|Year : 2021 | Volume
| Issue : 1 | Page : 23-25
Bilateral congenital pulmonary airway malformation in an adult: Report of a rare case
Ravindran Chetambath, Jesin Kumar, Sanjeev Shivashankaran
Department of Pulmonary Medicine, DM Wayanad Institute of Medical Sciences, Wayanad, Kerala, India
|Date of Submission||28-Sep-2020|
|Date of Decision||16-Oct-2020|
|Date of Acceptance||24-Oct-2020|
|Date of Web Publication||28-Jan-2021|
Dr. Ravindran Chetambath
Navaneeth, Sarovaram Road, Calicut - 673 020, Kerala
Source of Support: None, Conflict of Interest: None
Congenital pulmonary airway malformations (CPAMs) are considered part of a spectrum of bronchopulmonary foregut malformations. Diagnosis is usually made during the antenatal or neonatal period, and is rarely diagnosed in adults. The spectrum of clinical presentations varies from asymptomatic cases to recurrent respiratory tract infections or respiratory insufficiency in adulthood. Here, we report the case of an adult female who presented with a history of recurrent respiratory tract infections since childhood. Radiological findings were in favor of bilateral CPAM. Bilateral CPAM in an adult patient is extremely rare, and it is mostly managed as bronchiectasis.
Keywords: Bronchopulmonary foregut malformation, congenital cystic adenomatoid malformation, cystic lung diseases
|How to cite this article:|
Chetambath R, Kumar J, Shivashankaran S. Bilateral congenital pulmonary airway malformation in an adult: Report of a rare case. J Adv Lung Health 2021;1:23-5
|How to cite this URL:|
Chetambath R, Kumar J, Shivashankaran S. Bilateral congenital pulmonary airway malformation in an adult: Report of a rare case. J Adv Lung Health [serial online] 2021 [cited 2021 Mar 4];1:23-5. Available from: http://www.jalh.com/text.asp?2021/1/1/23/308265
| Introduction|| |
Congenital pulmonary airway malformation (CPAM) is a rare condition characterized by immature, malformed lung tissue with cystic appearance. CPAM is seen mainly in newborns and is rarely encountered in children beyond infancy. However, few adult cases of CPAM have been reported in literature. This is mainly because the extent of disease varies considerably and? asymptomatic or minimally symptomatic cases are missed in early childhood. CPAM usually involves a single lobe, but multi-lobar and bilateral lung involvements have also been reported. Here, we present a rare case of bilateral CPAM in an adult patient.
| Case Report|| |
A 26-year-old female patient was referred with a history of fever and cough with expectoration of 6 days' duration. She was managed in a local health facility for 5 days and referred to us as the clinical response was not satisfactory. She also had exertional breathlessness. The patient was symptomatic since early childhood and was managed as a case of bronchiectasis. She used to get cough, scanty sputum, and fever, 2–3 times every year. Computed tomography (CT) thorax done in 2011 reported it as bronchiectasis. On examination, she was moderately built and nourished. She was afebrile at the time of examination and was maintaining saturation of 90% at room air with no tachypnea or tachycardia. Auscultation showed coarse crackles on both sides. X-ray chest showed few cystic lesions in both the lungs [Figure 1]. Blood examination showed leukocytosis and an elevated erythrocyte sedimentation rate. Sputum culture yielded Moraxella catarrhalis, and sputum acid-fast staining showed negativity. She was managed with broad-spectrum antibiotics. High-resolution CT (HRCT) thorax showed multiple cysts in the right upper lobe. Multiple cysts were also noted in the left lower lobe. On both sides, one large cyst was seen surrounded by a bunch of small cysts [Figure 2] and [Figure 3]. Lung parenchyma surrounding the cysts appeared normal. There was no evidence of fibrosis, mucus plugging, or volume loss. Spirometry showed restrictive pattern. Based on the clinical history and radiological pattern, a diagnosis of cystic disease of the lung involving the right upper lobe and the left lower lobe was made. The HRCT pattern of cysts was more in favor of congenital pulmonary airway malformation (CPAM) that too in two lobes. Histopathological diagnosis was needed to establish the diagnosis, but the patient and her relatives were not in favor of an invasive procedure. Hence, diagnosis in this case was based on clinical and radiological findings. Clinical features against bronchiectasis had been used in the present case to rule out the nearest differential diagnosis. Points in favour of diagnosis are absence of copious expectoration, wheeze, fibrosis, scarring and volume loss in the lung; and presence of large cysts towards the periphery near the surface of the lungs.
