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Burke A Cunha

Publications and source records attributed to Burke A Cunha.

At least 19 recordsLinked to original sources
PubMed2006

A cluster of nosocomial herpes simplex virus type 1 pneumonia in a medical intensive care unit.

We report a cluster of 3 cases of nosocomial herpes simplex virus type 1 (HSV-1) pneumonia occurring in close temporal and physical proximity during a 1-week period, which suggested a common source. HSV-1 nosocomial pneumonia occurs in immunocompetent intubated patients and presents as otherwise unexplained profound and/or prolonged hypoxemia (decreased F(IO2), increased P(O2), and decreased A-a gradient) and "failure to wean." The diagnosis of HSV-1 pneumonia is determined by demonstration of characteristic cytopathologic findings (Cowdry type A inclusion bodies) in distal respiratory epithelial cells from bronchoscopic specimens. Acyclovir therapy results in rapid improvement and ability to wean.

Acyclovir↗
PubMed2006

Lack of value of repeat stool testing for Clostridium difficile toxin.

Twenty years ago, Clostridium difficile was first established as a cause of pseudomembranous colitis and antibiotic-associated diarrhea.C. difficile diarrhea is a widely recognized problem in the inpatient setting, with potentially significant morbidity and mortality. Antibiotics, and some chemotherapy agents, can potentially cause C. difficile colitis/diarrhea. The most commonly implicated agents are ampicillin, clindamycin, and cephalosporins. Diarrhea during antibiotic therapy is common and may be caused by C. difficile. Testing for C. difficile differentiates diarrheas into C. difficile positive and C. difficile negative. C. difficile can be carried asymptomatically as normal gastrointestinal flora, and in adults who have received antibiotic therapy, carrier states can be as high as 46%. Hospitalized patients are often colonized with C. difficile. C. difficile produces 3 virulence factors: an enterotoxin (toxin A), a cytotoxin (toxin B), and a substance to inhibit bowel motility. Different tests can be used to detect these toxins. The most widely used test is the enzyme immunoassay (EIA) for toxin A, toxin B, or both. The EIA C. difficile toxin assay has sensitivity and specificity ranges of 50% to 90% and 70% to 95%, respectively. Diagnostically, C. difficile cell culture cytotoxin assay remains the gold standard with sensitivity and specificity of 93% and 89%, respectively. Because of lack of confidence of the EIA for C. difficile, some clinicians assume an initial negative result may represent a false-negative test, and repeat testing is often done. We evaluated the value of repeat stool testing for C. difficile toxin A and B by EIA in inpatients with nosocomial diarrhea on antibiotics.

Anti-Bacterial Agents↗
PubMed2006

Antibiotic selection in the penicillin-allergic patient.

Clinicians should be familiar with which antibiotics are safe to use for different types of penicillin-allergic reactions. Clinically, it is convenient to divide patients with penicillin allergy into three categories: those with unknown or possible reactions to penicillin, those with a drug fever or rash, and those with hives or anaphylactic reactions. Beta-lactam antibiotics may be used safely for patients with unknown/possible penicillin allergy and drug fever or rash. Penicillins or beta-lactams should not be used for patients with hives or anaphylactic reactions. For all patients, clinicians should consider antimicrobial therapy with an antibiotic that does not cross-react with penicillins or beta-lactams. This article reviews how clinicians should select antimicrobials in penicillin-allergic patients.

Anaphylaxis↗
PubMed2006

New uses for older antibiotics: nitrofurantoin, amikacin, colistin, polymyxin B, doxycycline, and minocycline revisited.

Nitrofurantoin, amikacin, colistin, polymyxin B, doxycycline, and minocycline are antibiotics with proven effectiveness against selected pathogens. These antibiotics have not developed resistance over time. As "low-resistance potential antibiotics" that are effective against an increasing number of infections due to resistant gram-positive or gram-negative pathogens, these antimicrobials remain an important part of the antibiotic armamentarium. They will be used increasingly in the future, as highly resistant organisms continue to be important clinically and therapeutic options remain limited.

Amikacin↗
PubMed2006

Antimicrobial therapy of multidrug-resistant Streptococcus pneumoniae, vancomycin-resistant enterococci, and methicillin-resistant Staphylococcus aureus.

Antibiotic resistance among pneumococci, enterococci, and staphylococci has become increasingly important in recent decades. Clinicians should be familiar with the nuances of antibiotic susceptibility testing and interpretation in selecting antibiotics for these infections. The clinical significance of penicillin-resistant Streptococcus pneumoniae, macrolide-resistant S pneumoniae, and multidrug-resistant S pneumoniae is discussed. The clinical spectrum and therapeutic approach to Enterococcus faecalis (i.e., vancomycin-sensitive enterococci) and E faecium (i.e., vancomycin-resistant enterococci) are discussed. Differences in therapeutic approach between methicillin-sensitive Staphylococcus aureus and methicillin-resistant S aureus (MRSA) infections are reviewed. Differences between in vitro susceptibility testing and in vivo effectiveness of antibiotics for hospital-acquired MRSA (HA-MRSA) are described. Finally, the clinical features of infection and therapy of HA-MRSA and community-acquired MRSA (CA-MRSA) infections are compared.

Anti-Infective Agents↗
PubMed2006

Oral antibiotic therapy of serious systemic infections.

Traditionally, antibiotics have been administered intravenously (IV) for serious systemic infections. As more potent oral antibiotics were introduced, and their pharmacokinetic aspects studied, orally administered antibiotics have been increasingly used for serious systemic infections. Antibiotics ideal for oral administration are those that have the appropriate spectrum, high degree of activity against the presumed or known pathogen, and have good bioavailability. Oral antibiotics with high bioavailability, that is > or = 90% absorbed, achieve serum/tissue concentrations comparable to IV administered antibiotics at the same dose. The popularity of "IV to PO switch therapy" is possible because of the availability of many potent oral antibiotics with high bioavailability. Initial IV therapy is appropriate in patients who are in shock/have impaired intestinal absorption, but after clinical defervescence, completion of therapy should be accomplished with oral antibiotics. As experience with "IV to PO switch therapy" has accumulated, confidence in oral antimicrobics for therapy of serious systemic infections has continued to increase. The trend in treating serious systemic infections entirely with oral antimicrobial therapy will continue, and is clearly the wave of the future.

Administration, Oral↗
PubMed2006

Ventilator-associated pneumonia: monotherapy is optimal if chosen wisely.

Traditionally, ventilator-associated pneumonia (VAP) has been treated either with double drug therapy or with monotherapy. Double drug therapy has been used to increase spectrum, for possible synergy, and to decrease the emergence of resistance. VAP therapy should be directed primarily against Pseudomonas aeruginosa, which also provides aerobic Gram-negative coverage, the usual pathogens in VAP. The potent anti-P. aeruginosa antibiotics available today have sufficient activity that double drug coverage is unnecessary. Double drug therapy does not decrease resistance if a 'high resistance potential' antibiotic is used in the combination. The study by Damas and colleagues in this issue of Critical Care supports monotherapy for VAP. Optimal therapy for VAP involves selecting a potent anti-P. aeruginosa antibiotic with a 'low resistance potential' that minimizes drug-drug interactions, minimizes resistance, and is cost effective. Monotherapy of VAP should be the standard of care.

Anti-Bacterial Agents↗