systole (left atrial filling volume) and 2) the percent of systolic pulmonary vein velocity integral compared with its total.

BACKGROUND

Left atrial filling volume (LAfill), which represents the atrial volume variation during ventricular systole, has been used for the assessment of mitral regurgitation severity. A good correlation with invasive semiquantitative evaluation was found, but with an unacceptable overlapping among grades. The reason could be the absence of information concerning the contribution of blood entering into the left atrium from the pulmonary veins.

METHODS

Doppler regurgitant volume (Dpl-RVol) (mitral stroke volume - aortic stroke volume) was measured in 30 patients with varying degrees and etiological causes of mitral regurgitation. In each patient atrial volumes were measured from the apical view, using the biplane area-length method. The systolic time-velocity integral of pulmonary vein flow was expressed as a percentage of the total (systolic-diastolic) time-velocity integral (PVs%). These parameters were used in this group of patients to obtain an equation whose reliability in estimating Dpl-RVol was tested in a second group of patients.

RESULTS

In the initial study group, with linear regression analysis the following parameters correlated with Dpl-RVol: end-systolic left atrial volume (R2=0.37, p=0.0004); LAfill (R2=0.45, p < 0.0001); PVs% (R2=0.56, p < 0.0001). In multiple regression analysis the combination of LAfill and the percent of the systolic pulmonary vein velocity integral (PVs%) provided a more accurate estimate of regurgitant volume (R2=0.88; SEE 10.6; p < 0.0001; Dpl-RV=6.18 + (1.01 x LAfill) - (0.783 x PVs%). The equation was subsequently tested in 54 additional patients with mitral regurgitation with a mean Dpl-RVol 27+/-37 ml. Estimated regurgitant volume and Dpl-RVol correlated well with each other (R2=0.90; SEE 12.1; p < 0.0001). In the test population, the equation was 100% sensitive and 98% specific in detecting a regurgitant volume higher than 55 ml.

CONCLUSIONS

Left atrial filling volume and pulmonary vein flow give a reliable estimate of regurgitant volume in mitral regurgitation.

The extent of regional wall motion abnormalities identifies patients at risk of extensive left ventricular remodeling: implications for the design of post myocardial infarction trials

BACKGROUND

The FAMIS (Fosinopril in Acute Myocardial Infarction Study) was a multicenter, placebo-controlled, double-blind trial designed to evaluate the safety and the efficacy of fosinopril in reducing left ventricular enlargement after acute anterior myocardial infarction. We evaluated the echocardiographic examinations performed during the trial in order to assess the trend of the remodeling process over time and to evaluate the role of infarct size in identifying patients at risk of progressive left ventricular dilation.

METHODS

A complete echocardiographic examination was performed on admission, before discharge and three months later. Patients undergoing coronary bypass surgery or PTCA had a further examination prior to the procedure. The echocardiograms were analyzed at a central laboratory, and the end-diastolic and end-systolic left ventricular volumes were computed by using a modified Simpson's rule technique. Regional wall motion was evaluated using the centerline method, analyzing the left ventricular boundary along 100 chords perpendicular to the centerline constructed midway between the end-diastolic and the end-systolic contours. A quantitative infarct-size index was then computed according to the number of chords with a fractional shortening equal to or less than 5%.

RESULTS

Left ventricular end-diastolic and end-systolic volume index significantly increased over time (p < 0.0001); as a result, the stroke volume increased (p < 0.0001) but the ejection fraction did not change. Patients were then divided according to the three-month infarct-size index. For both end-diastolic and end-systolic volume, not only did larger infarcts had higher volumes, but there was also a greater increase from baseline to 3 months. Moreover, larger infarcts had a lower ejection fraction, with a further reduction over the three months, while smaller infarcts had higher values and an increase over time. An infarct-size index of 25 or larger allowed prospective identification at the baseline examination of patients at risk of subsequent left ventricular dilation.

CONCLUSIONS

In conclusion, patients at greatest risk of left ventricular dilation, namely those with larger infarct size, constitute a group that is worth considering for any therapeutic effort for reducing the remodeling process. These patients could in fact benefit from therapeutic strategies aimed at the reduction of left ventricular remodeling and should be studied in clinical trials.

