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BACKGROUND: Cystic fibrosis (CF) occurs in populations in Saudi Arabia and the Gulf area. Approximately 2000 known variants have been identified for the CF transmembrane conductance regulator (CTFR) gene. Screening for ten of the most common variants can detect 80% of alleles. OBJECTIVE: Determine the pattern of CFTR variants in the CF population of Saudi Arabia. DESIGN: A retrospective, descriptive. SETTING: Tertiary care center. PATIENTS AND METHODS: We examined the medical records of 396 confirmed CF patients of all age groups that were positive for a CFTR variant from the period of 1 January 1998 to 1 December 2017. MAIN OUTCOME MEASURES: Zygosity, morbidity and mortality patterns of different types of CFTR variants. SAMPLE SIZE: 312 families that included 396 patients. RESULTS: Of 48 variants identified, 6 were novel, having not been described in the medical literature. A homozygous state was found in 283 families (90.7%) and compound heterozygosity in 23 (7.4%). Six families were heterozygous (1.9%). Median age (interquartile range) was 10.2 months (4.4 months to 5.7 years) at diagnosis and 9.7 (5.4-16.5) years at follow up. Of 396 patients, 378 patients (95.5%) survived and 18 (4.5%) died. The ten most common variants identified in descending frequency were: p.Gly473GlufsX54 in 98 alleles (16%), p.Ile1234Val in 66 alleles (11%), F508del in 64 alleles (11%), 711+1G>T in 62 alleles (10%), 3120+1G>A in 62 alleles (11%), p.His139Leuin 38 alleles (6.4%), p.Gln637Hisfs in 30 alleles (5.2%), p.Ser549Arg in 27 alleles (4.5%), p.Asn1303Lys in 14 alleles (2.3%), delExon19-21in 10 alleles (1.6%). This analysis identified 79.2% of our CFTR variants. CONCLUSION: CFTR mutational patterns in our CF population are characterized by a high allelic heterogeneity. The high prevalence of homozygous variants reflects the high level of consanguinity between parents. LIMITATIONS: Our CFTR screening reflected only about 80% of CF patients in Saudi Arabia. CONFLICT OF INTEREST: None.

A 19-years-old girl was referred for lung transplant due to end stage lung disease secondary to idiopathic bilateral bronchiectasis. Her routine pre lung transplant evaluation showed normal esophageal high-resolution manometry (HRM) and 24-hours impedance pH monitoring. Four weeks after the bilateral sequential lung transplantation (LTx), she developed dysphagia, chest pain and regurgitation, complicated by aspiration pneumonia. Repeated HRM showed Jackhammer esophagus, delayed gastric emptying and abnormal 24-hour pH impedance monitoring consistent with the diagnosis of gastroesophageal reflux disease. Twelve weeks after LTx, she was symptom free, HRM and 24-hour impedance pH monitoring returned to normal. To the best of our knowledge, this rare transient esophageal hypercontractility episode occurred after LTx and recovered without any specific treatment was never reported in literature. The etiopathogenesis of Jackhammer esophagus in general and LTx induced dysmotility in particular is discussed and reviewed.

Introduction: Cystic fibrosis (CF) has been reported before in Saudi Arabia and the Gulf area. It has been found that screening for 10 most common cystic fibrosis transmembrane conductance regulator (CFTR) mutations can detect 80% of positive CFTR cases. Objectives: To determine the geographic distribution of the most common CFTR variants in 5 regions of Saudi Arabia. Methodology: A retrospective chart review of all CFTR variants conducted from January 1, 1992 to December 1, 2017. Results: The ten most common CFTR mutations in the Saudi population were as follows: p.Gly473GlufsX54 (17%), p.Phe508del (12%), p.Ile1234Val (12%), 3120+1G > A (11%), 711+1G > T (9%), p.His139Leu (6%), p.Gln637Hisfs (5%), p.Ser549Arg (3%), p.N1303K (3%), and delExon19-21 (2%) along with other variants 79 (20%). In terms of the highest frequency, the c.2988+1G > A (3120+1G > A) variant was found in the eastern province (7.3%) of Saudi Arabia, the c.1418delG (p.Gly473GlufsX54) variant in the northern province (6.8%), the c.579+1G > T (711+1G > T) variant in the southern province (4.8%), the c.3700A > G (p.Ile1234Val) variant in the central province (4.8%), and c.1521_1523delCTT (p.Phe508del) variant in the western province (4.3%). Conclusion: The eastern and the northern provinces have the highest prevalence of CF, with the c.2988+1G > A (3120+1G > A) and c.1418delG (p.Gly473GlufsX54) variants showing the highest distribution in the Saudi CF population, which may reflect the effect of consanguinity within the same tribe. Proper family screening and counseling should be emphasized.

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