UNILATERAL HYPOLUCENT LUNG IN AN ADULT – PULMONARY HYPOPLASIA STILL A POSSIBILITY

Authors :  Bindu.T1, Nageshwari.AD2

 

Abstract:-

Lung hypoplasia is a rare developmental anomaly which can or cannot be associated with congenital  malformation of other organs. This condition usually diagnosed in infancy and childhood, can present in adults rarely. We herewith report a case of unilateral pulmonary hypoplasia in a young female for its rarity.

Key words: Pulmonary hypoplasia, Imaging, Radioalveolar counting, Age of presentation

Introduction: –

1-2 out of every 12,000 births have reported Unilateral pulmonary hypoplasia, a congenital anomaly of lung.(1) in pulmonary hypoplasia there is a decrease in the pulmonary lobes size with a decreased number of bronchial branching and alveoli, retaining the gross anatomical architecture of a normal lung. Anomalies associated with this pathology is mainly seen in gastrointestinal. cardiovascular(TOF/PDA), musculoskeletal,
congenital diaphragmatic hernia, urinary system, and unilateral pulmonary vasculature anomaly.(2-6) The disease may present in neonatal period, infancy, childhood or rarely even in the adult stage depending on the severity of the anomaly. In this article, we report a case of unilateral pulmonary hypoplasia in a 30 year old female.

case report;

A 30 year old female was admitted in department of respiratory medicine, in a tertiary care hospital with  complaints of lower respiratory tract infection for the past 6 months and history of occasional hemoptysis (blood streaked sputum) on & off. On general examination the patient was found to be thin built with mild pallor. In respiratory system examination the following findings were seen: mild scoliosis with drooping of left shoulder, left hemithorax appeared smaller in size with decreased chest movements, trachea was grossly shifted to the left side and apical impulse was palpable at mid axillary line left 4th intercostal space. Rib space narrowing with a dull note on percussion was seen in the left side chest. On auscultation air entry was diminished and coarse crackles audible over left chest. CBC revealed decreased hemoglobin level of 9.8g/dl with an increase in total WBC count of 18500cells/mm3. RFT/LFT/ECG were within normal limits. Sputum smear examination for AFB was negative and sputum gram stain and culture sensitivity showed streptococcal pneumoniae growth which was sensitive to quinolones and 3rd generation cephalosporins. Chest xray and CT chest with contrast confirmed the presence of hypoplastic left lung with gross volume reduction, bronchiectatic changes, mediastinal shift to the left, hypoplastic left pulmonary artery and compensatory hyperinflation of right lung.

Figure ; chest X-ray PA view showing hypolucent left lung with compenstory overinflation on the right. 3D reconstructional image on CT showing gross disparity in the size of left lung. CT Chest parenchyma window
showing hypoplasia of left lung with bronchiectatic changes. CT chest with contrast showing hypoplasia of left pulmonary arter

