An Epidemiologic Study of Cystic Fibrosis in the Gaza Strip

Abstract

Objective: To determine the distribution, trend,, manifestations, prognosis and genetic determinants of cystic fibrosis (CF) diseases in the past ten years (2009-2019) in The Gaza strip (GS). Methods: Hospital based cross-sectional study and retrospective review of health care facilities records was conducted. This study was performed in all CF cases (150 cases) of five governorates of GS. The study population was one hundred and fifty CF cases, where 71% of them were males. Questionnaire and checklist were the tools of data collection about the personal, socio-demographic, health status of CF patients. In addition, Hemoglobin examination was obtained in all cases. Also Allele-specific PCR technique was employed to study eight CFTR mutation types for subgroup of CF cases (100 CF cases). The records of health care facilities which provide services to CF patients for the past ten years were reviewed retrospectively to determine the number of children who were diagnosed and confirmed as CF. Results: The average age of subjects was 70.6+44 months. About 93.3% of cases were of white colored skin. About one third of the population were from North Gaza, while 34.7% of them were from Gaza City, 22% of them were from Mid-zone, and 11.3% of them from South Governorates. about 88.7% of cases’ parents were first and second degree relatives. The results showed that the average of incidence of CF disease during the past ten years was 2.53 cases: 10,000 live births. Also the study showed increase in the prevalence of CF disease through the past ten years in GS, where the average of prevalence was 6.86 cases: 100,000 persons in 2009 and become 7.43 cases: 100,000 persons in 2019. About three quarter of CF cases were diagnosed during infantile period of their lives. Most of CF cases (91%) were diagnosed by both clinical manifestations and sweat tests. The most frequent respiratory manifestations among CF cases were recurrent chest infections, chronic cough with viscid sputum. While the most frequent gastrointestinal manifestations were recurrent gastroenteritis, abdominal colic and flatulence, and malabsorption. Also 86.7% of CF cases were anemic, where the average of hemoglobin among CF cases was 9.44+0.52 g/dl. The results of the study showed that the average of mortality rate due to CF among population under 15 years through the last ten years (2009-2019) was 0.52 case: 100,000 persons in population under 15 years. Allele-specific PCR technique was employed to study eight CFTR mutation types for the CF cases among subgroup of CF cases (100 CF cases). The results of mutation testing revealed that 62.5% of known mutation-CF cases have at least single allele of F508. Moreover 12.5% of known mutation-CF cases were of homo 3120+1kb CFTR mutation. Also 14.07% of known mutation-CF cases were of homo N1303k CFTR mutation, homo G85E CFTR mutation, and homo 3120del 18.6kb CFTR mutation equally. According to CFTR mutations about half of CF cases were belonging to class II CF. Conclusion: The incidence and prevalence rates of CF in the GS were around the rates of Caucasian Western Europe populations, where the average prevalence of CF disease through the last ten years in Gaza strip was 7.52 cases per 100,000 population. The average annual mortality rate among those less than 15 years was 0.52 case per 100,000. About two thirds of known mutation of CF cases have at least a single allele of DF508, which is considered of severe type of CFTR mutations. Also half of the cases belong to class II of CF disease (severe form of disease). Recommendations: the main recommendation of the current study was the importance of establishing a reliable diagnosis of CF using a properly conducted sweat test. In addition, diagnostic radiology, and laboratory facilities for sputum culture and pulmonary function tests are important for both the initial diagnosis and the diagnosis of complications. Funding Statement: This research did not receive any specific grant from funding agencies in the public, commercial or not-for-profit sectors. Declaration of Interests: The authors declare no conflicts of interest regarding the publication of this paper. Ethics Approval Statement: An official letter of approval to conduct the study was obtained from the Palestinian MOH and Helsinki Committee in the GS. The researcher signed a contract with (CFFC) Laboratory for conducting the sweat tests and analysis of blood samples for CBC. Furthermore, the researcher signed a contract with the Islamic University of Gaza main laboratory for doing the molecular and genotype testing by PCR.