Common Pathogen In Patients Research Articles

Nosocomial bacterial meningitis in adults: a prospective series of 50 cases

In order to evaluate characteristics of nosocomial meningitis in adults, we performed a prospective cohort study of 50 episodes of nosocomial bacterial meningitis. These cases were confirmed by culture of cerebrospinal fluid (CSF) in patients aged >16 years. Classic symptoms of bacterial meningitis (headache, neck stiffness and fever) were present in >70% of the episodes, although only a minority (41%) presented with impairment of consciousness. Underlying conditions, such as a history of neurosurgery, recent head injury, CSF leakage or a distant focus of infection, were present in 94% of the episodes. Staphylococcus aureus was the most common pathogen in patients with a history of neurosurgery, causing 10 of 32 episodes (31%). Patients with a distant focus of infection, such as otitis, sinusitis or pneumonia were more likely to have meningitis due to Streptococcus pneumoniae than patients without [six of nine episodes (67%) vs seven of 41 (17%); P=0.01]. Complications occurred in 50% of the episodes and 16% of the patients died. Our study confirms that adults with nosocomial meningitis are a distinct patient group with specific bacterial pathogens, as compared to those with community-acquired bacterial meningitis. Underlying conditions, especially a history of neurosurgery or a distant focus of infection, were present in the large majority of patients, and mortality and morbidity rates were high.

Purulent pericarditis due to co-infection with Streptococcus pneumoniae and Mycobacterium tuberculosisin a patient with features of advanced HIV infection

BackgroundBoth Mycobacterium tuberculosis and Streptococcus pneumoniae are common pathogens in patients with HIV infection.Case PresentationWe present an unusual case of purulent pericarditis resulting in cardiac tamponade due to infection with both organisms. We highlight the re-emergence of pneumococcal pericarditis in the HIV era and describe the pitfalls and challenges in the diagnosis of this condition.ConclusionClinicians working in HIV endemic areas need to consider dual infection with these organisms in patients who respond inadequately to either antibiotics or anti-tuberculous therapy alone.

Multiloculated Pyogenic Brain Abscess: Experience in 25 Patients

To report our experience in treating multiloculated pyogenic brain abscess and determine whether there are differences in the bacteriology, predisposing factors, treatment choices, and outcomes between multiloculated and uniloculated brain abscesses. We studied clinical data collected during a 16-year period from 124 patients with pyogenic brain abscess, including 25 cases of multiloculated abscess. The incidence of multiloculated brain abscess was 20%. In these 25 patients, hematogenous spread from a remote infectious focus was the most common cause of infection, as it was for the cases of uniloculated abscess. Headache and hemiparesis were the most common symptoms in patients with multiloculated abscess. In patients with uniloculated abscess, fever was the most common symptom. Viridans streptococci were the most commonly isolated pathogens. Bacteroides fragilis was the most common anaerobe in multiloculated abscess, and aerobic gram-negative bacilli were the most common pathogens in patients with uniloculated abscess. Of the patients with multiloculated abscess, 21 were treated surgically and 4 were treated with antibiotics only. Overall, eight patients (38%) needed another operation because of abscess recurrence after the initial operation. In uniloculated abscess, the rate of abscess recurrence after initial surgery was 13.1%. Mortality was 16% in multiloculated abscess and 17.1% in uniloculated abscess. Multiloculated abscesses accounted for 20% of our patients with pyogenic brain abscess. Excision seems to be the more appropriate surgical choice in multiloculated abscess. Prognosis for patients with multiloculated abscess can be as good as that for patients with uniloculated abscess. However, clinicians must carefully monitor these patients because the possibility of recurrence after surgery is significantly higher in patients with multiloculated abscess than in those with uniloculated abscess.

Do agents used for epidural analgesia have antimicrobial properties?

Local anesthetics inhibit bacteria growth in culture although this effect diminishes as the concentration of the drug is reduced. The antimicrobial properties of opioids are unknown. This study was designed to determine the ability of lidocaine and bupivacaine, with or without fentanyl or sufentanil, to inhibit bacteria growth in culture at concentrations typically used to provide analgesia. Potential bacteria pathogens were cultured in agar media containing: agar alone, 2%, 1.5%, and 1% lidocaine, 0.5%, 0.25%, and 0.125% bupivacaine, 0.125% bupivacaine + fentanyl 2 mcgs/mL, 0.125% bupivacaine + sufentanil 0.3 mcgs/mL, and fentanyl 5 mcgs/mL, fentanyl 2 mcgs/mL or sufentanil 0.3 mcgs/mL. Organisms were deemed sensitive to the study agent if no growth was apparent after incubation for 24 hours. Both lidocaine and bupivacaine significantly reduced bacteria growth at all concentrations studied compared to the growth observed in agar alone (P < .0001). This growth inhibition diminished as the concentration of local anesthetic was reduced especially for certain bacteria species for example. Staphylococcus aureus (P < .0001). Neither fentanyl nor sufentanil inhibited any bacterial growth in culture. Since the growth in culture of common pathogens, especially S. aureus, is not inhibited as the concentration of local anesthetic is reduced, the local anesthetics tested are unlikely to help prevent epidural-catheter-related infection due to common pathogens. More study is necessary to determine if local anesthetics help prevent infection from less common pathogens in patients at increased risk for infectious complications.