Clinical and paraclinical charateristics of pulmonary agenesis and hypoplasia in children treated at national pediatric hospital – Nguyen Thi Mai Hoan

Journal of military pharmaco-medicine n o 4-2018 180 CLINICAL AND PARACLINICAL CHARATERISTICS OF PULMONARY AGENESIS AND HYPOPLASIA IN CHILDREN TREATED AT NATIONAL PEDIATRIC HOSPITAL Nguyen Thi Mai Hoan*; Dao Minh Tuan*; Mai Xuan Khan** SUMMARY Objectives: To provide better understanding of pulmonary agenesis and hypoplasia. Subjects and methods: A retrospective and prospective descriptive study on all patients with pulmonary agenesis and hypoplasia admitted to Respiratory Department, National Pediatric Hospital from January 2011 to December 2016. Results and conclusion: In the 6-year-period study, there were a total of 21 patients with pulmonary agenesis and hypoplasia (0.079%) admitted to Respiratory Department. 14 of them had pulmonary agenesis and 6 had pulmonary hypoplasia. 80% of patients were younger than 6 months old, the earliest diagnosis was during the fetal period whereas the latest was a 12-year-old patient and high female-to-male ratio. The most common signs and symptoms were coughing, wheezing, dyspnea, decreased vesicular breath sound and recurrent pneumonia. Radiologic imaging: Hemithorax white-out, unilateral pulmonary artery agenesis or pulmonary artery atresia. * Keywords: Pulmonary agenesis; Pulmonary hypoplasia; Children. INTRODUCTION Pulmonary agenesis and hypoplasia are characterised by the incomplete development of airways and lung parenchyma. The severity of this disorder depends on the stages of lung development during the fetal period and the presence of other associated anatomical abnormalites. Pulmonary agenesis and hypoplasia occured in the embryonic stage (about 4 weeks of gestational age) when the 'primitive' lung is formed. The reason is unknown but genetic factors, environment and chemicals might be the causes [6]. The most typical characteristics consist of the incomplete development of the lung parenchyma, which still has bronchial stump or carina as in aplasia and is usually diagnosed at 23 to 30 weeks of gestational age. The severity of the disease depends on associated congenital anomalies (50% with cardiovascular anomalies), patients with right-sided agenesis/hypoplasia have longer life expectancy than those with left sided [1]. Abdominal aortic hemorrhage at 4 months of pregnancy is related to pulmonary agenesis/hypoplasia. * National Pediatic Hospital ** 103 Military Hospital Corresponding author: Nguyen Thi Mai Hoan (maihoannhp@yahoo.com.vn) Date received: 09/01/2018 Date accepted: 26/03/2018 Journal of military pharmaco-medicine n o 4-2018 181 Since it is such a rare condition with the rate of 1/10,000 - 15,000 live births [1], we conducted this research to give better understanding of pulmonary agenesis and hypoplasia. Objectives: To assess the rate of pulmonary agenesis and hypoplasia and to present clinical manifestations, radiologic imaging and laboratory findings of these diseases. SUBJECTS AND METHOD 1. Subjects. All patients with pulmonary agenesis and hypoplasia admitted to Respiratory Department, National Pediatric Hospital from January 2011 to December 2016. 2. Method. - Research design: A retrospective and prospective descriptive study. - Technique: Review the medical records of patients with the definitive diagnosis of pulmonary agenesis/hypoplasia at discharge and also study the admitted patients, those with definitive of pulmonary agenesis/hypoplasia during treatment. - Sampling criteria: Patients with pulmonary agenesis/hypoplasia. - Diagnostic criteria: + Clinical manifestations: Wheezing, postnatal respiratory failure, prolonged cough, recurrent pneumonia. + Radiologic imaging: Chest radiograph, thoracic CT-scan and echocardiography. RESULTS AND DISCUSSION 1. Age, gender and obstetric history of subjects. In this research, there were 21 cases in total, with 15 cases of pulmonary agenesis and 6 cases of pulmonary hypoplasia, accounting for 0.79% children admitted to Respiratory Dept. According to Conway K et al, pulmonary agenesis rate is 1/100,000. Figure 1: Sex distribution. In terms of sex, female/male ratio 15/7 = 2 (this means that females outnumbered males but as reported by previous researches, there was no gender difference [2]). Table 1: Characteristics of sex in both pulmonary agenesis/hypoplasia. Pulmonary agenesis Pulmonary hypoplasia Sex n % n % Total Male 5 23.81 2 9.52 33.33 Female 10 47.62 4 19.05 66.67 Total 15 71.43 6 28.57 100 In terms of age, 80% of subjects were younger than 6 months old, the earliest diagnosis was at fetal period (6 months), the latest was 12 years old; similar to the previous research [1]. Take history into consideration, amongst the patients with pulmonary agenesis and hypoplasia, there were no Journal of military pharmaco-medicine n o 4-2018 182 notorious obstetric history: 9 preterm cases accounted for 42.85%, 3 cases with congenital abnormalites (2 with congenital heart disease, 1 with congenital gastrointestinal anomaly), 3 cases with oligohydramnios, 1 case whose mother had flu during her first trimester [5]. 