Secular changes in incidence and mortality associated with Staphylococcus aureus bacteraemia in Quebec, Canada, 1991-2005

In order to examine secular changes in the incidence and mortality associated with Staphylococcus aureus bacteraemia before and after the emergence of methicillin-resistant S. aureus (MRSA), a retrospective cohort study of 815 patients with S. aureus bacteraemia was performed in the Estrie region of Quebec, Canada, between 1991 and 2005. The primary outcome was all-cause 30-day mortality. Between 1991-1993 and 2003-2005, the proportion of cases attributed to endocarditis and pneumonia increased from 4% to 11% and from 2% to 11%, respectively, while that attributed to catheter infections decreased from 49% to 17%. MRSA was almost absent in 1991-1999, but accounted for 10% and 20% of cases in 2000-2002 and 2003-2005, respectively. The population incidence of bacteraemia caused by methicillin-susceptible S. aureus (MSSA) remained stable between 1997 and 2005, while that of MRSA increased from 0 to 7.4/100 000. Risk-factors for mortality included age, co-morbidities, female gender, residence outside the city of Sherbrooke, pneumonia (OR 3.35, 95% CI 1.96-5.73) or endocarditis (OR 2.89, 95% CI 1.67-5.01) as the source, and an absence of treatment. After adjusting for confounders, patients with MRSA bacteraemia had a higher mortality rate than those with MSSA bacteraemia (OR 2.21, 95% CI 0.99-4.96, p 0.053). Mortality in patients with MSSA bacteraemia was 19% (16/83) in 1991-1993, 23% (26/113) in 1994-1996, 29% (50/173) in 1997-1999, and 28% (52/185) in 2000-2002, decreasing to 15% (28/192) in 2003-2005, which impacted on the relative mortality rates of MRSA and MSSA. MRSA did not replace, but added to, an existing stable incidence of MSSA bacteraemia.

Migration and HIV: an epidemiological study of Montrealers of Haitian origin

We aimed to determine the prevalence of HIV infection and associated risk factors among Montrealers of Haitian origin. We carried out a voluntary, anonymous survey in 7 primary care medical clinics in Montreal among 5039 persons aged 15 to 49 years born in Haiti or with at least one parent born in Haiti. The participation rate was 94.3%. Overall, HIV prevalence was 1.3% (1.6% in men and 1.1% in women). The HIV prevalence was lower among those born in Canada or who had resided in Canada longer. The prevalence among subjects who had travelled to Haiti in the previous 5 years was 2.0%, twice the rate of those who had not. The adjusted population attributable fraction of HIV infections associated with having had unprotected sex in Haiti was 10.2%. This study identified risk factors which will help in the design of more effective prevention programmes among Montrealers of Haitian origin.

Determinants of rifabutin-associated uveitis in patients treated with rifabutin, clarithromycin, and ethambutol for Mycobacterium avium complex bacteremia: a multivariate analysis. Canadian HIV Trials Network Protocol 010 Study Group

Uveitis occurred in a substantial proportion of AIDS patients receiving rifabutin, 600 mg daily, together with clarithromycin and ethambutol for treatment of Mycobacterium avium complex bacteremia. A case-control study was undertaken to examine potential risk factors for developing uveitis. Of eight parameters examined, only baseline body weight predicted the development of uveitis by both univariate and multivariate analyses (P = .001). The incidence of uveitis was 14% in patients weighing >65 kg, 45% in patients between 55 and 65 kg, and 64% in patients <55 kg. Concomitant therapy with fluconazole, a drug known to raise serum rifabutin concentrations, was not associated with an increased incidence of uveitis. The risk of uveitis was markedly reduced when rifabutin was given at 300 mg daily in combination with clarithromycin and ethambutol.

Biliary pseudolithiasis in a child associated with 2 days of ceftriaxone therapy

Ceftriaxone, a third-generation cephalosporin, is known to induce reversible precipitations in the gallbladder of children. In general, radiologic signs and symptoms will develop after 9-11 days of treatment. The authors report a case where 48 h of therapy were sufficient to develop a biliary pseudolithiasis. Clinicians and radiologists should be aware of this complication which mimics true cholelithiasis.

Blastomycosis in Quebec (1981-90): Report of 23 cases and review of published cases from Quebec

Twenty-three cases of blastomycosis were reported in a survey conducted in the province of Quebec from 1981-90. Thirteen patients resided south of the St Lawrence River and the other 10, north. Two small geographical clusters were apparent in and around the cities of Sherbrooke and Quebec. The male to female ratio was 1.6:1 and the median age was 47 years (range 26 to 77). Lung involvement was observed in 19 cases and was the only site involved in 11. Cutaneous manifestations were reported in 11 cases while bone infection (three cases) and central nervous system (CNS) infections were also noted. Diagnosis was confirmed by culture in 21 cases and by histopathology in two cases. Of the 21 culture-positive cases, 12 strains of Blastomyces dermatitidis were isolated from lungs, nine from skin, and one each from bone and brain. Serodiagnostic tests by immunodiffusion or complement fixation were positive for only one of the 10 patients known to have been tested. Ten patients were treated with amphotericin B, 11 with ketoconazole, one with fluconazole and eight underwent surgery. While amphotericin B was used in eight of the 10 earliest treated cases, ketoconazole was administered in 10 of the 13 more recent cases. Of the patients for whom follow-up data have been obtained, 21 are reported cured (one of whom was not treated) and one patient died of another cause. This survey confirms that blastomycosis is a rare disease in this endemic area and that patterns of therapy are changing.

