Faculty Bibliography

We report on a former 28-week gestation neonate with persistent methicillin-resistant Staphylococcus aureus (MRSA) endocarditis, with a heterozygous Factor V Leiden mutation. The neonate became clinically ill after 1 week of life, with positive blood cultures for MRSA. Echocardiography revealed large thrombi in the inferior vena cava and right atrium. Bacteremia persisted despite removal of umbilical arterial and venous catheters and empiric administration of therapeutic doses of vancomycin (minimum inhibitory concentration [MIC] 2 mg/L) and ceftazidime. To narrow therapy, ceftazidime was discontinued, while gentamicin and rifampin were added. Cultures remained positive and, therefore, linezolid was added, and subsequent blood cultures became negative. Since prolonged linezolid use of 2 weeks or longer carries potential adverse effects, antibiotics were changed to daptomycin, which is bactericidal and recommended for treatment of invasive MRSA infections when vancomycin MICs are ≥2 mg/L to minimize vancomycin treatment failure. Enoxaparin was initiated, with anti-Xa assay monitoring. A workup for thrombophilia revealed heterozygous Factor V Leiden mutation. Serial echocardiograms demonstrated decreasing size of the thrombi, which were no longer visualized at 2 months of age. Creatinine kinase remained normal. The infant had no seizures on daptomycin. The management of persistent MRSA bacteremia in neonates associated with a large thrombus poses a unique challenge due to the long duration of treatment. To our knowledge, this is the first case of prolonged and safe daptomycin and enoxaparin use in a preterm neonate. Daptomycin may be considered in cases of clinical failure with vancomycin when a lengthy treatment course is contemplated.

Objective: The aim of this study was to examine the prevalence of bandemia in confirmed respiratory viral infections in febrile infants and children presenting to the emergency department. Methods: An observational retrospective study from January 1, 2016, through December 31, 2016, was conducted in patients between the ages of ≥ 1 month and ≤ 5 years presenting to the emergency room with fever and who had a complete blood cell count performed. Patients were separated into seven groups based on the type of respiratory viral infection. Inclusion criteria strictly counted children with viral infections and absence of clinical and laboratory evidence of a bacterial coinfection. Results: A total of 419 patients had a documented viral infection. A significant proportion of these children were found to have bandemia; children with adenovirus (17%), respiratory syncytial virus (RSV) (14.9%), human metapneumovirus (hMPV) (13%), and parainfluenza virus (7.9%) had the highest prevalence when the cutoff for bandemia was set at 10%. The prevalence increased to 35.3, 30.9, 40.3, and 15.8% for adenovirus, RSV, hMPV, and parainfluenza virus, respectively, when this cutoff was lowered further to 5%. Conclusion: Band neutrophils are detected frequently in confirmed respiratory viral infections particularly during early stages.