Guillermo Pousada Fernández

Estudio de la repetición del pentanucleótido CCTTT en el gen de la sintasa inducible del óxido nítrico en pacientes con hipertensión arterial pulmonar

INTRODUCTION One of the pathways involved in pulmonary arterial hypertension (PAH) is the nitric oxide (NO) pathway. A polymorphism in the inducible NO synthase (NOS2) gene has been described, consisting of the CCTTT pentanucleotide repeat, which causes a reduction in NO production. The aim of this study was to determine if this polymorphism increases susceptibility to developing PAH. METHODS Sixty four patients with a diagnosis of PAH groupsi and iv and 50 healthy controls were compared. DNA genotyping of the samples for this polymorphism was performed using PCR. The distribution between both groups was compared and correlated with clinical and haemodynamic parameters and therapeutic response. RESULTS A significantly different distribution was observed in the number of repeats between patients and controls (P<.0001). When the samples were categorised by short forms (both alleles with less than 12repeats) and long forms (≥12 repeats), it was observed that the former had an almost 4-fold risk of developing PAH (odds ratio: 3.83; 95%CI: 1.19-12.32, P=.024). There were no differences between the most common types of PAH, either in therapeutic response or survival. There was no correlation between haemodynamic parameters and the number of repeats in the patients, and only a weak correlation with systolic PAH. CONCLUSIONS There are significant differences in the distribution of the NOS2 promotor CCTTT polymorphism between patients with PAH and the healthy population. A minor CCTTT pentanucleotide repeat in the NOS2 gene may increase the risk of developing PAH.

Estudio clínico y molecular de 4 casos de hipertensión pulmonar asociada a sarcoidosis

Sarcoidosis is a pleomorphic disease that can present with pulmonary hypertension (PH). What little information is available about the association of these two diseases comes mainly from small series of patients scheduled for transplant. We present 4 cases of mild pulmonary involvement in whom right catheterisation was performed and PH-specific therapy was administered. After obtaining written consent, a genetic study was performed that showed mutations in PH-related genes in 3 of the patients. This is the first study of its kind to yield genetic information for this type of PH.