Congenital pulmonary anomalies

Revision as of 17:26, 3 August 2012 by Prashanthsaddala (talk | contribs) (Symptoms)
Jump to: navigation, search
Congenital pulmonary anomalies

WikiDoc Resources for Congenital pulmonary anomalies

Articles

Most recent articles on Congenital pulmonary anomalies

Most cited articles on Congenital pulmonary anomalies

Review articles on Congenital pulmonary anomalies

Articles on Congenital pulmonary anomalies in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Congenital pulmonary anomalies

Images of Congenital pulmonary anomalies

Photos of Congenital pulmonary anomalies

Podcasts & MP3s on Congenital pulmonary anomalies

Videos on Congenital pulmonary anomalies

Evidence Based Medicine

Cochrane Collaboration on Congenital pulmonary anomalies

Bandolier on Congenital pulmonary anomalies

TRIP on Congenital pulmonary anomalies

Clinical Trials

Ongoing Trials on Congenital pulmonary anomalies at Clinical Trials.gov

Trial results on Congenital pulmonary anomalies

Clinical Trials on Congenital pulmonary anomalies at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Congenital pulmonary anomalies

NICE Guidance on Congenital pulmonary anomalies

NHS PRODIGY Guidance

FDA on Congenital pulmonary anomalies

CDC on Congenital pulmonary anomalies

Books

Books on Congenital pulmonary anomalies

News

Congenital pulmonary anomalies in the news

Be alerted to news on Congenital pulmonary anomalies

News trends on Congenital pulmonary anomalies

Commentary

Blogs on Congenital pulmonary anomalies

Definitions

Definitions of Congenital pulmonary anomalies

Patient Resources / Community

Patient resources on Congenital pulmonary anomalies

Discussion groups on Congenital pulmonary anomalies

Patient Handouts on Congenital pulmonary anomalies

Directions to Hospitals Treating Congenital pulmonary anomalies

Risk calculators and risk factors for Congenital pulmonary anomalies

Healthcare Provider Resources

Symptoms of Congenital pulmonary anomalies

Causes & Risk Factors for Congenital pulmonary anomalies

Diagnostic studies for Congenital pulmonary anomalies

Treatment of Congenital pulmonary anomalies

Continuing Medical Education (CME)

CME Programs on Congenital pulmonary anomalies

International

Congenital pulmonary anomalies en Espanol

Congenital pulmonary anomalies en Francais

Business

Congenital pulmonary anomalies in the Marketplace

Patents on Congenital pulmonary anomalies

Experimental / Informatics

List of terms related to Congenital pulmonary anomalies

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [2] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

Developmental Anatomy

Intrauterine stage

  • Four periods of development:
  • embryonic
  • pseudoglandular
  • canalicular
  • terminal sac
  • Embryonic period begins at 26 days with ventral protrusion of the foregut and ends at 32 days with appearance of 5 lobar bronchi
  • Pseudoglandular period lasts from 5th to 16th weeks and is characterized by rapid branching and formation of all conducting airways
  • Canalicular period lasts from 16th to 25th weeks and is characterized by capillary ingrowth and appearance of saccules
  • Terminal sac or alveolar period begins at 25 weeks, and alveolar development begins between the 30th and 36th weeks
  • Type I and II epithelial differentation typically occurs at 28 weeks

Neonatal stage

  • Precursors of typical acinar unit are present at birth: bronchioles, transitional ducts, and terminal saccule
  • Alveolar development continues after birth with remodeling and multiplication
  • The total adult number of alveoli are not reached until at least age 8
  • Alveolar enlargement continues until adulthood, although no new alveoli are added

