Inducible and Acquired Clarithromycin Resistance in the Mycobacterium abscessus Complex

Clarithromycin was considered the cornerstone for the treatment of Mycobacterium abscessus complex infections. Genetic resistance mechanisms have been described and many experts propose amikacin as an alternative. Nevertheless, clarithromycin has several advantages; therefore, it is necessary to identify the non-functional erm(41) allele to determine the most suitable treatment. The aims of this study were to characterize the molecular mechanisms of clarithromycin resistance in a collection of Mycobacterium abscessus complex isolates and to verify the relationship between these mechanisms and the antibiogram. Clinical isolates of M. abscessus complex (n = 22) from 16 patients were identified using four housekeeping genes (rpoB, secA1, sodA and hsp65), and their genetic resistance was characterized by studying erm(41) and rrl genes. Nine strains were recovered from the clinical isolates and subjected to E-test and microdilution clarithromycin susceptibility tests, with readings at 3, 7 and 14 days. We classified 11/16 (68.8%) M. abscessus subsp. abscessus, 4/16 (25.0%) M. abscessus subsp. bolletii, and 1/16 (6.3%) M. abscessus subsp. massiliense. T28 erm(41) allele was observed in 8 Mycobacterium abscessus subps. abscessus and 3 Mycobacterium abscessus subsp. bolletii. One strain of M. abscessus subsp. bolletii had an erm(41) gene truncated and was susceptible to clarithromycin. No mutations were observed in rrl gene first isolates. In three patients, follow-up of initial rrl wild-type strains showed acquired resistance. Most clinical isolates of M. abscessus complex had inducible resistance to clarithromycin and total absence of constitutive resistance. Our findings showed that the acquisition of resistance mutations in rrl gene was associated with functional and non-functional erm(41) gene. Caution is needed when using erm(41) sequencing alone to identify M. abscessus subspecies. This study reports an acquired mutation at position 2057 of rrl gene, conferring medium-low clarithromycin constitutive resistance

Characteristics and outcome of spontaneous bacterial meningitis in patients with diabetes mellitus

Studies on bacterial meningitis in diabetics patients versus non-diabetics are scarce. In patients with diabetes, bacterial meningitis may have a different presentation, etiology and course. We analyzed and compared the characteristics and outcome of spontaneous BM in adult patients with and without diabetes mellitus (DM). We performed a single-center, prospective observational cohort study, conducted between 1982 and 2017, in a tertiary university hospital in Barcelona (Spain). The primary outcome measure was in-hospital mortality. We evaluated 715 episodes of bacterial meningitis; 106 patients (15%) had diabetes mellitus. Patients with diabetes were older (median 67 [IQR 17] vs 49 [IQR 40] years, p < 0.001) and more often had a Charlson comorbidity score of ≥3 (40% vs 15%, p < 0.001). Neck stiffness (56% vs 75%, p < 0.001), headache (41% vs 78%) p < 0.001), nausea and/or vomiting (32% vs 56% p < 0.001), and rash (12% vs 26%, p = 0.007) were less frequent in diabetics, whereas altered mental status was more common. Streptococcus pneumoniae and Listeria meningitis were the most common etiologic agents (24 and 18%, respectively). Listeria was more frequent (18% vs. 10%, p = 0.033), whereas meningococcal meningitis was less frequent (10% vs 32%, p < 0.001). Overall mortality was higher in patients with diabetes (26% vs 16%, p = 0.025) concerning non-diabetics. Patients with bacterial meningitis and diabetes mellitus are older, have more comorbidities, and higher mortality. S. pneumoniae and L. monocytogenes are the predominant pathogens, Listeria being more common, whereas Neisseria meningitidis is significantly less frequent than in non-diabetics

Spontaneous gram-negative bacillary meningitis in adult patients : characteristics and outcome

Background: Spontaneous meningitis caused by gram-negative bacilli in adult patients is uncommon and poorly characterized. Our objective is to describe and compare the characteristics and the outcome of adult patients with spontaneous gram-negative bacilli meningitis (GNBM) and spontaneous meningitis due to other pathogens. Methods: Prospective single hospital-based observational cohort study conducted between 1982 and 2006 in a university tertiary hospital in Barcelona (Spain). The Main Outcome Measure: In-hospital mortality. Results: Gram-negative bacilli meningitis was diagnosed in 40 (7%) of 544 episodes of spontaneous acute bacterial meningitis. The most common pathogens were Escherichia coli and Pseudomonas species. On admission, characteristics associated with spontaneous gram-negative bacilli meningitis by multivariate modeling were advanced age, history of cancer, nosocomial acquisition of infection, urinary tract infection as distant focus of infection, absence of rash, hypotension, and a high cerebrospinal fluid white-cell count. Nine (23%) episodes were acquired in the hospital and they were most commonly caused by Pseudomonas. The in-hospital mortality rate was 53%. The mortality rate was higher among patients with Gram-negative bacillary meningitis than among those with other bacterial meningitis and their risk of death was twenty times higher than among patients infected with Neisseria meningitidis (odds ratio 20.47; 95% confidence interval 4.03-103.93; p<0.001). Conclusions: Gram-negative bacilli cause 9% of spontaneous bacterial meningitis of known etiology in adults. Characteristics associated with GNBM include advanced age, history of cancer, nosocomial acquisition, and urinary tract infection as distant focus of infection. The mortality rate is higher among patients with gram-negative bacillary meningitis than among those with other bacterial meningitides