|Figure 1: X-ray chest posteroanterior view showing multiple cysts in the left lower zone (black arrows) and few large cysts in the right upper zone (red arrows)|
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|Figure 2: High.resolution computed tomography thorax axial cuts showing bunch of cysts in the right upper lobe. Red arrow showing the extent of cyst to the sub.pleural surface of the lung which is unusual in bronchiectasis. Few cysts are seen in the apical segment of the left lower lobe also|
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|Figure 3: High-resolution computed tomography cuts showing bunch of cysts in the left lower lobe. See the cysts reaching the surface of the lung (yellow arrowhead)|
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| Discussion|| |
CPAMs are multicystic masses of segmental lung tissue with abnormal bronchial proliferation. This entity was first described by Chin and Tang in 1949 as congenital cystic adenomatoid malformation. Later in 2002, Stocker proposed the name CPAM and classified it into the following five types:
- CPAM Type 0 – Acinar dysplasia/agenesis is a rare malformation largely incompatible with life. In this condition, lungs are small and firm with diffusely granular surface. Microscopically, it shows bronchus-like structures with muscle; glands; and numerous cartilage plates and loose, vascular mesenchymal tissue.
- CPAM Type I – It accounts for nearly 60%–65% of cases. In this case, the lesion is predominantly cystic type (measuring 3–10 cm in diameter) surrounded by smaller cysts. Microscopically, the large, thin-walled cysts are lined by ciliated pseudostratified columnar epithelium with some mucin-producing cells. Their wall is composed of fibromuscular and elastic tissue. It is operable and has a good prognosis.
- CPAM Type II – It accounts for 10%–15% of cases and mainly seen in the 1st year of life. It has a poor prognosis because it is frequently associated with other congenital anomalies. Grossly, the lesion is composed of medium-sized cysts measuring 0.5–2.0 cm in diameter that are evenly distributed and blend with the adjacent normal parenchyma. CPAM Type 2 has been noted in nearly 50% of cases of extralobar sequestration.
- CPAM Type III – It is infrequent and accounts only about 5% of cases. It is small and cystic or solid type, exclusively seen in the first few days to months of life with a characteristic male preponderance. It is commonly associated with maternal polyhydramnios or fetal anasarca. It has a high mortality rate. Cysts are small measuring <0.2 cm in diameter, forming large bulky mass involving an entire lobe or even an entire lung. Microscopically, the lesion resembles an immature lung devoid of bronchi.
- CPAM Type IV – It accounts for 10%–15% of cases and presents as hamartomatous malformation of the distal acinus. It is seen in the age range of newborn to 4 years. This lesion involves a single lobe. Grossly, large, thin-walled cysts are lined by flattened epithelium–alveolar lining cells with underlying loose, fibrovascular mesenchymal tissue.
The reported incidence of CPAM ranges from 1 in 11,000 to 1 in 35,000 live births. The accepted pathogenesis for CPAM is that an abnormal airway patterning and branching during lung morphogenesis results in the appearance of lung cysts. This condition results from the failure of normal bronchoalveolar development with a hamartomatous proliferation of terminal respiratory units in a gland-like pattern (adenomatoid) without proper alveolar formation. Histologically, they are characterized by adenomatoid proliferation of bronchiole-like structures and macro- or microcysts lined by columnar or cuboidal epithelium, presence of mucus-secreting cells, and absence of cartilage.
The microscopic features that distinguish CPAM from normal lung include the following: (i) proliferation of the terminal respiratory structures forming cysts, (ii) polypoid projections of the mucosa, (iii) increased smooth muscle and elastic tissue within cyst walls, (iv) the absence of cartilage, (v) the presence of mucous-secreting cells, and (vi) the absence of inflammation. The diagnosis is usually made either on antenatal ultrasound or in the neonatal period during the investigation of progressive respiratory distress. If large, they may cause pulmonary hypoplasia, with resultant poor prognosis. In cases where the abnormality is small, the diagnosis may not be made for many years or even until adulthood. When it does become apparent, it is usually as a result of recurrent chest infection.