Histology

  • The mature lung is characterized by closely packed alveoli divided by thin septa, occupied by capillaries
  • Capillary endothelium is typically a single cell layer with few organelles and thin cytoplasmic matrix
  • Over 95% of alveolar epithelium is type I cells, which are also very thin with few organelles
  • Type II alveolar cells are cuboidal and secrete surfactant
  • Surfactant synthesis peaks at term and decreases to adult levels shortly thereafter
  • An increase in the lecithin-sphingomyelin ratio to more than 2:1 occurs just before birth
  • Type II cells can be stimulated to produce this pattern of phospholipid by steroids, thyroxine, estrogens, beta-agonists, and increases in ventilation or tidal volume
  • Surfactant stabilizes the alveoli, lowers surface tension to keep alveoli open at low volumes, prevents alveolar wall adhesion, and helps maintain pulmonary compliance

Anatomic Variants with Normal Parenchyma

  • Superior segment of lower lobe delineated by separate fissure
  • Medial accessory left lower lobe
  • Azygous lobe - mesentery of azygous vein forms double fold of visceral pleura that isolates part of right upper lobe
  • Bilateral bilobation or trilobation
  • Situs inversus thoracis or totalis - totalis form associated with Kartagener's syndrome (situs inversus, bronchiectasis, pansinusitis - immotile cilia syndrome)

Agenesis, Aplasia, and Hypoplasia

Agenesis and Aplasia

  • Agenesis is the complete absence of carina, main bronchus, lung, and pulmonary vasculature
  • Aplasia is the development of carina and rudimentary main bronchus; absence of lung and pulmonary vessels
  • Bilateral pulmonary agenesis extremely rare and uniformly fatal
  • More than 50% of patients with unilateral agenesis have other associated anomalies
  • Agenesis does not show a right or left predominance
  • Lobar agenesis is less common that total lung agenesis

Hypoplasia

  • Failure to obtain adequate size; all components are present, but incompletely developed
  • Severity of hypoplasia determines the degree of respiratory compromise
  • Major abnormality is a decrease in the number of airway generations and pulmonary artery branchings
  • Two general causes: large diaphragmatic hernia or primary embryologic defect
  • Hernia interferes with alveolar development during last 2 months of intrauterine growth
  • Embryologic defects occur early and may be associated with other syndromes
  • Associated anomalies include oligohydramnios, prune-belly syndrome, Potter's syndrome, and scimitar syndrome
  • If associated with diaphragmatic hernia, the hypoplastic lung should not be removed at surgery, as it will recover some function with time

Congenital Lobar Emphysema

Congenital lobar emphysema is over-expansion of a pulmonary lobe with compression of other lobes and shifting of mediastinum.

Pathogenesis

  • Accounts for about 50% of all congenital lung malformations
  • Intrinsic causes: bronchomalacia due to abnormal cartilaginous support, mucus plugging, bronchial torsion, redundant mucosa, foreign body aspiration
  • Extrinsic causes: bronchial compression from pulmonary artery sling, great vessel aneurysms, enlarged cardiac chambers
  • Pulmonary hypoplasia: decreased number of alveoli become overdistended due to air trapping
  • Alveolar hyperplasia: excessive number of alveoli overexpanded a polyalveolar lobe
  • Most common in LUL, then RUL, then RML

Symptoms

  • Respiratory distress occurs in 50% of patients in the first week of life (50%)
  • 80% of infants will be symptomatic by 6 months of age
  • Most common symptoms are tachypnea, cough, cyanosis, and dyspnea
  • Pulmonary infection in the affected lobe occurs most commonly between 1 and 6 months of age
  • Presentation is uncommon after age 6 months
  • Physical findings include hyperresonance and decreased breath sounds on the affected side
  • CXR. shows hyperlucency on the affected side and mediastinal shift to the opposite side
  • Air bronchography demonstrates bronchial wall collapse with expiration if bronchomalacia is the cause

Diagnosis

The imaging findings are

  • If the plain radiograph is obtained during the neonatal period, the emphysematous lobe may be opaque and homogeneous because of fetal lung fluid or it may show a diffuse reticular pattern that represents distended lymphatic channels filled with fetal lung fluid.
  • As the fluid is absorbed, the affected segment or lobe becomes hyperlucent, progresing from alveolar opacification to interstitial reticulation to general hyperlucency.
  • Adjacent lobes and structures may be compressed by the emphysematous lobe, and sometimes ipsilateral and contralateral atelectasis may occur.