Thymic epithelial cell transplantation in patients with acquired immunodeficiency syndrome. Evidence for infection by HIV-I of newly differentiated T cells at the site of transplantation

From October 1983 to July 1984, 11 adult AIDS patients have received single or repeated thymic grafts. All have had opportunistic infections and 3 also had Kaposi's sarcoma. Thymic tissue from infants undergoing cardiac surgery was cultured to provide a thymocyte- and fibroblast-free epithelial cell inoculum. 18-21 days post-explantation, cells and explants were injected intraperitoneally, intramuscularly or intrahepatically. Transplants were well tolerated in all cases. In 7 cases liver biopsy was performed at the time of grafting and 2 months later. Ten patients have died after a mean survival time following transplantation of 8.7 months while 1 patient was lost to follow up. Clinical improvement and absence of new opportunistic infections were apparent for 4 months following transplantation. Partial immunoreconstitution was evidenced by an increase in peripheral blood lymphocytes (8 of 10 cases) and lymphocyte subsets (7 of 10 cases) as well as by presence of T4 and T8 positive cells in the liver (5 of 7 cases). In 5 of 7 patients, double-staining immunofluorescence showed that HIV-I antigens were present in T4-phenotype cells, at the site of the graft, 2 months after grafting, but were not detected in the liver at the time of grafting. Transient immunoreconstitution, therefore, maybe related to destruction of newly differentiated T lymphocytes.

Once-daily therapy with ceftriaxone compared with daily multiple-dose therapy with cefotaxime for serious bacterial infections: a randomized, double-blind study

A randomized, double-blind study was done to compare the efficacy and toxicity of daily single-dose therapy with intravenous ceftriaxone (2 g every 24 h) with daily multiple-dose therapy with cefotaxime (2 g every 6 h) for treatment of serious bacterial infections in nonneutropenic patients. Of the 325 patients who were evaluable for toxicity, 241 (74.2%) were evaluable for efficacy. Infection sites included lung (106), urinary tract (42), skin and soft tissue (43), bone and joint (23), bacteremia (21), and hepatobiliary (5). Definite infections were present in 173 cases (71.8%) and possible infections in 68 (28.2%). Analysis of clinical and bacteriologic responses and adverse drug reactions showed no significant differences between the regimens. Values for 95% confidence limits on the differences between regimens for positive clinical and bacteriological outcomes in definite infections were -0.8% to 3.0% and -1.9% to 9.1%, respectively. Thus, daily single-dose therapy with ceftriaxone was comparable to daily multiple-dose therapy with cefotaxime in treating these bacterial infections.

Staphylococcus aureus mediastinitis: prognostic usefulness of an early medicosurgical therapy

Six cases of acute Staphylococcus aureus mediastinitis after median sternotomy were reported. Five resulted from an asymptomatic disseminator of S aureus present in the operating room. Each case was characterized by an acute bacteremic phase, occurring after a mean interval of 8.2 +/- 1.7 days after the surgical procedure; within 24 to 36 hours all patients had a temperature above 39 degrees C, toxic appearance, and marked leukocytosis. Pericicatricial inflammation was moderate, instability of the sternum was present in only two patients, and chest roentgenogram was not helpful in making an early diagnosis. No risk factor for mediasinitis in connection with the perioperative or postoperative periods was noted in cases compared with a control group of 103 patients. All strains of S aureus were susceptible in vitro to the antibiotic regimen used in prophylaxis. All patients underwent early surgical reopening of the mediastinum within 47 +/- 15 hours after the first sign of acute mediastinitis. Mediastinal debridement and continuous irrigation-suction with dilute povidone-iodine solution were associated with intravenous antistaphylococcal therapy for a period of four to six weeks. All patients survived and no recurrence was observed, a finding we think due to early diagnosis and aggressive medicosurgical therapy.

