Isolated Unilateral Left Upper Lobe Agenesis Causing Recurrent Pneumonia

The development of the lung follows the pa ern of a tubularacinous ductal system. Disturbance of the developing pulmonary anlage in early embryonic life may give rise to some uncommon anomalies like pulmonary agenesis or in very rare occasions, atresia of a segment of respiratory tract associated with development of normal pulmonary ssue distal to the atresia1. Developmental anomalies of the lung are usually detected in the neonatal period and in early childhood. Lung agenesis, a rare congenital anomaly, is some mes associated with mul ple congenital anomalies2. We report a case of isolated unilateral le upper lobe agenesis causing recurrent pneumonia in a three month old child.


Introduction
T he development of the lung follows the pa ern of a tubular- acinous ductal system.Disturbance of the developing pulmonary anlage in early embryonic life may give rise to some uncommon anomalies like pulmonary agenesis or in very rare occasions, atresia of a segment of respiratory tract associated with development of normal pulmonary ssue distal to the atresia 1 .Developmental anomalies of the lung are usually detected in the neonatal period and in early childhood.Lung agenesis, a rare congenital anomaly, is some mes associated with mul ple congenital anomalies 2 .We report a case of isolated unilateral le upper lobe agenesis causing recurrent pneumonia in a three month old child.

The Case
A girl with low birth-weight (2000g) was born uneven ully to a healthy mother at term gesta on.Her two siblings were asymptoma c.The perinatal history was normal.No parental consanguinity was present.She had recurrent chest infec on and was admi ed and managed twice before at BPKIHS for pneumonia.This me she presented at three month of age with high grade fever, cough and diffi culty in breathing for four days.
On admission at BPKIHS, she was conscious but irritable, weighing three kilograms with length 50cm.she was not pale, afebrile without cyanosis with regular pulse rate of 132 beats per minute.She was in severe respiratory distress having stridor with diminished movements over le side of chest.Ausculta on showed no breath sound over interscapular and le supra-scapular region with coarse crackles over le infra-scapular region and right upper lobe.Cardiovascular and rest of the examina on was unremarkable.
Her inves ga ons read hemoglobin 10.5gm/dl, total leukocyte count was 21800/cmm, with normal readings of rou ne urine analysis, platelet count, and hepa c and renal func on tests.Chest radiograph showed hyperinfl a on of right lung with opacifi ed le upper and lower lung fi elds (Fig- 1).Echocardiographic examina on showed dextroposi on of the heart with no other cardiac anomaly.Ultrasound abdomen, X-rays of hands, face, spine, pelvis and lower limbs were normal.Because of the suspected le lung agenesis, chest computed tomography was performed which confi rmed le upper lobe agenesis with hyperinfl a on of le lower lobe and right lung fi eld with segmental consolida on of bilateral lower lobes (Fig- 2).She was managed conserva vely in our centre and was discharged.A er which she is on regular follow up and doing well.physiology may be feasible 4 .Pulmonary agenesis needs to be diff eren ated from pulmonary hypoplasia by the absence of bronchial tree on bronchoscopy and the absence of lung ssue on radiological inves ga ons 5 .The condi on is asymptoma c unless compromised by infec on, which can be bacterial like in our case or even mycobacterial.Diff eren al diagnosis is from atelectesis, diaphragma c hernia which can be diff eren ated with the help of tomography (HRCT), bronchography, and angiography 6 .Asymptoma c cases do not require any treatment especially when no other anomalies are present.Chest infec ons are to be treated energe cally.These cases are high-risk cases for any surgery because of low respiratory reserve and anesthe st and surgeon should take appropriate precau ons 6 .

Conclusion
In the children presen ng with recurrent chest infec on and abnormal chest radiograph, a congenital malforma on of lung may be considered in the diff eren al diagnosis.

Discussion
Pulmonary agenesis usually presents in childhood but may present in later life.If not complicated by other anomalies it is quite compa ble with normal living.The diagnosis may be suspected on chest radiography; in rare cases, however, it may be associated with cross ectopic lung, which may cause misinterpreta on of chest radiography 3 .Chest computed tomography is therefore necessary for defi ni ve diagnosis.There have been some reports of combina on of lung agenesis and complex congenital heart disease like of tricuspid atresia and severe right ventricular hypoplasia for which opera ons to establish single-ventricle circula on

Fig 1 :
Fig 1: Showing complete opacifi ca on of ie hemithorax with hyperinfl a on of right lung.

Fig 2 :
Fig 2: Showing upper lobe agenesis with hyperinfl a on of le lower lobe and right lung fi eld