CASE REPORT OF PRENATALLY DIAGNOSED CONGENITAL PULMONARY AIRWAY MALFORMATION”

Dr. Habung Yarang ,PG Resident,Department Of Obstetrics And Gynaecology, All India Institute of Medical Sciences, Raipur (CG)
Prof ( Dr.) Sarita Agrawal Proffesor and Head oF the Department Of Obstetrics And Gynaecology, All India Institute of Medical Sciences, Raipur (CG)

1.INTRODUCTION
Congenital pulmonary airway malformation (CPAM) is a benign nonhereditary congenital mass of the lung that can present as cystic or solid mass1,2.Congenital cystic lung lesions are rare; however, CPAM is the most common fetal lung lesion3 . CPAM is classified as type I, II, and III and later added type 0 and IV4,5. The average gestational age for discovery of the lung mass is 22 weeks. A commonly quoted incidence of CCAM lesions is between 1:25,000 and 1:35,000 livebirths 6.
2.CASE REPORT
A 24 years old primigravida referred to AIIMS OPD at 22week of gestation with no significant past or family history. On examination vitals were stable and per abdomen examination uterus correspond to 22 week size and fetal heart sound was heard on auscultation.
Her ultrasonography findings- congenital pulmonary airway malformation with marked mediastinal shift with hypoplastic right lungs (type 3 CPAM) and CVR 2.1.(Fig1 and Fig2.).Follow up ultrasound showed marked regression in size of CPAM and CVR 0.3 compare to previous.2D ECHO done was suggestive of mediastinal shift.
Neonatologist and paediatric surgeon opinion were taken. A term alive female baby was delivered by emergency caesarean section at 40 weeks due to fetal distress and was shifted to NICU for respiratory distress (grunt with tachypnoea) and was on CPAP.CECT thorax showed a thinned wall cystic lesion in anterior segment of left middle lobe (0.7*0.7*0.6cm) with air fluid level within it and communicating with a mildly dilated bronchiolar airway adjacent to it. Baby was reviewed in paediatric surgery department after 1 month and was advised for conservative management

Fig.1 congenital pulmonary airway malformation with marked mediastinal shift with hypoplastic right lungs (type 3 CPAM)

Fig.2 Colour Doppler showing pulmonary vessel supply to CPAM.

4.Conclusion-We have reported a case of Type III CPAM which regressed in follow up ultrasound. Multidisciplinary medical team (obstetricians, perinatologists, neonatologists and paediactric surgeon) were working in close relations and Early diagnosis and follow up of prenatally diagnosed CPAM can prevent both prenatal (hydrops)and postnatal complication with favourable outcome.The fetus with CPAM should be referred for delivery at a center with NICU

3.DISCUSSSION
CPAM is diagnosed by prenatal ultrasound demonstrating a lung tumor that may be solid or cystic, and with an absence of systemic vascular flow7 and MRI being an alternative option. In this case it was diagnosed at 22 weeks with type III CPAM lesions which account for only 10% of cases and are usually large homogeneous microcystic masses that cause mediastinal shift8. CPAM does present with a few differentials that need to be assessed, including bronchopulmonary sequestration, bronchogenic cyst, and congenital diaphragmatic hernia9. Bronchopulmonary sequestrations have a blood supply that originates from the thoracic aorta and CDH will have peristaltic movement.The overall prognosis depends primarily on the size of the lesion, as well as whether it is predominantly macro cystic or microcystic and The CCAM volume ratio (CVR). CVRs >1.6, 80% developed hydrops9. The CVR may therefore be a useful criterion to select foetuses at greatest risk for the development of hydrops. Follow up ultrasound done biweekly till if to diagnose early signs of hydrops. In this case CVR was 2.1 at presentation and was reduce to 0.3 in the follow up ultrasonography.Several reports have described disappearing fetal lung masses 8. The percentage of cases that will undergo spontaneous regression is not known, but may occur in 6% to 11% of cases8,10 seen in this case with follow up ultrasound.Fetal echocardiography should be performed in all cases of CPAM because of an increased incidence of associated cardiac anomalies, particularly truncus arteriosus and tetralogy of Fallot5.Type III CPAM can develop complication like fetal hydrops and maternal mirror syndrome which warrant urgent termination of pregnancy12.There is no need for cesarean delivery except for obstetric indication.In this case Emergency caesarean section was done for fetal distress.Open fetal surgery remains the best treatment option for type III CCAMs associated with hydrops. Some patients may not be suitable or may decline such intervention course of maternal steroids (betamethasone or dexamethasone) may be effective and Exist to resection may be Indicated .The newborn should be evaluated in the nursery to confirm the prenatal diagnosis and exclude other associated anomalies.Complete resection of the CPAM, usually by lobectomy, is the treatment of choice in CPAM10. Several authors have recommended that as long as these lesions are asymptomatic, they be observed closely and managed without resection11 as done in our case.
5.Referrences-
Bennett CT: Prenatal sonography finding of fetal lung mass at 20 weeks gestation. J Diagn Med Sonography 2003;19:101–106.
Chikkannaiah P, Kangle R, Hawal M: Congenital cystic adenomatoid malformation of lung: report of two cases with review of the literature. Lung India 2013;30:215–218.
Hagen-Ansert SL: Textbook of Diagnostic Ultrasonography, 7th ed. Amsterdam, Elsevier Mosby, 2012.
Stocker JT. Congenital pulmonary airway malformation: a new name and an expanded classification of congenital cystic adenomatoidmalformation of the lung. Histopathology. 2002;41:424-431.
Stocker JT, Madewell JER, Drake RM. Congenital cystic adenomatoid malformation of the lung: classification and morphologic spectrum. Hum Pathol. 1977;8:155-171.
Laberge JM, Flageole H, Pugash D, et al. Outcome of the prenatally diagnosed congenital cystic adenomatoid lungmalformation: aCanadian experience. Fetal Diagn Ther. 2001;16:178-186.
Walker J, Cudmore RE. Respiratory problems and cystic adenomatoid malformation of the lung. Arch Dis Child. 1990;65:649-659
Adzick NS. Fetal thoracic lesions. Semin Pediatr Surg. 1993;2:103-108. Adzick NS, Harrison MR. Management of the fetus with a cystic adenomatoid malformation. World J Surg. 1993;17:342-349.
Crombleholme TM, Leichtly KW, Howell LJ, et al. Cystic adenomatoid malformation volume ratio predicts outcome in prenatally diagnosed cystic adenomatoidmalformation of the lung.J Pediatr Surg. 2002;37:331-338.
MacSweeney F, Papagiannopoulos K, Goldstraw P, Sheppard MN, Corrin B, Nicholson AG. An assessment of the expanded classification of congenital cystic adenomatoid malformations and their relationship to malignant transformation. Am J Surg Pathol. 2003;27(8): 1139-1146
Szarnicki R, Maurseth K, deLoval M, et al. Tracheal compression by the aortic arch following right pneumonectomy. Ann Thorac Surg. 1978; 25:321-324