Investigation of Primary Ciliary Dyskinesia in Children with Bronchiectasis in Iran

Abstract

Background: Primary ciliary dyskinesia (PCD) is a rare genetic disorder with signs and symptoms of recurrent chronic sinusitis, otitis media, pneumonia, bronchiectasis, male infertility, and situs inversus. The diagnosis of PCD has always been one of the more challenging issues that is mostly made through screening tests. These include the saccharin test and measurements of exhaled and nasal nitric oxide (NO) level, transmission electron microscopy (TEM) for evaluating ultrastructure of the cilia, high-speed video microscopy for evaluating ciliary beat patterns, immunofluorescent staining of the cilia in the biopsies, and genetic studies. As there had not been any epidemiological studies in Iran to detect the prevalence of PCD in the general population, the current research has been undertaken for the first time using screening tests of saccharin and measurement of the level of exhaled NO (fractional exhaled NO) to investigate the prevalence of PCD. Objectives: Primary ciliary dyskinesia (PCD) is a rare genetic disorder with the basis of an abnormal ciliary movement that causes chronic respiratory infections, bronchiectasis, infertility in males, and situs inversus. The significance of earlier diagnosis is for better care and prevention of complications. In this regard, we studied the PCD in children with bronchiectasis by saccharin test and measurement of exhaled nitric oxide. Methods: In this cross-sectional study, 31 patients with a definite diagnosis of bronchiectasis were evaluated regarding nitric oxide exhalatory measurement (FeNO) and a saccharin test for the confirmation of PCD diagnosis. The cut-off point of 20 ppb was considered as the normal level for FeNO test and the sensation of fewer than 60 minutes for the normal range of the saccharin test. Age, gender, and cardioposition were recorded for the patients. Results: Unlike the saccharine test, the measurement of exhaled nitric oxide had a high sensitivity (90.3% versus 54.8%) for the diagnosis of PCD. Cardioposition and gender did not have significant effects on the outcomes of exhaled NO and saccharin test (P-value > 0.05). Besides, the patients’ age did not affect FeNO measurement but was significantly higher among those with abnormal saccharin test (P-value = 0.028). Conclusions: The FeNO test had a remarkable sensitivity of 90.3% for the diagnosis of PCD, and its outcomes were not affected by age, gender, and cardioposition. The saccharin test had a sensitivity of 54.8% and was influenced by age, while not by gender or cardioposition. Although there are more accurate tests for diagnosis of PCD such as TEM and genetic studies, we decided to investigate PCD in children with bronchiectasis by performing two screening tests, NO and saccharin, because of several issues.