Prognostic value of detection of myocardial viability using low-dose dobutamine echocardiography in infarcted patients

Revascularization can improve ventricular function in patients with viable myocardium, but whether and how the presence of viable myocardium affects prognosis of infarcted patients is still far from clear. Thus, 202 patients (173 men, 59 +/- 9 years old) with a previous or recent myocardial infarction (MI) and regional asynergies underwent low-dose dobutamine echocardiography (5-15 microg/kg per min) to assess myocardial viability and were followed for a period of 16 +/- 11 months after revascularization (89 patients) or medical therapy (113 patients). Four groups of patients were defined: (1) patients with viability, revascularized (n = 64); (2) patients with viability, treated medically (n = 52); (3) patients without viability, revascularized (n = 25); and (4) patients without viability, treated medically (n = 61). Of these patients, 45 (23%) patients suffered 57 cardiac events: 18 cardiac deaths (9%), 7 MIs, 12 unstable angina, 9 heart failures, and 11 new revascularization procedures. Patients with viability, revascularized, experienced a slightly lower event rate (22%) compared with patients with viability, treated medically, patients without viability, treated medically and patients without viability, revascularized (29%, 31%, and 36%, respectively; p = not significant [NS]). The frequency of events was then evaluated in those 108 patients with an ejection fraction < or =33%, in whom 14 cardiac deaths occurred: the incidence of cardiac death was slightly lower in patients with viability, revascularized (3/37, 8%) than in the patients with viability, treated medically (4/26, 15%), patients without viability, revascularized (2/11, 18%), or patients without viability, treated medically (5/34, 15%) (p = NS). Nonfatal cardiac events were significantly fewer (p <0.05) in patients with viability, revascularized (8%) and in patients without viability, treated medically (6%) than in patients with viability, treated medically and patients without viability, revascularized (27%). In infarcted patients with severe left ventricular dysfunction, the presence of viable myocardium, if left unrevascularized, leads to further events. On the contrary, in the absence of myocardial viability, revascularization could lead to a worse prognosis than medical therapy.

[El Nino in Borbon, Ecuador]

The "global" climatic phenomenon of El Niño is described in its "local" expressions and dramatic health implications through the daily chronicle of what happens in an area of the Pacific Amazonia in Ecuador. The report is also an example of how health promoters living with the communities substantially contribute to the comprehensive surveillance of the life, and not only of the health, of micro-populations, which is the characteristics of community epidemiology.

Comparison of left ventricular function and volumes during transesophageal atrial pacing combined with two-dimensional echocardiography in patients with syndrome X, atherosclerotic coronary artery disease, and normal subjects

Nine patients with syndrome X were compared with 2 groups of patients known to have coronary artery disease (CAD) (8 patients who developed regional wall motion abnormalities [group ECHO+] and 6 patients who showed only ST depression at echo-pacing [group ECG+]) and with 6 healthy volunteer control subjects. Left ventricular function at rest was normal in all patients. End-diastolic and end-systolic volumes (ml/m2) and ejection fraction were calculated at baseline and at peak of echo-pacing using a Simpson's biplane method. No regional wall motion abnormalities were observed during the echo-pacing in patients with syndrome X or in the volunteers. End-diastolic volume decreased in patients with syndrome X, in the volunteers (from 47 +/- 11 to 30 +/- 12 and from 72 +/- 7 to 38 +/- 6, respectively, p <0.01 for both), and in ECG+ patients (from 48 +/- 10 to 33 +/- 6, p <0.05), whereas it did not change in ECHO+ patients. End-systolic volume decreased in patients with syndrome X and in the volunteers (from 17 +/- 5 to 11 +/- 4 and from 28 +/- 6 to 16 +/- 4, respectively, p <0.01 for both), whereas it did not change or else slightly increased in patients with CAD (from 18 +/- 10 to 16 +/- 5 for ECG+ patients and from 19 +/- 5 to 24 +/- 9 for ECHO+ patients, p = NS for both), regardless of whether regional wall motion abnormalities appeared. Ejection fraction decreased in ECG+ and ECHO+ patients (from 64 +/- 12 to 52 +/- 11 and from 62 +/- 9 to 44 +/- 13, respectively, p <0.01 for both), whereas it did not change in patients with syndrome X and in the volunteers (from 64 +/- 8 to 61 +/- 8 and from 61 +/- 7 to 58 +/- 7, respectively, p = NS for both). During echo-pacing in syndrome X patients no regional wall motion was detected. Left ventricular volumes and ejection fraction showed the same patterns of variation in these patients as they did in the healthy control subjects, in contrast with those patients with CAD, whether or not regional wall motion abnormalities appeared in the latter.