A prospective randomized trial of ceftazidime versus cefazolin/tobramycin in the treatment of hospitalized patients with pneumonia

Ceftazidime and cefazolin/tobramycin were compared in the treatment of hospitalized patients with pneumonia. Iv doses 8-hourly were: ceftazidime--2 g, cefazolin--1.5 g, tobramycin--1.7 mg/kg. For patients with pseudomonas infection randomized to cefazolin/tobramycin, ticarcillin (3 g iv 4-hourly) was used instead of cefazolin. One hundred and ten of 129 patients were evaluable (ceftazidime = 52, cefazolin/tobramycin = 58). Seventy five cases (68%) had documented pathogens of which 81% were aerobic Gram-negative bacilli. Analysis of clinical response showed no difference in overall results (P = 0.77), or separate outcomes: cured (P = 0.85), improved (P = 0.62), failed (P = 0.53), or relapsed (P = 0.50). No differences in bacteriological response were noted either: eradication (P greater than 0.10), elimination with recurrence (P greater than 0.10), persistence (P greater than 0.10). The incidence of enterococcal and fungal colonization and superinfection was the same for both regimens. There was a greater incidence of Coombs' test positivity with ceftazidime (P less than 0.01) but greater nephrotoxicity with cefazolin/tobramycin (P less than 0.02). Ceftazidime appears to be as efficacious as cefazolin/tobramycin in the treatment of hospitalized patients with pneumonia, and is less nephrotoxic.

Localized hypertrophic osteoarthropathy due to arterial graft sepsis from an enteroprosthetic fistula

The case of a 73-year-old man with localized left-lower-limb hypertrophic osteoarthropathy in association with aortic left-iliac-artery bypass and enteroprosthetic fistula was studied. The patient presented first with massive gastrointestinal bleeding and with pain and swelling of his left leg. He was hospitalized on numerous occasions for recurrent episodes of bacteremia involving enteric flora; hypertrophic osteoarthropathy and aortoduodenal fistula were documented before surgery. Symptoms and signs of hypertrophic osteoarthropathy were markedly alleviated after removal of the infected prosthesis. A review of the literature revealed seven additional patients with a similar presentation. The diagnosis of infected arterial graft with enteroprosthetic fistula may be extremely difficult, and a delay in this diagnosis may be lethal. Awareness of this uncommon association may lead to prompt diagnosis and early surgical therapy.

Legionnaires' disease in the immunocompromised host: usefulness of Gram's stain

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Infective endocarditis due to Leptotrichia buccalis: a case report

A patient with Down's syndrome presented with infective endocarditis due to Leptotrichia buccalis. The source of the infection was not detected, but the predisposing factor was a complex cardiac malformation. The disease followed a subacute course, had a number of immunologic manifestations and was successfully treated with a 28-day course of penicillin G, given intravenously. L. buccalis has never been reported before as a cause of endocarditis.

A multicentre prospective randomized trial comparing ceftazidime with cefazolin/tobramycin in the treatment of hospitalized patients with non-pneumococcal pneumonia

A multicentre prospective randomized control trial was done to compare the efficacy and toxicity of ceftazidime with that of cefazolin/tobramycin in the treatment of hospitalized patients with non-pneumococcal pneumonia. The results for 50 patients are reported in this paper; 24 in the ceftazidime group and 26 in the cefazolin/tobramycin group. Measurements of clinical response show no differences between the two groups: the same is true for bacteriological response. Minimal toxicity was seen with both treatment groups. The results support the use of ceftazidime as single-drug treatment of hospitalized patients with pneumonia.

Unexplained falciparum malaria in a patient with chronic lymphocytic leukemia

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Cryptococcosis, with emphasis on the significance of isolation of Cryptococcus neoformans from the respiratory tract

Cryptococcus neoformans was isolated from 65 patients: 11 had meningitis, 11 had disseminated cryptococcosis without meningitis, and 43 had C neoformans isolated from the respiratory tract. Predisposing conditions and the diagnostic value of cultures from various sites and of the latex agglutination test on cerebrospinal fluid and serum are analyzed for patients with extrapulmonary disease. Nine patients had pleural effusions; the effusion was cultured in six and yielded C neoformans in four. None of 11 deaths among 43 patients with respiratory tract isolates could be attributed to cryptococosis. The 32 survivors were nor treated with antifungal agents. Twenty-six of 43 patients with respiratory isolates had various bronchopulmonary disorders, with chronic obstructive pulmonary diseases and asthma the most common (28 percent). Seven of 28 patients (25 percent) with roentgenographically detected lung lesions had carcinoma of the lung. Roentgenographic evidence of a lung lesion and C neoformans grown from the respiratory tract warrant a further search for carcinoma of the lung.

Bactericidal activity of combinations of penicillin or clindamycin with gentamicin or streptomycin against species of viridans streptococci

Checkerboard bactericidal studies were performed with two strains each of Streptococcus mitis, S. salivarius, and S. sanguis, and the results were analyzed by the use of isobolograms. Synergy between penicillin and streptomycin or gentamicin was demonstrated with four strains, representing two of S. salivarius, one of S. sanguis, and one of S. mitis; the remainder were either too susceptible or too resistant to be analyzed. Clindamycin with streptomycin or gentamicin acted synergistically with three strains, representing two of S. sanguis and one of S. salivarius; the remainder were either too susceptible or too resistant to be analyzed.