Mural endocarditis caused by Salmonella virchow: survival with conservative treatment

We describe a case of endocarditis caused by Salmonella enterica serotype virchow, which was treated conservatively with antibiotics alone. It is the only reported case of survival from salmonella endocarditis with conservative treatment, and the first reported case of endocarditis caused by Salmonella virchow. The changing prevalence, virulence patterns and importance of salmonella species in endocarditis are discussed.     

Salmonella prosthetic valve endocarditis

We report the case of a 69-year-old man with an aortic valve bioprosthesis in whom a diagnosis of Salmonella typhimurium prosthetic valve endocarditis was made. During the prolonged hospital admission early aggressive antibiotic therapy and early valve replacement surgery were the deciding factors enabling him to survive this otherwise lethal condition.     

Salmonella tricuspid endocarditis in an intravenous drug abuser with human immunodeficiency virus infection

We describe a case of Salmonella tricuspid endocarditis in an intravenous drug abuser with human immunodeficiency virus infection. He was successfully treated with antibiotics with no clinical relapse. To our knowledge, this is the first case of this kind reported in the literature. Physicians should be on the alert for this potentially curable cardiac complication of human immunodeficiency virus infection.     

A rare case of Lactobacillus acidophilus presenting as mitral valve bacterial endocarditis

Lactobacillus acidophilus is a gram-positive rod that is a commensal of human mucosal tissues. They are usually considered nonpathogenic flora of the mouth, gut, and female genital tract. Lactobacillus is a rare cause of endocarditis with less than 50 cases reported in the world literature to date. We report the case of a 63-year-old woman who developed native mitral valve endocarditis secondary to L. acidophilus, and examine the literature regarding this rare entity.     

The heart as a target for oestrogens

Observational studies have consistently shown a markedly decreased risk of cardiovascular disease in postmenopausal women when treated with oestrogens. This review discusses plausible mechanisms for the physiological effects of oestrogens in healthy and diseased hearts. Oestrogens have well-documented effects on blood lipids and the regulators of the cardiovascular system, which should reduce risk. In addition, the heart is a primary target for oestrogens with functional oestrogen receptors in the coronary vasculature and on cardiac myocytes and fibroblasts. Rapid oestrogen effects include vasodilatation and anti-arrhythmic effects by actions on ion channels, and some of these effects may be pharmacological rather than physiological. Longer term responses to physiological levels of oestrogen include an increased expression of nitric oxide synthase in myocytes and endothelial cells as well as proinflammatory and pro-arrhythmic effects. Oestrogens induce growth of non-proliferating fibroblasts but inhibit the replication of proliferating fibroblasts. In contrast to the observational studies, two randomised, controlled studies of oestrogen and progestins in postmenopausal women with coronary heart disease have now shown increased coronary events, especially in the first year of study, and no change in the progression of coronary atherosclerosis. Further studies of the complex effects of oestrogens on healthy and diseased animal models are essential. Large clinical trials of the newer selective oestrogen receptor modulators to lower cardiovascular risk in both males and females should be considered as a priority.     

Functional tricuspid regurgitation secondary to aortic annular abscess: An unusual presentation of infective endocarditis

An unusual case of aortic annular abscess is presented, in which the patient presented with features of gross tricuspid regurgitation. There was no direct involvement of the tricuspid valve. Tricuspid regurgitation disappeared following surgical repair of the annular abscess. The present case also illustrates the utility of trans-oesophageal echocardiography in establishing the diagnosis and planning surgical intervention.     

A rare case of Listeria monocytogenes presenting as prosthetic valve bacterial endocarditis and aortic root abscess

Listeria monocytogenes is a gram-positive bacillus that is rarely associated with infections in the general population. Those susceptible to this pathogen include neonates, pregnant women, and the immunocompromised. The most common clinical manifestations of listeriosis are bacteremia and meningitis. Endocarditis caused by L. monocytogenes is rare with less than 60 cases reported in the world literature. We report the case of an 81-year-old man who suffered aortic prosthetic valve listeria endocarditis, and examine the literature regarding this rare manifestation of human listeriosis.     

