Ganciclovir in Congenital Cytomegalovirus Infection Associated with Pulmonary Hypertension

Abstract

of oral sildenafil therapy. Conclusions: Increased arterial inflow is the primary hemodynamic event in the development of penile erection. NO acts as a messenger molecule stimulating guanylate cyclase, and leading to the formation of cyclic guanosine monophosphate (cGMP). cGMP then acts through calcium-gated potassium channels to cause vascular smooth muscle relaxation. Phosphodiesterases (PDE) are an integral component of cyclic nucleotide signaling. PDE5 is found in high concentration within the smooth muscle of the pulmonary vasculature and corpus cavernosum. Therefore, PDE5 inhibitors such as sildenafil. known to improve erectile dysfunction. have also been used in the treatment of PPHN. We hypothesize that the NO administered in the first case and the oral sildenafil given in the second case resulted in a high flow state leading to prolonged penile erection. By the proposed mechanism, hypoxia and acidosis would not occur. The clinical course of PPE of the newborn differs greatly from that of priapism. In most instances, spontaneous detumescence occurs, and therefore observation rather than surgical therapy is advocated.