USG abdomen and echocardiogram which was done to rule out other associated congenital malformation was found to be normal. Bronchoscopy revealed under developed left bronchial tree with decreased size and number of bronchial branching. Right bronchial tree was normal. Patient is currently under regular follow up, treated symptomatically with antibiotics as per culture sensitivity report, mucolytics, bronchodilators and chest physiotherapy.
Discussion:
Bronchial tree development begins during 26 th-31st day of intrauterine life. Developmental disorders of lung is classified by Monaldi into 4 categories.(7)
Group 1: no bifurcation of trachea.
Group 2: only rudimentary main bronchus.
Group3: uncompleted development after bifurcation of main bronchus.
Group 4: incomplete development of small segmental/ subsegmental bronchus Boyden had classified the same into three groups(8)
1. Agenesis – complete absence of lung tissue
2. Aplasia – rudimentary bronchus with absent lung parenchyma
3. Hypoplasia– underdeveloped lung tissue and bronchus
The patient described in this article belongs to group 4 according to Monaldi and group 3 according to Boyden’s classification. Hypoplasia can be unilateral or bilateral. Bilateral hypoplasia presents during neonatal period, when severe is usually incompatible with life and associated with oligohydraminios during antenatal period. Severity of symptoms is directly proportional to the degree of hypoplasia(9). Respiratory distress immediately after birth with low APGAR score is seen in Bilateral hypoplasia. The symptoms of unilateral hypoplasia can present in childhood with recurrent respiratory infection or in some rare cases, patient may remain asymptomatic even during adulthood (10) as seen in our patient.
Radiological findings are characterized by absence of aeiration on the affected hemithorax, volume loss, crowding of ribs, elevated hemi diaphragm, shift of mediastinm to the affected side and grossly hyperinflated lung on the unaffected side. CT Chest with contrast is usually performed to assess the severity of hypoplasia and also to rule out other closely mimicking differential diagnosis like Swyer James syndrome,
bronchiectasis with atelectasis and fibrothorax. In Swyer James syndrome classical air trapping on end expiratory CT image is characteristic. Unilateral hypoplastic pulmonary artery is seen both in swyer James and pulmonary hypoplasia.
Radioalveolar counting (RAC) a newer technique is currently being used to confirm the presence of hypoplasia which compares the number of alveoli taken from a particular region with the normal control sample. Mortality rate is high (71-95%) in those presenting during neonatal period. Treatment modalities available for hypoplasia are medical/ surgical both before and after delivery. Amnioinfusion, steroids, tocolytics and antibiotics are prescribed during antenatal period and postnatal period respiratory support ranging from oxygen therapy to mechanical ventilatory support might also be needed. Treatment in an adult is usually symptomatic in the form of antibiotics, bronchodilators, mucolytics, chest physiotherapy and vaccination (influenza, Respiratory syncitial virus, pneumococcal).(11)

Conclusion:-
Unilateral pulmonary hypoplasia can present lately in adulthood and should be considered as differential diagnosis when radiological imaging shows a unilateral hypolucent lung.

References:-
1.anatomical defects. Minerva Medica, 51,3474-3478.
2. Boyden, E.A. (1955) Developmentalanomalies of the lungs. American Journal of Surgery, 89, 79-89.
3.Haddad, G.G. and Fontan, J.J.P. (2000) Development of the respiratory system. Nelson Textbook of Pediatrics, 16th Edition, 1235-1237.
4.Deniz, Ö., Tozkoparan, E., Çiftçi, F., Özkan,M., et al. (2004) Sol pulmoner aplazi (agenezi) (olgu sunumu). Gülhane Tıp Dergisi, 46,
5.Naclerio, E.A. (1959) Congenital diseases, agenesis of lung. Bronchopulmonary Diseases, 35, 309-313.
6.Roque, A.S., Burton, E.M., Boedy, R.F.,Falls, G., et al. (1997) Unilateral pulmonary agenesis without mediasti-nal displacement. Southern Medical Journal, 90, 335- 337.
7.Moore ADA, Godwin JD, Dietrich PA et al.:Swyer James Syndrome: CT findings in eight patients. Am. J. Roentgenol. 1992; 158: 1211.
8.Askenazi, S.S. and Perlman, M. (1979) Pulmonary hy-poplasia: Lung weight and radial alveolar count as crite-ria of diagnosis. Archives of Disease in Childhood, 54, 614-618.
9.Odd, D.E., Batin, M.R., Halam, L. and Knight, D.B. (2003) Primary pulmonary hypoplasia: A case report and review of the literature. Journal of Paediatrics and Child Health, 39, 467-469.
10.Chin, T. (2009) Pulmonary hypoplasia. Cited March 2009. http://www.emedicine.com/ ped/TOPIC2627.HTM
11.Natrajan G, Abdulhamid I. Pulmonary hypoplasia. Available from : 2627.htm. [cited May 2004].

How to Cite This Article:  Bindu.T, Nageshwari.AD UNILATERAL HYPOLUCENT LUNG IN AN ADULT –  PULMONARY HYPOPLASIA STILL A POSSIBILITY. Intenatioal Jornal Of Medical Case Repots Voume 3 Issue 3 Jul-Sep 2017 p 01-05

                                                                                        click here to download pdf file