Balloon mitral valvuloplasty at Monash Medical Centre: follow up of 201 procedures over an 11-year period

Over a period of 11 years from 1988 to 1999, 201 patients underwent balloon mitral valvuloplasty (BMV) at Monash Medical Centre, Australia. Before BMV,133 patients (66%) were symptomatic with minimal activity or at rest. BMV increased mitral valve area and cardiac output, and reduced transmitral, left atrial and pulmonary pressures, with infrequent procedural complications (<8%). At the initial 3-month follow up after BMV, symptoms were absent or minimal in 178 patients (89%), with 85% remaining event free at 12 months. At long-term follow up (median: 30 months; range: 0-129 months), cumulative event-free survival was 73% after 5 years. After BMV, 37 patients (18%) underwent mitral valve surgery, while a repeat BMV was performed in three patients (1.5%). The results of this series provide additional data for the growing body of evidence which suggests that BMV is a relatively safe and effective procedure for producing long-term benefit in patients with symptomatic mitral stenosis.     

The zoonotic potential of rotavirus

Rotaviruses are generally species-specific, but cross-species transmission is possible, as has been demonstrated experimentally. Several case studies have indicated infection of humans by animal rotaviruses. Comparison of genetic sequences of human and animal rotaviruses often reveals close identity. Surveillance of circulating rotaviruses in the human population has revealed the presence of several uncommon genotypes. Many of these have been found in domestic animals, and it is possible that they arose in the human population through zoonotic transmission. The low incidence of uncommon strains would suggest that such transmission, or at least the establishment of an animal rotavirus or a human/animal reassortant virus in the human population, does not happen with any great frequency. However, many millions of people will be exposed year on year to animal rotaviruses. This happens within farming communities, and potentially to visitors to the countryside. There may be some measure of environmental contamination through livestock excrement. This exposure may not result in high levels of infection, but some infection could occur. There may be a continual input of rotavirus strains or sequences into the human population from the animal population albeit at a very low level.     

The prevalence and pattern of pulmonary thromboembolism in the Chinese in Kong Kong

The prevalence and clinical pattern of pulmonary thromboembolism was studied by a multifaceted approach. This documented the occurrence of pulmonary thromboembolism among the Chinese and confirmed an increasing incidence in Hong Kong, although comparatively it was still much lower (about one-tenth) than that found in western communities. Their clinical pattern, regarding presentation, risk factors, clinical features and response to thrombolytic therapy, conformed well with those reported in the west, but perhaps appeared in a milder form. The strong association of pulmonary thromboembolism with varicose veins and immobilisation would appeal for recommending routine heparinisation in Chinese patients having these combinations. Our findings will stimulate more interest in the comparative study of the haematological profile and the ethnic particulars of the Chinese.     

The size of pancreatic pseudocyst does not influence the outcome of invasive treatments

BACKGROUND: Authors generally agree that Giant Pancreatic Pseudocysts (> 10 cm) have a lower spontaneous resolution and are more difficult to treat than smaller pancreatic pseudocysts. This study was carried out on two groups of patients with larger and smaller pancreatic pseudocysts (pancreatic pseudocysts > 10 cm versus pancreatic pseudocysts < 10 cm), and aims to establish whether the size of pancreatic pseudocysts is a factor influencing treatment outcomes. PATIENTS AND METHODS: In a retrospective study, we examined 71 patients with pancreatic pseudocysts following an episode of acute pancreatitis, which were treated in our hospital from 1980 to 2000. Forty-one (57.5%) patients had a large pancreatic pseudocyst. Most patients underwent invasive treatments: 9 (12.6%) had percutaneous drainage, 37 (52.1%) open surgery and 13 (18.3%) endoscopic cyst gastrostomy. 12 patients (16.9%) of the 71 were cured with medical therapy alone. RESULTS: As far as the aetiology of the pancreatitis, location and number of the cysts were concerned, no major differences emerged between the two groups, although large pancreatic pseudocysts followed more severe pancreatitis (P = 0.0005). All giant pancreatic pseudocysts required invasive treatments; 40% of the pancreatic pseudocysts < 10 cm were successfully treated with medical therapy alone. No statistical differences were found regarding hospital mortality, morbidity, recurrence rate and hospital stay among the patients treated invasively. CONCLUSIONS: Giant pancreatic pseudocysts more often require invasive therapy due to persistent symptoms or complications. Treatment outcomes do not seem to be influenced by the size of the pancreatic pseudocysts.     