Patient #1

Patient#2

Treatment

  • Indication for surgery is life-threatening progressive insufficiency from normal lung compression
  • Careful induction of anesthesia and positive pressure ventilation
  • Immediate thoracotomy necessary in the critically ill infant, as ventilation may worsen normal lung compression by rapidly expanding the affected lung
  • Surrounding atelectatic normal lung tissue should be preserved
  • Lobectomy should result in cure
  • Long-term outlook is good with relatively normal PFT's

Pulmonary Cysts

Pulmonary Cysts are cystic structures within the pulmonary parenchyma. The composition of the cyst wall is determined by its origin: bronchial glands, cartilage, or alveolar epithelium.

Pathology

  • Congenital cysts are typically unilocular and confined to a single lobe; the lower lobes are more commonly involved
  • Congenital cysts that persist for more than 1 year are unlikely to resolve spontaneously
  • Multiple cysts are rarely congenital and are probably acquired; causes include staphylococcal pneumonia and cystic fibrosis.
  • Multiple cysts may fluctuate in size and can develop rapidly
  • CXR usually adequate for identification

Symptoms

  • Expansion results in respiratory distress
  • Infection causes fever, cough, and sepsis

Treatment

  • Solitary congenital cysts can be treated with cystectomy or lobectomy if necessary
  • Infected solitary cysts should be treated with antibiotics and resected when quiescent
  • Multiple cysts should be treated as part of underlying systemic disease; surgical intervention is rarely required and is contraindicated for pneumatoceles
  • Chest tube placement or aspiration for diagnosis is discouraged for tension cysts, as this can result in empyema

Cystic Adenomatoid Malformation

Cystic adenomatoid malformation is thoracic hamartoma with overgrowth in varying amounts of bronchioles and alveoli, so it characteristically can range from cystic to nearly solid masses within the lung. Cartilage, however, is not present in this lesion.

Pathology

  • Typically confined to a single lobe
  • Progressive air trapping in cystic areas leads to over distension of involved lobe
  • Three subtypes (see table below)
  • High incidence of associated congenital anomalies and death with type II


Subtypes of Cystic Adenomatoid Malformation

Symptoms

  • Progressive respiratory distress in a newborn infant
  • Tachypnea, subcostal retraction, cyanosis
  • Older child - chronic pulmonary infection
  • Differential should include congenital diaphragmatic hernia, and barium swallow will differentiate the two

Treatment

  • Identification of the lesion is the indication for surgery, with or without symptoms
  • Lobectomy is usually adequate
  • Attempt at segmentectomy is usually met with prolonged air leak and complications

Bronchogenic Cysts

Bronchogenic cysts are congenital cystic lesions arising from abnormal budding of primitive tracheobronchial tree; composed of fibrous tissue interposed with normal bronchial elements

Pathology

  • Cysts can occur either in the parenchyma (70%) or the mediastinum (30%)
  • The most common locations are paratracheal, carinal, hilar, and paraesophageal
  • Generally round and unilocular
  • Lined with ciliated columnar epithelium
  • Most do not communicate with the tracheobronchial tree
  • Can mimic lobar emphysema from bronchial obstruction
  • Can become secondarily infected

Symptoms

  • Most common presentation in the neonate is progressive dyspnea, wheezing, stridor, and cyanosis
  • Obstructive symptoms occur most commonly in infants less than 1 year of age
  • Paratracheal, carinal, and hilar cysts are commonly asymptomatic
  • Communicating cysts are almost always symptomatic: productive cough, fever, hemoptysis
  • CXR shows homogenous, sharply delineated cyst; air/fluid levels may be present in communicating cyst
  • CT is the test of choice for diagnosis and anatomic delineation

Treatment

  • Indications for surgery include increasing cyst size, air/fluid level, symptomatic cyst, and subcarinal cyst
  • Small, asymptomatic cysts can be followed with interval CXR
  • Cyst excision with sparing of surrounding pulmonary tissue is the treatment of choice

Intralobar Pulmonary Sequestration

Intralobar pulmonary sequestration is a segment of lung parenchyma that is within the normal pleural confines, but does not communicate with the tracheobronchial tree and is supplied by the systemic circulation.