Characteristics and outcome of spontaneous bacterial meningitis in patients with cancer compared to patients without cancer

Supplemental Digital Content is available in the text In cancer patients, who are frequently immunocompromised, bacterial meningitis (BM) can be a severe complication, with a different presentation, etiology, and course, compared to patients without cancer. Our objective is to compare the characteristics and outcomes of BM in patients with and without cancer. A single-center, prospective observational cohort study, conducted between 1982 and 2012, in a tertiary university hospital in Barcelona (Spain). The main outcome measure is in-hospital mortality. We evaluated 659 episodes of BM; 97 (15%) had active cancer. Patients with malignancies were older (median 63 (interquartile range [IQR] 24) vs 52 [IQR 42] years, P < .001) and more often had a Charlson comorbidity score of ≥3 (51% vs 11%, P < .001). The classic meningitis triad (35% vs 50%, P = .05), fever (91% vs 96%, P = .03), neck stiffness (58% vs 78%, P < .001), headache (63% vs 77%) P = .003), and rash (7% vs 30%, P < .001) were less frequent. There was a longer interval between admission and antibiotic therapy (median 5 [IQR 14] vs 3 [IQR 6] hours, P < .001). Listeria meningitis was the commonest cause of BM (29%) and was more frequent in cancer than noncancer (8%, P < .001) patients, whereas meningococcal meningitis was much less frequent (4% vs 36%, P < .001). Overall mortality was higher in patients with cancer (31% vs 16%, P < .001), although cancer was not associated with an unfavorable outcome in the multivariate analysis (odds ratio 1.825, P = .07). Patients with meningitis and cancer are older and have more subtle clinical manifestations than patients without cancer. Listeria monocytogenes is the predominant pathogen and mortality is higher in cancer patients

Moisturizing body milk as a reservoir of Burkholderia cepacia : outbreak of nosocomial infection in a multidisciplinary intensive care unit

Background: An outbreak of severe nosocomial Burkholderia cepacia infections in patients admitted to intensive care unit (ICU), including investigation of the reservoir, is described. Methods: Over a period of 18 days, isolates of Burkholderia cepacia were recovered from different biological samples from five patients who were admitted to a multidisciplinary 18-bed intensive care unit. Isolation of B. cepacia was associated with bacteraemia in three cases, lower respiratory tract infection in one and urinary tract infection in one. Contact isolation measures were instituted; new samples from the index patients and adjacent patients were collected; and samples of antiseptics, eau de Cologne and moisturizing body milk available in treatment carts at that time were collected and cultured. Results: B. cepacia was isolated from three samples of the moisturizing body milk that had been applied to the patients. Three new hermetically closed units, from three different batches, were sent for culture; two of these were positive as well. All strains recovered from environmental and biological samples were identified as belonging to the same clone by pulsed-field gel electrophoresis. The cream was withdrawn from all hospitalization units and no new cases of B. cepacia infection developed. Conclusion: Moisturizing body milk is a potential source of infection. In severely ill patients, the presence of bacteria in cosmetic products, even within accepted limits, may lead to severe life-threatening infections

Spontaneous gram-negative bacillary meningitis in adult patients : characteristics and outcome

Background: Spontaneous meningitis caused by gram-negative bacilli in adult patients is uncommon and poorly characterized. Our objective is to describe and compare the characteristics and the outcome of adult patients with spontaneous gram-negative bacilli meningitis (GNBM) and spontaneous meningitis due to other pathogens. Methods: Prospective single hospital-based observational cohort study conducted between 1982 and 2006 in a university tertiary hospital in Barcelona (Spain). The Main Outcome Measure: In-hospital mortality. Results: Gram-negative bacilli meningitis was diagnosed in 40 (7%) of 544 episodes of spontaneous acute bacterial meningitis. The most common pathogens were Escherichia coli and Pseudomonas species. On admission, characteristics associated with spontaneous gram-negative bacilli meningitis by multivariate modeling were advanced age, history of cancer, nosocomial acquisition of infection, urinary tract infection as distant focus of infection, absence of rash, hypotension, and a high cerebrospinal fluid white-cell count. Nine (23%) episodes were acquired in the hospital and they were most commonly caused by Pseudomonas. The in-hospital mortality rate was 53%. The mortality rate was higher among patients with Gram-negative bacillary meningitis than among those with other bacterial meningitis and their risk of death was twenty times higher than among patients infected with Neisseria meningitidis (odds ratio 20.47; 95% confidence interval 4.03-103.93; p<0.001). Conclusions: Gram-negative bacilli cause 9% of spontaneous bacterial meningitis of known etiology in adults. Characteristics associated with GNBM include advanced age, history of cancer, nosocomial acquisition, and urinary tract infection as distant focus of infection. The mortality rate is higher among patients with gram-negative bacillary meningitis than among those with other bacterial meningitides