2. Rates of pulmonary agenesis and hypoplasia. Table 2: Pulmonary agenesis Pulmonary hypoplasia Position n % n % Total Right 10 47.62 3 14.28 61.9 Left 5 23.81 3 14.29 38.1 Total 15 71.43 6 28.57 100 There were 15 cases of pulmonary agenesis (71.43%) and 6 cases of pulmonary hypoplasia (28.57%) with the prevalence of the right-side, consistent with the previous research. Figure 2: The ratio of right-sided to left-sided. Pulmonary agenesis/hypoplasia was seen in 65% of the patients, in agreement with previous research. 3. Clinical and paraclinical findings of pulmonary agenesis and hypoplasia. Table 3: Pulmonary agenesis Pulmonary hypoplasia Total Symptoms n % n % n % Cough 15 71.43 6 28.57 20 100 Fever 3 14.29 1 4.76 5 19.05 Wheezing 9 42.86 6 28.57 15 71.43 Stridor 5 23.81 1 4.76 8 28.57 Journal of military pharmaco-medicine n o 4-2018 183 Dyspnea 15 71.43 6 28.57 20 100 Retractions 10 47.62 6 28.57 16 76.19 Cyanosis 5 23.81 2 9.52 7 33.33 Decresead esicular sound 14 66.67 6 28.57 20 95.24 Wheezes 6 28.57 2 9.52 8 38.09 Rhonchi 7 33.33 4 19.05 11 52.38 Crackles 12 57.14 6 28.57 18 85.71 * Clinical manifestations: Symptoms: cough (100%), wheezing (71.43%), stridor (28.57%), dyspnea (100%) retractions (76.19%), cyanosis (33.33%) often seen in children younger than 3 months old, mainly in those younger than 6 months old, rhonchi (52.38%), crackles (85.71%). The most frequent reason for admission in children younger than 6 months of age was respiratory failure, contradictory to airway malformation which are wheezing and stridor. Table 4: Laboratory findings and radiologic imaging. Pulmonary agenesis Pulmonary hypoplasia Total Symptom n % n % n % Inflammatory response 7 33.33 3 14.29 10 47.62 Anemia 7 33.33 5 23.81 12 57.14 Hemithorax white-out 15 71.43 6 28.57 20 100 Pulmonary agenesis/atresia 15 71.43 6 28.57 20 100 Inflammatory response: WBC > 10 G/l and CRP > 10 mg/L More than 80% of subjects were admitted to the hospital with symptoms of cough, dyspnea and crackles. DISCUSSION Pulmonary agenesis and hypoplasia are congenital disease defined as incomplete development of airways and parenchyma. The ratio is 9 to 11 per 100,000 [5]. According to previous researches [2, 5], male-female ratio is balance but in this research it shows a prevalence in female more than in male. 80% of subjects were early diagnosed before 6 months of age, the same as other researches [3, 6]. There were 3 cases with associated congenital anomalies, accounting for 14.29%, different from other researches [2, 4] which was up to 50%. - Clinical finding is early respiratory failure and can cause neonatal death, others might have recurrent respiratory infections [1]. Journal of military pharmaco-medicine n o 4-2018 184 - Radiologic imaging: hemithorax white-out, pulmonary artery agenesis or atresia. Echocardiography and angiography support the diagnosis of pulmonary agenesis and hypoplasia [3]. CONCLUSION Pulmonary agenesis/hypoplasia is a rare condition with the incomplete development of lung parenchyma during the fetal period, usually associated with congenital heart and gastrointestinal defects. We reported only 21 cases during 6 year period study, accounting for 0.79% patients admitted to Respiratory Department in National Pediatric Hospital. The disease is more prevalent in female, double the number as found. The disease usually manifests early and can cause neonatal death. The most common signs and symptoms are coughing, wheezing, dyspnea and retractions. However, sometimes the disease is accidentally discovered due to respiratory infection, decreased vesicular sound. The radiologic imaging of the disease in X-ray and CT-scan are hemithorax white-out, pulmonary agenesis or atresia. REFERENCES 1. Berger R.M, Beghetti M, Humpl T, Raskob G.E, Ivy D.D, Jing Z.C et al. Clinical features of paediatric pulmonary hypertension: A registry study. Lancet. 2012, Feb 11, 379 (9815), pp.537-546. 2. Conway K, Gibson R.L et al. Pulmonary agenesis: Expansion of the VCFS phenotype. Am J Med Genet. 2002, 113, pp.89-92. 3. Hofmann A.D, Friedmacher F, Takahashi T, Gosemann J.H, Puri P. 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