Pathology

  • Unicystic or polycystic parenchyma with extensive fibrosis and vascular sclerosis
  • Arterial supply is usually from the thoracic aorta (75%) or abdominal aorta (20%)
  • Venous drainage is usually to the pulmonary veins
  • Right-sided lesions more often have other venous drainage
  • Much more frequent than extralobar type

Symptoms

  • Recurrent episodes of infection in older children and adolescents
  • CXR shows cystic structure with or without air-fluid level
  • CT is procedure of choice; aortography and barium swallow may be necessary for anatomy

Treatment

  • Identification of the lesion is indication for surgery
  • Careful ligation of the anomalous artery followed by resection
  • Prevents long-term infection and possible neoplastic changes

Extraobar Pulmonary Sequestration

Extraobar pulmonary sequestration is a segment of lung parenchyma with distinct and separate pleural investment; does not communicate with the tracheobronchial tree and is supplied by the systemic circulation.

Pathology

  • Mass of loose, spongy parenchyma with multiple small cysts and dilated bronchioles and ducts
  • Arterial supply is also usually from the thoracic or abdominal aorta
  • Venous drainage is usually to the azygous or hemiazygous system
  • More common on the left side and usually found between the lower lobe and the diaphragm

Symptoms

  • Most present in neonatal period due to respiratory distress
  • CXR shows triangular homogenous mass with apex pointing toward hilum
  • CT may provide additional localization, but vessels often too small to identify

Treatment

  • Identification of the lesion is indication for surgery
  • Careful ligation of the anomalous artery followed by resection
  • As with intralobar sequestration, resection prevents long-term infection and possible neoplastic changes
Comparison of ILS and ELS (Adapted from Sabiston and Spencer)

Source

  • CTSNet Wiki Notes

References

  • Olutoye OO, Coleman BG, Hubbard AM, Adzick NS. Prenatal diagnosis and management of congenital lobar emphysema. J Pediatr Surg. 2000 May;35(5):792-5.
  • Evrard V, Ceulemans J, Coosemans W, De Baere T, De Leyn P, Deneffe G, Devlieger H, De Boeck C, Van Raemdonck D, Lerut T. Congenital parenchymatous malformations of the lung. World J Surg. 1999 Nov;23(11):1123-32.
  • Cloutier MM, Schaeffer DA, Hight D. Congenital cystic adenomatoid malformation. Chest 1993 103(3):761-4.
  • Martinod E, Pons F, Azorin J, Mouroux J, Dahan M, Faillon JM, Dujon A, Lajos PS, Riquet M, Jancovici R. Thoracoscopic excision of mediastinal bronchogenic cysts: results in 20 cases. Ann Thorac Surg. 2000 May;69(5):1525-8.
  • Ribet ME, Copin MC, Gosselin BH. Bronchogenic cysts of the lung. Ann Thorac Surg. 1996 Jun;61(6):1636-40.
  • Suen HC, Mathisen DJ, Grillo HC, LeBlanc J, McLoud TC, Moncure AC, Hilgenberg AD. Surgical management and radiological characteristics of bronchogenic cysts. Ann Thorac Surg 1993 55(2):476-81.
  • Cioffi U, Bonavina L, De Simone M, Santambrogio L, Pavoni G, Testori A, Peracchia A. Presentation and surgical management of bronchogenic and esophageal duplication cysts in adults. Chest. 1998 Jun;113(6):1492-6.
  • Gustafson RA, Murray GF, Warden HE, Hill RC, Rozar GE. Intralobar sequestration. A missed diagnosis. Ann Thorac Surg 1989 47(6):841-7.
  • Bratu I, Flageole H, Chen MF, Di Lorenzo M, Yazbeck S, Laberge JM. The multiple facets of pulmonary sequestration. J Pediatr Surg. 2001 May;36(5):784-90.
  • Bailey PV, Tracy T Jr, Connors RH, deMello D, Lewis JE, Weber TR. Congenital bronchopulmonary malformations. Diagnostic and therapeutic considerations. J Thorac Cardiovasc Surg 1990 99(4):597-602.
  • Winters WD, Effmann EL. Congenital masses of the lung: prenatal and postnatal imaging evaluation. J Thorac Imaging. 2001 Oct;16(4):196-206.