The effect of hyperbaric oxygen therapy on the bout of treatment for soft tissue infections

OBJECTIVES: Hyperbaric oxygen (HBO) therapy is often combined with antibiotic therapy for infections such as gas gangrene and osteomyelitis. Although numerous investigations have been undertaken to assess the effect of adjunctive HBO therapy on the treatment of infections, the bout of treatment has not been referred in the previous investigations. The purpose of this retrospective study was to evaluate the efficacy of HBO therapy on the bout of treatment for soft tissue infections. PATIENTS AND METHODS: In the period between 1994 and 2001, we treated 23 patients with soft tissue infections. Nine patients were treated with antibiotic chemotherapy alone, and 14 patients were treated with a combination of antibiotic chemotherapy and HBO therapy. The mean bout of treatment was compared between these two groups. RESULTS: The mean bout treated with a combination of antibiotic and HBO was significantly shorter than that with antibiotic alone. CONCLUSION: Our result indicates that HBO therapy combined with antibiotic therapy is able to shorten the bout of treatment for soft tissue infections. Therefore, we recommend HBO therapy combined with antibiotic therapy for soft tissue infections.     

The evolution of experimental Trypanosoma cruzi cardiomyopathy in rabbits: further parasitological, morphological and functional studies

Young rabbits (1–2 months of age) inoculated with trypomastigote forms of the Colombia strain of Trypanosoma cruzi have been shown to develop cardiac pathological changes (together with parasitological and immunological alterations) which are very similar to those observed in the acute and chronic phases of Chagas' disease in man. The cardiac alterations in the acute phase are characterized grossly by slight cardiomegaly with dilatation of the right-sided chambers. Microscopically they are characterized by mild focal myocarditis. The chronic phase is characterized by moderate to marked cardiomegaly with hypertrophy and dilatation of both ventricular chambers. There is thinning of the apical region (apical aneurysm), particularly of the left ventricle. Focal myocarditis is seen microscopically with areas of myocytolytic necrosis, atrophic and hypertrophic myofibers, an inflammatory response predominantly composed of mononuclear cells and interstitial fibrosis. Cineventriculography in the left ventricle of rabbits during the chronic phase disclosed regional myocardial dysfunction, with typical apical systolic bulging. The pathogenesis of Chagasic cardiomyopathy is briefly discussed in the light of these findings. Our investigation has further shown that this animal model is particularly suitable for studies on the mechanisms, pathology and treatment of Chagas' heart disease.     

The streptozotocin-diabetic rat as a model of the chronic complications of human diabetes

BACKGROUND: Diabetes in humans induces chronic complications such as cardiovascular damage, cataracts and retinopathy, nephropathy and polyneuropathy. The most common animal model of human diabetes is streptozotocin (STZ)-induced diabetes in the rat. METHODS: This project assessed cardiovascular, ocular and neuropathic changes over a period of 24 weeks post STZ administration in rats. RESULTS: STZ-diabetic rats (n = 96) showed stable signs of diabetes (hyperglycaemia, increased water and food intake with no increase in bodyweight): 52% of untreated STZ-diabetic rats (n = 50) survived 24 weeks after STZ administration. STZ-diabetic rats were normotensive with slowly developing systolic and diastolic dysfunction and an increased ventricular stiffness. Ventricular action potential durations were markedly prolonged. STZ-diabetic rats developed stable tactile allodynia. Cataracts developed to presumed blindness at 16 weeks but proliferative retinopathy was not observed even after 24 weeks. CONCLUSION: The chronic STZ-diabetic rat mimics many but not all of the chronic complications observed in the diabetic human. The chronic STZ-diabetic rat may be a useful model to test therapeutic approaches for amelioration of chronic diabetic complications in humans.     

The influence of early intervention in acute myocardial infarction on long-term mortality and morbidity as assessed in the Göteborg metoprolol trial

The mortality and morbidity were assessed during a 2-year follow-up in an acute intervention trial in suspected acute myocardial infarction with metoprolol (a selective β₁-blocker). On admission to the trial, the 1395 participating patients were randomly allocated to metoprolol or placebo for 3 months. Thereafter, if there was no contraindication, patients with infarction and/or angina pectoris were continued on metoprolol for 2 years. A lower mortality was observed after 3 months in patients randomised to metoprolol. The difference remained after 2 years. The difference in 2-year mortality rate was restricted to patients randomised early after onset of pain. Late infarction was observed more often in the placebo group during the first 3 months. When the two groups thereafter were treated similarly, the difference successively declined and did not remain after 2 years. A similar incidence of angina pectoris was observed in the two groups at each check up. During the early recovery period, more patients in the metoprolol group returned to work. No such difference was observed later on.