PubMed Health⌕ Search

Biomedical subjects

V G Fowler

Publications and source records attributed to V G Fowler.

36 records · Page 2Linked to original sources
PubMed1999

Infective endocarditis due to Staphylococcus aureus: 59 prospectively identified cases with follow-up.

Fifty-nine consecutive patients with definite Staphylococcus aureus infective endocarditis (IE) by the Duke criteria were prospectively identified at our hospital over a 3-year period. Twenty-seven (45.8%) of the 59 patients had hospital-acquired S. aureus bacteremia. The presumed source of infection was an intravascular device in 50.8% of patients. Transthoracic echocardiography (TTE) revealed evidence of IE in 20 patients (33.9%), whereas transesophageal echocardiography (TEE) revealed evidence of IE in 48 patients (81.4%). The outcome for patients was strongly associated with echocardiographic findings: 13 (68.4%) of 19 patients with vegetations visualized by TTE had an embolic event or died of their infection vs. five (16.7%) of 30 patients whose vegetations were visualized only by TEE (P < .01). Most patients with S. aureus IE developed their infection as a consequence of a nosocomial or intravascular device-related infection. TEE established the diagnosis of S. aureus IE in many instances when TTE was nondiagnostic. Visualization of vegetations by TTE may provide prognostic information for patients with S. aureus IE.

Adult↗
PubMed1999

Failure of amphotericin B colloidal dispersion in the treatment of paracoccidioidomycosis.

Although amphotericin B desoxycholate is considered the most effective treatment for disseminated Paracoccidioides brasiliensis infections, little is known about the efficacy of lipid-based formulations of amphotericin B in this infection. In this study, we treated four adults with the juvenile form of paracoccidioidomycosis with 3 mg/kg/day of amphotericin B colloidal dispersion for at least 28 days. Although all of the patients initially responded by clinical observation, all four patients relapsed within six months. The use of amphotericin B colloidal dispersion for the initial induction of paracoccidioidomycosis failed to cure this infection. Possible reasons for failure include dose, duration, or reduced efficacy of this lipid preparation. For many fungal infections, lipid-based preparations have been shown to have a therapeutic-toxic advantage, but our experience with Paracoccidioides infections suggests that more careful studies will need to be performed before they can be recommended for use in this mycosis.

Adult↗
PubMed1998

Incidence and outcome of Staphylococcus aureus bacteremia in hemodialysis patients.

BACKGROUND: Staphylococcus aureus bacteremia is frequently associated with metastatic complications and infective endocarditis (IE). The Duke criteria for the diagnosis of IE utilize echocardiographic techniques and are more sensitive than previous criteria. The documentation of IE in patients undergoing hemodialysis (HD) has become increasingly important in order to avoid the overuse of empiric vancomycin and the emergence of antibiotic resistance. METHODS: Patients who developed S. aureus bacteremia while undergoing HD at a tertiary medical center or one of four affiliated outpatient HD units were identified. Clinical outcome (death, metastatic complications, IE, and microbiologic recurrence) was assessed during hospitalization and at three months after discharge. Transthoracic and transesophageal echocardiograms were performed and the Duke criteria were used to diagnose IE. Pulse field gel electrophoresis was performed to confirm genetic similarity of recurrent isolates. RESULTS: Four hundred and forty-five patients underwent hemodialysis for 5431.8 patient-months. Sixty-two developed 65 episodes of S. aureus bacteremia (1.2 episodes/100 patient-months). Complications occurred in 27 (44%) patients. Bacteremia recurred in patients who dialyzed through polytetrafluorethylene grafts (44.4% vs. 7.1%, P = 0.0.01), and there was a trend to increased recurrence in patients who received only vancomycin (19.5% vs. 7.1%, P = 0.4). IE was diagnosed in 8 patients (12%), six of whom had normal transthoracic echocardiograms. CONCLUSIONS: Sensitive echocardiographic techniques and the Duke criteria for the diagnosis of IE should be used to determine the proper duration of antibiotic therapy in hemodialysis patients with S. aureus bacteremia. This diagnostic approach, coupled with early removal of hardware, may assist in improving outcomes.

Adult↗
PubMed1998

Outcome of Staphylococcus aureus bacteremia according to compliance with recommendations of infectious diseases specialists: experience with 244 patients.

To determine whether recommendations of infectious diseases specialists affect outcome for patients, we evaluated 244 hospitalized patients with Staphylococcus aureus bacteremia. We offered our management recommendations to each patient's physicians and then assessed the clinical outcome for both patients for whom our consultative advice was followed and those for whom our advice was not heeded. All patients were followed up for 12 weeks after their first positive blood culture. Our management advice was followed for 112 patients (45.9%) and partially or completely ignored for 132 patients (54.1%). Patients for whom our recommendations were followed were more likely to be cured of their S. aureus infection and less likely to relapse (P < .01), despite having significantly more metastatic infections (P < .01) at the outset of therapy, than were those for whom our recommendations were not followed. Failure to follow recommendations to remove an infected intravascular device was the most important risk for treatment failure. After controlling for other factors, logistic regression analysis revealed that patients whose intravascular device was not removed were 6.5 times more likely to relapse or die of their infection than were those whose device was removed. Our findings suggest that patient-specific management advice by infectious diseases consultants can improve the clinical outcome for patients with S. aureus bacteremia.