Macrofilaricidal effects of chloroquine on adult Onchocerca volvulus by local infiltration of palpable onchocercal nodules

The macrofilaricidal effects of local infiltration of high concentrations of chloroquine into the capsule of onchocercal nodules on adult worms of Onchocerca volvulus was determined. Six weeks post infiltration, histological examination of single nodules showed all adult worms to be dead. With nodule conglomerates, there was localized action of chloroquine only on the adult worms in the infiltrated nodule, with no diffusion of the drug to adjacent nodules. Chloroquine infiltration of young, recently formed nodules to reduce the adult worm load of infected individuals may be an alternative method to costly nodulectomy.

Successful control of onchocerciasis with community-based ivermectin distribution in the Rio Santiago focus in Ecuador

Onchocerciasis is a major blinding disease in equatorial Africa and Central and South America. Ivermectin is a safe and effective drug in the treatment of this disease and now forms the basis of disease control in most endemic areas. We report the findings of long-term control of this infection in the Río Santiago focus in Ecuador, between January 1990 and December 1996, using a strategy of giving ivermectin treatments biannually in hyperendemic communities and annually in meso- and hypoendemic communities. Ivermectin was administered by local health workers from each community. A high level of compliance to ivermectin was achieved, with 81.9% to 98.0% of those eligible receiving the drug at each treatment instance. The impact of ivermectin therapy was monitored using a cohort of 120 randomly selected infected individuals from 8 hyperendemic communities. The geometric mean microfilarial density of this group declined from 19.3 to 0 mf/mg over the 84-month observation period. Ivermectin had a significant impact on anterior segment ocular disease, acute onchodermatitis and sowda. The rate of infection of blackflies declined from 1.1% in 1989-0.08% in 1996, which is below the vectorial capacity of the Simulium vector and, as no new nodules were detected after 1994 and no children under 5 became infected over the observation period, it is likely that the transmission of this infection was interrupted in the study area.

Opposite effects of the remodeling of infarcted and non-infarcted myocardium on left ventricular function early after infarction in humans. An echocardiographic study in patients examined before and after myocardial infarction

OBJECTIVE

The purpose of this study was to evaluate infarction-related changes in the infarcted and the non-infarcted myocardium using a baseline assessment of ventricular function obtained prior to the infarction.

BACKGROUND

Experimental studies have shown that both infarcted and non-infarcted myocardium contribute to the process of left ventricular dilatation soon after the infarction, but no data exist on the effect that the infarct has on the pre-infarct ventricular morphology in humans.

METHODS AND RESULTS

10 patients, out of 721 admitted to our coronary care unit with a first acute myocardial infarction over a 3-year period, had had an echocardiographic examination performed before (354 +/- 407 days) and after (10 +/- 9 days) the infarction which were adequate for quantitative evaluation. Ventricular volume (Simpson) and regional wall motion (Centerline method) were evaluated by biplane apical sections and the endocardial length of the infarct and the non-infarct segments, imaged in a cross-sectional view at the papillary muscle level, were measured. After the infarction end-diastolic and end-systolic ventricular volume increased (P = 0.0003 and P < 0.0001, respectively); diastolic and systolic infarct segment length increased (P = 0.011 and P = 0.0008, respectively), while non-infarct segment had only diastolic lengthening (P = 0.019), without systolic changes. The ejection fraction decreased after the infarction (P < 0.0001), in inverse relation to infarct size and in direct relation to diastolic non-infarct segment lengthening. In the five patients in whom there was a significant diastolic lengthening of non-infarct segment (larger than mean +/- 2 S.D. of the interobserver variability) the decrease in ejection fraction was less than in the patients without significant lengthening of this segment (P = 0.017), despite a similar echocardiographic infarct size index.

CONCLUSION

Ventricular enlargement early after myocardial infarction is due to both infarct expansion and lengthening of non-infarct segment. However, while systolic stretching of the infarct segment is a deleterious process that accounts for the increase in end-systolic volume, diastolic non-infarct segment lengthening is the expression of a functional compensatory mechanism that counteracts the reduction of the ventricular pump function secondary to the infarction.