See Also

External Links

Cost Effectiveness of Congenital pulmonary anomalies

| group5 = Clinical Trials Involving Congenital pulmonary anomalies | list5 = Ongoing Trials on Congenital pulmonary anomalies at Clinical Trials.govTrial results on Congenital pulmonary anomaliesClinical Trials on Congenital pulmonary anomalies at Google


| group6 = Guidelines / Policies / Government Resources (FDA/CDC) Regarding Congenital pulmonary anomalies | list6 = US National Guidelines Clearinghouse on Congenital pulmonary anomaliesNICE Guidance on Congenital pulmonary anomaliesNHS PRODIGY GuidanceFDA on Congenital pulmonary anomaliesCDC on Congenital pulmonary anomalies


| group7 = Textbook Information on Congenital pulmonary anomalies | list7 = Books and Textbook Information on Congenital pulmonary anomalies


| group8 = Pharmacology Resources on Congenital pulmonary anomalies | list8 = AND (Dose)}} Dosing of Congenital pulmonary anomaliesAND (drug interactions)}} Drug interactions with Congenital pulmonary anomaliesAND (side effects)}} Side effects of Congenital pulmonary anomaliesAND (Allergy)}} Allergic reactions to Congenital pulmonary anomaliesAND (overdose)}} Overdose information on Congenital pulmonary anomaliesAND (carcinogenicity)}} Carcinogenicity information on Congenital pulmonary anomaliesAND (pregnancy)}} Congenital pulmonary anomalies in pregnancyAND (pharmacokinetics)}} Pharmacokinetics of Congenital pulmonary anomalies


| group9 = Genetics, Pharmacogenomics, and Proteinomics of Congenital pulmonary anomalies | list9 = AND (pharmacogenomics)}} Genetics of Congenital pulmonary anomaliesAND (pharmacogenomics)}} Pharmacogenomics of Congenital pulmonary anomaliesAND (proteomics)}} Proteomics of Congenital pulmonary anomalies


| group10 = Newstories on Congenital pulmonary anomalies | list10 = Congenital pulmonary anomalies in the newsBe alerted to news on Congenital pulmonary anomaliesNews trends on Congenital pulmonary anomalies


| group11 = Commentary on Congenital pulmonary anomalies | list11 = Blogs on Congenital pulmonary anomalies

| group12 = Patient Resources on Congenital pulmonary anomalies | list12 = Patient resources on Congenital pulmonary anomaliesDiscussion groups on Congenital pulmonary anomaliesPatient Handouts on Congenital pulmonary anomaliesDirections to Hospitals Treating Congenital pulmonary anomaliesRisk calculators and risk factors for Congenital pulmonary anomalies


| group13 = Healthcare Provider Resources on Congenital pulmonary anomalies | list13 = Symptoms of Congenital pulmonary anomaliesCauses & Risk Factors for Congenital pulmonary anomaliesDiagnostic studies for Congenital pulmonary anomaliesTreatment of Congenital pulmonary anomalies

| group14 = Continuing Medical Education (CME) Programs on Congenital pulmonary anomalies | list14 = CME Programs on Congenital pulmonary anomalies

| group15 = International Resources on Congenital pulmonary anomalies | list15 = Congenital pulmonary anomalies en EspanolCongenital pulmonary anomalies en Francais

| group16 = Business Resources on Congenital pulmonary anomalies | list16 = Congenital pulmonary anomalies in the MarketplacePatents on Congenital pulmonary anomalies

| group17 = Informatics Resources on Congenital pulmonary anomalies | list17 = List of terms related to Congenital pulmonary anomalies


}}



Linked-in.jpg