Beyond the Local Basic Panel: Full CFTR Gene Analysis Identifies Novel CF Mutation Missed on Standard Testing in an Arabic Child

Comparison of refugee patients with cystic fibrosis and their counterpart children from Turkey during the war

Since the outbreak of the Syrian civil war in 2011, the population of Arab refugees in Turkey has rapidly increased. While cystic fibrosis (CF) is believed to be rare among Arabs, recent studies suggest it is underdiagnosed. This study aims to present the demographic, clinical, and genetic characteristics of CF patients among Arab refugees in Turkey. Additionally, a comparison is made between the findings in the National CF Registry 2021 in Turkey (NCFRT) and the refugee CF patient group. The study included refugee patients between the ages of 0 and 18 years who were diagnosed with CF and received ongoing care at pediatric pulmonology centers from March 2011 to March 2021. The study examined demographic information, age at diagnosis, age of diagnosis of patients through CF newborn screening (NBS), presenting symptoms, CF transmembrane conductance regulator (CFTR) mutation test results, sputum culture results, weight, height, and body mass index (BMI) z score. Their results were compared with the NCFRT results. The study included 14 pediatric pulmonology centers and 87 patients, consisting of 46 (52.9%) boys and 41 (47.1%) girls. All of the patients were Arab refugees, with 80 (92%) being Syrian. All the patients were diagnosed in Turkey. The median age at diagnosis of patients was 22.33 (interquartile range, 1-258) months. The median age of diagnosis of patients through NBS was 4.2 (interquartile range, 1-12) months. The median age of older patients, who were unable to be included in the NBS program, was 32.3 (interquartile range, 3-258) months. Parental consanguinity was observed in 52 (59.7%) patients. The mutation that was most frequently found was F508del, which accounted for 22.2% of the cases. It was present in 20 patients, constituting 32 out of the total 144 alleles. There was a large number of genetic variations. CFTR genotyping could not be conducted for 12 patients. These patients had high sweat tests, and their genetic mutations could not be determined due to a lack of data. Compared to NCFRT, refugee patients were diagnosed later, and long-term follow-up of refugee CF patients had significantly worse nutritional status and pseudomonas colonization.  Conclusion: Although refugee CF patients have equal access to NBS programs and CF medications as well as Turkish patients, the median age at diagnosis of patients, the median age of diagnosis of patients through NBS, their nutritional status, and Pseudomonas colonization were significantly worse than Turkish patients, which may be related to the difficulties of living in another country and poor living conditions. The high genetic heterogeneity and rare mutations detected in the refugee patient group compared to Turkish patients. Well-programmed NBS programs, thorough genetic studies, and the enhancement of living conditions for refugee patients in the countries they relocate to can have several advantages such as early detection and improved prognosis. What is Known: • Children who have chronic diseases are the group that is most affected by wars. • The outcome gets better with early diagnosis and treatment in patients with Cystic Fibrosis (CF). What is New: • Through the implementation of a newborn screening program, which has never been done in Syria previously, refugee patients, the majority of whom are Syrians were diagnosed with cystic fibrosis within a duration of 4 months. • Despite equal access to the newborn screening program and CF medications for both Turkish patients and refugee patients, the challenges of living in a foreign country have an impact on refugees.

A Unique Mutation in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Gene Causing Cystic Fibrosis in a Pakistani Child: A Case Highlighting the Need for More Awareness

Cystic fibrosis (CF) is a recessively inherited disease most commonly seen in Caucasians. The mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene are responsible for the condition, and to date, more than 2000 mutations have been published in the literature. The most common mutation worldwide is F508del. Here, we reported a five-year-old child who presented to the clinic with a chronic cough. Her newborn screening for CF was negative, including 139 mutation panels done in India. The sweat chloride test was positive, and CF gene sequencing was reported as c.2489dup p. (Glu831GLYFS *5) homozygotes mutation in the CFTR gene (Online Mendelian Inheritance in Man (OMIM) *602421). To the best of our knowledge, this gene was first described and published in the literature.