Primary cardiac leiomyosarcoma: seven-year survival with combined surgical and adjuvant therapy

Primary cardiac sarcomas constitute a rare entity that have been uniformly associated with poor long-term survival. A case of left atrial leiomyosarcoma involving the interatrial septum and the right atrial free wall and presenting with syncope and atrial fibrillation, is described. Two extensive surgical excisions followed by adjuvant radiation and chemotherapy improved survival with a good quality of life. This approach of combined surgical, medical and radiation therapy may offer better longterm outcome, since our patient is the longest survivor thus far reported.

Onchocerciasis and reproductive health in Ecuador

A retrospective study was performed comparing the number of spontaneous abortions in a hyperendemic area for onchocerciasis in Ecuador before and after invermectin treatment with that of a comparable non-endemic area. The frequency of spontaneous abortions was associated with a change in the community microfilarial load, suggesting that there may be a relationship between spontaneous abortions and infection with Onchocerca volvulus. In the endemic area, a significantly greater rate of spontaneous abortions was seen in the period before ivermectin distribution compared to that after the start of ivermectin treatments every 6 months. In the non-endemic area, no change in the rate of spontaneous abortions was seen over the same time period. In addition to the well-documented improvements in skin and ocular disease, ivermectin may also improve the reproductive health of endemic populations.

Onchocerciasis in Ecuador: prevalence of infection on the Ecuador-Colombia border in the Province of Esmeraldas

The prevalence of onchocerciasis infection was determined in communities on 7 rivers located in the northern area of the canton San Lorenzo, province of Esmeraldas. Diagnosis of the infection was obtained by skin biopsies and recombinant-antigen based-serology. No evidence of infection was detected in 9 communities studied along the Rio Mataje, which forms the frontier between Ecuador and Colombia, nor in 10 adjacent communities located on 5 interior rivers. Evidence for Onchocerca volvulus infection was found in 4 communities on the Rio Tululvi with the following prevalence: La Boca (3.5% by biopsy and 3.9% by serology), Guayabal (9.1% by both biopsy and serology), La Ceiva (51.5% by biopsy and 53% by serology), and Salidero (4% by biopsy and 7.7% by serology). A few individuals in these communities were seropositive for O. volvulus in the absence of detectable dermal microfilariae: these might harbor very light or prepatent infections. No clinical disease attributable to onchocerciasis was found. The infected communities will be included in the ivermectin-based National Control Program for the disease, with no evidence of the infection having extended north of the Ecuadorian-colombian border.

Onchocerciasis in Ecuador: evolution of chorioretinopathy after amocarzine treatment

AIMS

To investigate the impact of the macrofilaricidal drug, amocarzine, on the evolution of chorioretinopathy in onchocerciasis.

METHODS

A prospective uncontrolled cohort study was performed using subjects infected with Onchocerca volvulus in a hyperendemic onchocerciasis focus in Esmeraldas Province in Ecuador. Study subjects were recruited into four cohorts in which ophthalmic and parasitological data were collected for 2, 3, 4, and 5 years respectively.

RESULTS

Complete ophthalmic follow up was obtained for 294 individuals in the four cohorts. The incidence of retinal pigment epithelial atrophy tended to remain constant between cohorts while that of chorioretinal scarring with a greater observation period. The incidence rate of cases with new or extending chorioretinal lesions was greater with an increasing period of follow up. An association was seen between the cumulative microfilarial loads in the skin and the development of new chorioretinal lesions (p < 0.05). No relation was noted between cumulative microfilarial loads and the progression of existing disease.

CONCLUSION

Amocarzine therapy did not prevent the natural evolution of chorioretinal disease. It was suggested that ocular microfilariae were necessary for the induction of chorioretinopathy in previously unaffected eyes and that extension of existing disease might also be related to the presence of ocular microfilariae or to other immunological mechanisms.

[Care of skin infections in patients in peritoneal dialysis]

The incidence of exit-site infections among peritoneal home-dialysis patients was quantified following for 1 year all home dialysis patients of 23 dialysis centres. The exit site conditions were observed and classified according to Twardowsky. When an infection occurred data on its treatment were collected. 393 patients were observed. The infection occurred in 40 patients (10.1%). 82.2% of patients wear a Tenckoff catheter, 3% do not protect the exit site with any kind of dressing. The strategies adopted by different centres vary for the choice of antiseptics, the suggested frequency of changes dressing and the routine use of nasal swabs. Due to the limited number of patients with infection no association was found between tunnel direction or frequency of dressing changes and infections occurrence. Discussion on controversial aspects and the definition of common guidelines for instance for frequency of dressing changes, use of antiseptics is warranted.