Algorithms↗
PubMed1998

In vitro resistance to thrombin-induced platelet microbicidal protein among clinical bacteremic isolates of Staphylococcus aureus correlates with an endovascular infectious source.

Platelet microbicidal proteins (PMPs), small cationic peptides released at sites of endovascular damage, kill common bloodstream pathogens in vitro. Our group previously showed that in vitro resistance of clinical staphylococcal and viridans group streptococcal bacteremic strains to PMPs correlated with the diagnosis of infective endocarditis (IE) (Wu et al., Antimicrob. Agents Chemother. 38:729-732, 1994). However, that study was limited by (i) the small number of Staphylococcus aureus isolates from IE patients, (ii) the retrospective nature of the case definitions, and (iii) the diverse geographic sources of strains. The present study evaluated the in vitro PMP susceptibility phenotype of a large number of staphylococcemic isolates (n = 60), collected at a single medical center and categorized by defined and validated clinical criteria. A significantly higher proportion of staphylococcemic strains from patients with IE was PMP resistant in vitro than the proportion of strains from patients with soft tissue sepsis (83% and 33%, respectively; P < 0.01). Moreover, the levels of PMP resistance (mean percent survival of strains after 2-h exposure to PMP in vitro) were significantly higher for isolates from patients with IE and with vascular catheter sepsis than for strains from patients with abscess sepsis (P < 0.005 and P < 0.01, respectively). These data further support the concept that bloodstream pathogens that exhibit innate or acquired PMP resistance have a survival advantage with respect to either the induction or progression of endovascular infections.

Anti-Bacterial Agents↗
PubMed1997

Bacterial endocarditis in hemodialysis patients.

Infective endocarditis (IE) is one of the most serious complications of bacteremia. Hemodialysis patients with prosthetic vascular access devices such as dual-lumen cuffed venous catheters and polytetrafluoroethylene (PTFE) grafts are at increased risk for bacteremia compared with patients with primary arteriovenous fistulae (PAVF). We present 20 cases of IE in hemodialysis patients seen at our institution over a 7-year period. Eight patients had PTFE grafts, 11 had dual-lumen cuffed catheters, and one had a PAVF. All patients underwent transthoracic echocardiography (TTE) and 16 patients also received transesophageal echocardiography (TEE). The Duke Criteria were used to characterize patients as definite or possible IE. Organisms were Staphylococcus aureus (55%), Staphylococcus epidermidis (25%), and Enterococcus sp (10%). The mitral valve (50%) was the most commonly affected valve, followed by aortic (30%) and right-sided IE (25%). Valve replacement was performed in five patients, of whom three survived hospitalization. The overall mortality rate for the series was 30%. All the dual-lumen cuffed catheters were removed, while only two of the eight PTFE grafts were removed. Four of the six patients who died had PTFE grafts, of which one was judged to be infected and removed. Echocardiography was essential to the diagnosis of IE. Vegetations were found in 50% by TTE and 81% by TEE. Six patients with no vegetations on TTE were found to have vegetations on TEE.

Arteriovenous Shunt, Surgical↗
PubMed1997

Role of echocardiography in evaluation of patients with Staphylococcus aureus bacteremia: experience in 103 patients.

OBJECTIVES: The purpose of this prospective study was to examine the role of echocardiography in patients with Staphylococcus aureus bacteremia (SAB). BACKGROUND: The reported incidence of infective endocarditis (IE) among patients with SAB varies widely. Distinguishing patients with uncomplicated bacteremia from those with IE is therapeutically and prognostically important, but often difficult. METHODS: One hundred-three consecutive patients undergoing both transthoracic (TTE) echocardiography and transesophageal (TEE) echocardiography were prospectively evaluated. All patients presented with fever and > or = 1 positive blood culture and were followed up for 12 weeks. RESULTS: Although predisposing heart disease was present in 42 patients (41%), clinical evidence of infective endocarditis (IE) was rare (7%). TTE revealed anatomic abnormalities in 33 patients, but vegetations in only 7 (7%), and was considered indeterminate in 19 (18%). TEE identified vegetations in 22 patients (aortic valve in 5, mitral valve in 9, tricuspid valve in 4, catheter in 2 and pacemaker in 2, abscesses in 2, valve perforation in 1 and new severe regurgitation in 1; 26 total [25%]). Using Duke criteria for the diagnosis of IE, definite IE was present in 26 patients (25%). Clinical findings and predisposing heart disease did not distinguish between patients with and without IE. The sensitivity of TTE for detecting IE was 32%, and the specificity was 100%. The addition of TEE increased the sensitivity to 100%, but resulted in one false positive result (specificity 99%). TEE detected evidence of IE in 19% of patients with a negative TTE and 21% of patients with an indeterminate TTE. At follow-up, cure of staphylococcal infection occurred in a similar percentage of patients with and without IE (77% and 75%, respectively). However, death due to sepsis was significantly more likely among patients with IE (4 of 26 [15%]) than among those without IE (2 of 77 [3%]) (p = 0.03). CONCLUSIONS: Our results suggest that IE is common among patients admitted to the hospital with SAB and is associated with an increased risk of death due to sepsis. TEE is essential to establish the diagnosis and to detect associated complications. Therefore, the test should be considered part of the early evaluation of patients with SAB.

