Abstract:
This report synthesizes infectious disease literature and clinical trial data from the first half of December 2007. Key findings span the management of HIV-associated complications, emerging arboviral threats, and comparative efficacy in Hepatitis B therapies. Notable data includes the efficacy of Tesamorelin in reducing visceral adipose tissue in HIV patients and the superiority of Telbivudine over Adefovir in chronic Hepatitis B. The summary also addresses the limitations of antibiotics in treating acute sinusitis and uncomplicated skin abscesses, the increasing prevalence of multi-drug resistant (MDR) organisms such as MRSA and XDR-TB, and the correlation between recent respiratory infections and cardiovascular events. Clinical pearls regarding catheter-related bloodstream infections (CRBSI) and the role of steroids in bacterial meningitis are also highlighted.
Clinical Review: Infectious Disease Literature (Dec 1β15, 2007)
0:02:10 HIV Provider Fatalism: A survey of 316 HIV providers indicates that clinician fatalism regarding patient outcomes correlates with reduced frequency of risk-reduction counseling and preventative care.
0:03:03 HIV Lipodystrophy and Tesamorelin: Results from a 26-week study of Tesamorelin (a growth hormone-releasing factor) show a 15% reduction in visceral adipose tissue and a mean triglyceride decrease of 50 mg/dL without adversely affecting glucose control.
0:04:19 HIV-Related Stroke: Clinical data suggests a mean age of 33.4 for HIV-associated strokes, with 37% of cases occurring during an intercurrent opportunistic infection. Vasculopathy is identified as a primary etiology.
0:05:22 CNS HIV Viral Load: Lopinavir/ritonavir monotherapy was shown to reduce HIV RNA in the cerebrospinal fluid (CSF) by an average of 1.44 logs, suggesting utility in managing CNS-specific viral replication.
0:06:15 Chikungunya Mutation: A single mutation has enabled the Chikungunya virus to utilize the Asian Tiger mosquito (Aedes albopictus) as a vector, significantly expanding its potential geographic range into Europe and the Americas.
0:07:32 Hepatitis B (Telbivudine vs. Adefovir): At 52 weeks, Telbivudine demonstrated superior DNA suppression (6.3 log reduction vs. 4.97 log) and higher rates of E-antigen loss compared to Adefovir. Resistance was noted at the M204I mutation.
0:09:07 Herpes Zoster in Transplant Recipients: Incidence of Zoster in organ transplant patients is recorded at 28 per 1,000 person-years. Risk factors include advancing age (1.5x increase per decade) and seronegativity for VZV.
0:10:15 MRSA Abscess Management: In a randomized trial of placebo vs. Cephalexin for MRSA-predominant boils, cure rates were comparable (90% vs. 84% respectively), reinforcing that surgical incision and drainage (I&D) is the primary therapeutic intervention.
0:12:01 MRSA Colonization Dynamics: Nasal screening is a poor predictor of infection; one-third of MRSA-infected patients do not exhibit nasal colonization. Colonization is also associated with higher rates of multi-drug resistance in other organisms.
0:13:46 Vancomycin and Daptomycin Resistance: Prior exposure to Vancomycin within 30 days is associated with increased MICs and reduced killing kinetics in subsequent MRSA bacteremia. Daptomycin resistance is similarly linked to prior use during therapy for right-sided endocarditis.
0:16:02 Acute Sinusitis Efficacy Trial: A double-blind, placebo-controlled trial found no clinical difference between Amoxicillin, nasal steroids, or placebo in the treatment of acute non-recurrent sinusitis.
0:18:20 Steroids in Bacterial Meningitis: Studies in Vietnam and Africa indicate that Dexamethasone does not improve outcomes in adults with meningitis unless the disease is microbiologically proven. In HIV-heavy populations, steroids did not alter morbidity or mortality.
0:21:03 Nocturnal Cough in Pediatrics: Honey was found superior to no treatment for nighttime cough in children; however, it showed no statistically significant difference when compared to honey-flavored Dextromethorphan.
0:22:18 Post-Infection MI and Stroke Risk: A database of 2 million people shows the risk of myocardial infarction (MI) or stroke doubles within one year following a pneumonia diagnosis, likely due to prothrombotic endothelial cell activation.
0:24:01 Vibrio vulnificus Necrotizing Fasciitis: Surgical intervention (fasciotomy) within 24 hours of presentation significantly improves survival. High-risk groups include those with liver disease, diabetes, and recent exposure to seawater or raw seafood.
0:25:01 Paracoccidioidomycosis Treatment: Voriconazole (200mg BID) was found clinically equivalent to Itraconazole (100mg BID) for the treatment of South American blastomycosis.
0:26:00 Femoral Catheter-Related Infections: Femoral venous access sites exhibit significantly higher rates of Gram-negative rods (38% vs. 8%) and Yeast (17% vs. 2%) compared to other catheterization sites.
0:28:11 Virulence of Resistant Strains: Research on Pseudomonas aeruginosa bacteremia suggests that multiple resistance mechanisms do not result in decreased fitness or virulence.
0:29:19 PPIs and Enteric Infections: Proton Pump Inhibitor (PPI) use is associated with a dose-dependent increase in the risk of Salmonella and Campylobacter gastroenteritis.
0:33:30 XDR-TB and South Africa: Extensively drug-resistant TB (XDR-TB) is spreading rapidly in HIV-susceptible populations in South Africa, driven by a lack of susceptibility testing and directly observed therapy (DOTS) failures.
0:35:22 Aminoglycoside Monotherapy: A systemic review suggests restricting aminoglycoside monotherapy to urinary tract infections (UTIs) due to higher failure rates in non-UTI clinical settings.