CPAM in adults is very rare. Enuh et al. reported CPAM with aspergillosis in a 59-year-old male who died secondary to massive hemoptysis and development of disseminated intravascular coagulation during lobectomy. Morelli et al. described CPAM in a 38-year-old male with persistent cough and hemoptysis who did well after lobectomy. A case of CPAM in a 56-year old female was reported in 2018, which remains the second-oldest case of CPAM so far reported. Because of the higher percentage of asymptomatic cases of CPAM and various degrees of lung involvement, it might be difficult to determine the prognosis in adults. Late-onset CPAM in adults may be more complicated on radiographic images due to recurrent infections. CPAM usually involves a single lobe. The lesion involving bilateral lobes of the lung is also uncommonly encountered. In CPAM-associated literatures, a few bilateral CPAM cases in adult patients have been reported., Bilateral CPAM may appear like interstitial pneumonia because of similar CT scan presentations showing grid-like opacity through the entire lung fields. The extensive involvement of the lesion increases the risk of surgery. Therefore, most patients with such lesions are treated with conservative treatment once diagnosis is confirmed by lung biopsy.
| Conclusion|| |
CPAM in adults is very rare. Bilateral CPAM is still rare. There are only two case reports of bilateral CPAM in literature. Here, we report the case of a young female who was treated as bronchiectasis since childhood, having HRCT features suggestive of bilateral CPAM. Histopathological confirmation was not obtained considering the risk of surgery due to bilateral lung involvement. The patient and her relatives were not in favor of any invasive investigation. Hence, we have to depend on clinical and radiological findings for a diagnosis.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
| References|| |
Chin KY, Tang MY. Congenital adenomatoid malformation of one lobe of a lung with general anasarca. Arch Pathol (Chic) 1949;48:221-9.
Stocker JT. Congenital pulmonary airway malformation-a new name for and an expanded classification of congenital cystic adenomatoid malformation of the lung. Histopathology 2002;41:424-31.
Adzick NS, Harrison MR, Glick PL, Golbus MS, Anderson RL, Mahony BS, et al.
Fetal cystic adenomatoid malformation: Prenatal diagnosis and natural history. J Pediatr Surg 1985;20:483-88.
Berrocal T, Madrid C, Novo S, Arjonilla A, Gómez-León N. Congenital anomalies of the tracheobronchial tree, lung, and mediastinum: Embryology, radiology, and pathology. Radiographics 2004;24:e17.
Cass DL, Quinn TM, Yang EY, Liechty KW, Crombleholme TM, Flake AW. Increased cell proliferation and decreased apoptosis characterize congenital cystic adenomatoid malformation of the lung. J Pediatr Surg 1998;33:1043-46.
Enuh HA, Arsura EL, Cohen Z, Diaz KT, Nfonoyim JM, Cosentino PJ, et al
. A fatal case of congenital pulmonary airway malformation with aspergillosis in an adult. Int Med Case Rep J 2014;7:53-6.
Morelli L, Piscioli I, Liccill S, Donato S, Catalucci A, Del Nonno F. Pulmonary congenital cystic adenomatoid malformation, type I, presenting as a single cyst of the middle lobe in an adult: Case report. Diagn Pathol 2007;2:17.
Dheeraj R, Amitha S, Sanjeev S, Chetambath R. A case of congenital pulmonary airway malformation. The Indian Practitioner 2018;71:23-6.
Kim SR, Lee MH, Lee KA, Park SJ, Min KH, Han HJ, et al
. A 38-year-old woman with bilateral cystic lesions in both lower lung lobes. Chest 2011;140:544-8.
Plit ML, Blott JA, Lakis N, Murray J, Plit M. Clinical, radiographic and lung function features of diffuse congenital cystic adenomatoid malformation of the lung in an adult. Eur Respir J 1997;10:1680-2.
[Figure 1], [Figure 2], [Figure 3]