Postnatal cytomegalovirus infection and pulmonary vascular disease in extremely premature infants: A case series.

BACKGROUND: Pulmonary vascular disease (PVD) is a major determinant of both morbidity and mortality in extremely low birth weight infants. It is biologically plausible that postnatal cytomegalovirus (pCMV) infection may lead to PVD in premature infants secondary to pneumonitis or via derangement of pulmonary vascular development directly through endothelial dysfunction. Uncertainty remains, however, regarding thresholds for intervention in premature infants with cardiorespiratory instability and presumed CMV infection likely secondary to the limited understanding of the natural history of the disease. METHODS/RESULTS: We describe four cases of premature infants with clinical and echocardiography features of PVD, in the setting of postnatally acquired CMV. All patients had atypical PVD trajectories, refractory to vasodilator treatment, which improved after initiation of CMV treatment. CONCLUSION: We highlight the need to consider postnatally acquired CMV infection in patients with PVD non-responsive to standard pulmonary vasodilator therapies or disease severity which is out of proportion of the usual clinical trajectory. Treatment of extremely premature infants with CMV-associated PVD may have positive impact on cardiorespiratory health, although duration of therapy remains uncertain.

Lack of association between potential prothrombotic genetic risk factors and arterial and venous thrombosis.

Recent studies have shown an association between thrombosis and factor VII (FVII), tissue factor (TF), and angiotensin-converting enzyme (ACE). This suggests that individuals with FVII-402 G/A, FVII-401 G/T, TF+5466 A/G, and ACE-287 insertion/deletion (I/D) polymorphisms present an increased risk of venous thrombosis, heart disease, and ischemic stroke compared with controls. In this study, we investigated the frequencies of these polymorphisms and their association with arterial and venous thrombosis. For the FVII-402 G/A polymorphism, there were 57.3% heterozygote (HT) genotypes and 8.3% homozygote (HM) genotypes in the patients, and 45.2% HT genotypes and 15.4% HM genotypes in the controls. For the FVII-401 G/T polymorphism, there were 37.5% HT genotypes and 3.1% HM genotypes in the patients, and 32.7% HT genotypes and 4.8% HM genotypes in the controls. The polymorphism TF+5466 A/G was not found in any of the samples analyzed. For the ACE-287 I/D polymorphism, there were 43 (40.6%) HT genotypes and 63 (59.4%) HM genotypes in the controls and 28 (45.2%) HT genotypes and 34 (54.8%) HM genotypes in the patients. No significant difference was observed by comparing patients and controls. In this study, no association was found between the presence of the evaluated polymorphisms and the occurrence of thrombotic events.