Disinfection of Burkholderia cepacia complex from non-touch taps in a neonatal nursery

Burkholderia cepacia complex (Bcc) comprises nine closely related species or genomovars. It is an important causative agent of opportunistic infections and waterborne nosocomial infections. B. cepacia (formerly genomovar I) was identified from the blood culture of a baby in our neonatal unit (NU) in March 2005. B. cepacia was isolated four times from clinical specimens since the introduction of non-touch taps in the NU from 2000 to 2005 and only once from 1994 to 2000. Environmental samples were collected from the NU, including tap water from non-touch taps. Clinical and environmental isolates of Bcc were characterized using molecular identification and strain typing. A literature review was undertaken to delineate a method for eradication of Bcc. Several variations for hot water eradication of the organism from the taps were attempted. Genotyping and molecular analysis revealed that tap water isolates were B. cenocepacia which was a different species from the B. cepacia isolated from blood cultures of the neonate. However, B. cenocepacia has been known to cause nosocomial outbreaks and it was eventually eradicated from the NU by using repeated thermal shock (hot water at 65 degrees C for 10 min), changing taps and decolonizing sinks with hypochlorite. Molecular typing is useful in assisting the investigation of Bcc nosocomial infections.

Hyperoxia Depletes (6R)-5,6,7,8-Tetrahydrobiopterin Levels in the Neonatal Retina: Implications for Nitric Oxide Synthase Function in Retinopathy

Retinopathy of prematurity is a sight-threatening complication of premature birth caused by nitrooxidativeinsult to the developing retinal vasculature during therapeutic hyperoxia exposure and laterischemia-induced neovascularization on supplemental oxygen withdrawal. In the vasodegenerativephase, during hyperoxia, defective endothelial nitric oxide synthase (NOS) produces reactive oxygenand nitrogen free radicals rather than vasoprotective nitric oxide for unclear reasons. More important,NOS critically depends on the availability of the cofactor (6R)-5,6,7,8-tetrahydrobiopterin (BH4).Because BH4 synthesis is controlled enzymatically by GTP cyclohydrolase (GTPCH), we used GTPCHdepletedmice [hyperphenylalanaemia strain Q4 (hph1)] to investigate the impact of hyperoxia on BH4bioavailability and retinal vascular pathology in the neonate. Hyperoxia decreased BH4 in retinas,lungs, and aortas in all experimental groups, resulting in a dose-dependent decrease in NOS activityand, in the wild-type group, elevated NOS-derived superoxide. Retinal dopamine levels were similarlydiminished, consistent with the dependence of tyrosine hydroxylase on BH4. Despite greater depletionof BH4, the hphþ/ and hph1/ groups did not show exacerbated hyperoxia-induced vessel closure,but exhibited greater vascular protection and reduced progression to neovascular disease. This vasoprotectiveeffect was independent of enhanced circulating vascular endothelial growth factor (VEGF),which was reduced by hyperoxia, but Q5 to local ganglion cell layerederived VEGF. A constitutively higherlevel of VEGF expression associated with retinal development protects GTPCH-deficient neonates fromoxygen-induced vascular damage.

A high-value, low-cost bubble continuous positive airway pressure system for low-resource settings:technical assessment and initial case reports

Acute respiratory infections are the leading cause of global child mortality. In the developing world, nasal oxygen therapy is often the only treatment option for babies who are suffering from respiratory distress. Without the added pressure of bubble Continuous Positive Airway Pressure (bCPAP) which helps maintain alveoli open, babies struggle to breathe and can suffer serious complications, and frequently death. A stand-alone bCPAP device can cost $6,000, too expensive for most developing world hospitals. Here, we describe the design and technical evaluation of a new, rugged bCPAP system that can be made in small volume for a cost-of-goods of approximately $350. Moreover, because of its simple design--consumer-grade pumps, medical tubing, and regulators--it requires only the simple replacement of a <$1 diaphragm approximately every 2 years for maintenance. The low-cost bCPAP device delivers pressure and flow equivalent to those of a reference bCPAP system used in the developed world. We describe the initial clinical cases of a child with bronchiolitis and a neonate with respiratory distress who were treated successfully with the new bCPAP device.