Aged↗
PubMed1997

Bacillus cereus necrotizing cellulitis mimicking clostridial myonecrosis: case report and review of the literature.

We describe a case of rapidly progressive necrotizing cellulitis in an immunocompromised farmer caused by Bacillus cereus, and review 15 additional cases of serious soft tissue infection due to this organism reported in the English language literature. These cases illustrate the potential for B. cereus to cause fulminant soft tissue disease indistinguishable from that caused by clostridia.

Bacillaceae Infections↗
PubMed1994

Infective endocarditis.

Endocarditis continues to be a popular subject among medical authors. A steady stream of new papers describes evolving aspects of epidemiology, clinical manifestations, natural history, and management. Significant developments include refinements in echocardiography and diagnostic criteria, and the introduction of improved surgical techniques for dealing with the complications of endocarditis. Here we review recent publications that present useful or interesting observations.

Adult↗
PubMed1993

Efficacy of chloroquine on Plasmodium falciparum transmitted at Amani, eastern Usambara Mountains, north-east Tanzania: an area where malaria has recently become endemic.

In order to assess the response of newly endemic falciparum malaria to currently used antimalarials, a field study was conducted in Amani, Tanzania. The efficacy of chloroquine (CQ) on Plasmodium falciparum was assessed by in-vivo and in-vitro methods. Fifty-four patients with pure falciparum malaria were treated with CQ and followed daily for 3 days and weekly for one month. Eighty-three per cent of infections exhibited some degree of in-vivo resistance to CQ (46% RI, 28% RII and 9% RIII). Pretreatment blood samples were obtained from all 54 patients for in-vitro sensitivity testing for CQ, amodiaquine (AQ), quinine (QN), and mefloquine (MQ). In-vitro data correlated well with in-vivo data; 80% of successful isolates were resistant to CQ. Forty-five per cent of successful isolates were resistant to AQ, 2% to QN, and none to MQ. The antimalarial levels yielding 99% inhibition (EC99) for CQ, AQ, QN, and MQ were 12.86, 3.24, 24.09 and 0.81 microM respectively. Urine HPTLC revealed CQ metabolites in 15% of study patients who denied recent CQ ingestion and had a negative Dill-Glazko test. This implies the high rate of CQ resistance observed in this study could be due in part to the widespread use of CQ for self-medication. Although the day 3 mean CQ plasma level was higher for sensitive and RI infections than for RII and RIII infections, the difference did not reach statistical significance. Our study results confirm that P. falciparum transmitted at Amani is highly resistant to CQ.

Adolescent↗
PubMed1991

Case report: splenic infarction and acute splenic sequestration in adults with hemoglobin SC disease.

While acute splenic sequestration and splenic infarction are commonly observed in infants and young children with sickle cell anemia, they are rarely experienced by adult hemoglobin S homozygotes because the recurrent splenic infarction that takes place during childhood is typically followed by scarring, atrophy, and splenic fibrosis. Both acute splenic sequestration and splenic infarction do remain relatively common in adults with the other sickle hemoglobinopathies. These episodes are almost certainly a consequence of the persistently enlarged and distensible spleens that often remain present in these conditions. In this report, the authors describe two adult patients with hemoglobin SC disease: one who developed acute splenic sequestration and one with splenic infarction. In neither case was there a history of recent air travel or exposure to altitude. The clinical course of these two syndromes is presented, and the hematologic, radiologic, and pathologic manifestations are discussed. Because they can sometimes be difficult to distinguish from one another, and because a failure to identify acute splenic sequestration can be catastrophic, these two entities must be included in the differential diagnosis for any hemoglobin SC patient who present with an unexplained fall in hemoglobin, left upper quadrant pain, unexplained fever, or symptomatic splenomegaly.

Acute Disease↗
PubMedDate not supplied

Clostridium septicum myonecrosis presenting as a parapharyngeal abscess in a patient with aplastic anemia.

The first reported case of Clostridium septicum myonecrosis in an adult with aplastic anemia is described. The patient presented with sepsis, a parapharyngeal abscess that necessitated emergent intubation, and severe intravascular hemolysis attributed to clostridial alpha-toxin production. Despite prompt recognition and treatment, the patient died of his infection. C. septicum myonecrosis should be considered in any immunocompromised patient with sepsis, especially when accompanied by evidence of multiple sites of tissue infection.

Adult↗