OBJECTIVECystic fibrosis (CF) is rare in Chinese mainland. We present two cases of CF patients diagnosed by gene analysis. Their clinical manifestations and genetic mutation features are analyzed in this article. It will be of special interest to pediatricians in recognition of CF.

METHODThe clinical material of two CF patients who were diagnosed by gene analysis was retrospectively analyzed.

RESULTThe first patient is a 13-year-old girl. She had a complaint of recurrent fever and cough for 6 months, expectoration for 2 months and hemoptysis for 20 days. After 3 months of her birth, she was operated on for bullae of lung. She was susceptible to upper respiratory tract infection. There was no family history of recurrent wheeze and other special diseases. Aspergillus fumigatus specific IgE was at grade 3 and aspergillus fumigatus IgG was high. Pseudomonas aeruginosa was positive in sputum culture. Sweat testing was performed and Na+ was higher. Pulmonary CT indicated bronchiectasis. Nasal sinus CT showed optical density of soft tissue within maxillary sinus and chronic bilateral sinusitis. The electron microscopy of cilia suggested immobile cilia syndrome. A heterozygotic mutation (263T > G, 2909G > A) was found after CFTR genetic mutation analysis. Both her parents were carriers. She was treated with inhalation of nebulized hypertonic saline and postural drainage for a long time. And she got better during a follow up period of 1 year. The second patient was a 10-year-old girl who complained of recurrent expectoration for 3 years and shortness of breath for half a year. She had a history of sinusitis and steatorrhea. The family history was normal. Both the lipase and insulin level in blood serum was lower.Pseudomonas aerugino and Aspergillus fumigatus were both positive in sputum culture. Aspergillus fumigatus IgE was normal. Pulmonary CT indicated bronchiolitis and bronchiectasis. Nasal sinus CT showed bilateral maxillary sinusitis. CFTR genetic mutation analysis revealed a homozygous mutation (3196C > T). Her parents and relatives did not participate in this study. Unfortunately, this child died of respiratory failure 3 months after discharge.

CONCLUSIONCFTR gene mutation was a main cause of CF. Common symptoms are those of bronchiectasis, pancreatitis and sinusitis. The two Chinese patients were diagnosed by gene analysis. One had a heterozygous mutation (263T > G, 2909G > A) and the other had a homozygous mutation (3196C > T), not ΔF508 which is common in western countries.