Abstract

INTRODUCTION

Several hundreds of cystic fibrosis transmembrane conductance regulator (CFTR) variants have been reported, it is not known whether they are causing CF or not. The most interesting finding about the different patterns was CFTR genes carrying the M470 or the V470 allele. In this study, we aimed to investigate the clinical importance of M470V mutation in Antiochia region.

METHODS

A case control study was consisted of 145 children who were undergone CF gene study because of recurrent respiratory tract infections, growth failure, chronic diarrhea and constipation. The parameters of patients with positive mutation compared with negative ones (gender, age, height, weight, annual number of upper and lower respiratory tract infections, parental consanguinity, sibling death, findings of clinical and laboratory).

RESULTS

In 63 of 145 patients (43.4%), heterozygous mutation, in 16 (11%) homozygous mutation was detected. All of them (mutation group) had M470V mutation. The sweat test results of all patients were within the normal limits. Mean age of those patients were 41.21±39.8 ( min: 6 max: 192 ) months and 30 (38%) were girls. Of the patients with mutation 17.7(32%) had a familial history of cystic fibrosis, 2 had sibling death history. In mutation group, only annual number of infections, skin dryness, loss of weight, level of IgG and IgM were significantly higher (p<0.05).

DISCUSSION AND CONCLUSION

It was concluded that in M470V positive cases, the disease may cause clinical symptoms without affecting sweat test results, with less gastrointestinal but more respiratory symptoms, causing a more prominent loss of weight.