Congenital Lung Disease Flashcards
Clinical Approach to Congenital Lung Lesions
1) Describe what is actually seen on antenatal/postnatal imaging - do not make a diagnosis as this requires pathology.
2) Description should be in common language, avoid latin and ambiguous language.
3) Need to ensure lung AND other organs looked at in systematic manner - abnormalities are often multiple.
4) Keep clinical and pathological descriptions separate. Pathologist makes diagnosis after excision.
Antenatal presentation of congenital lung disease
Intrathoracic mass
Pleural effusion
Fetal hydrops
Oligo or polyhydramnios
Newborn presentation of congenital lung disease
Respiratory Distress Stridor Bubble secretions in mouth, not able to swallow Failure to pass NG tube Unable to establish an airway Cardiac failure Poor respiratory effort Cyanosis in a well baby
Later childhood/adulthood presentation of congenital lung disease
Recurrent infection (including TB and Aspergillus) Hemoptysis. hemothorax Bronchiectasis, bronchopleural fistula Steroid resistant airway obstruction Cardiac failure Malignant transformation Cyanosis Coughing on drinking Chance finding Air embolism
Differential diagnosis of Solid Fetal intrathoracic lesions
Microcystic adenomatoid malformation Pulmonary sequestration Right sided diaphragmatic hernia tracheal/laryngeal atresia Rhabdomyoma Mediastinal teratoma
Differential diagnosis of Cystic Fetal Intrathoracic lesions
Macrocystic adenomatoid malformation CDH Bronchogenic cyst Mediastinal encephalocele Pleural and pericardial effusion
Characteristics of CDH
Assoc abn: aneuploidy (Trisomy 13,18), genetic synd (ex: Fryns syndrome), structural (ex: cleft lip and palate, midline anomalies, cardiac, NT defect like myelomeningocele)
Lung hypoplasia due to inhibited development by gut herniation
L>R.
- Left → mediastinal shift, abdo viscera in thorax, cystic structure (stomach) in thorax
- Right → liver herniated (however same echogen as fluid-filled lung), only clue often= mediastinal shift (and needs to be there at time of the scan)
Best prognostic indicator: Lung-to-Head ratio (LHR)
Good prog factors: Isolated Left, Intra-abdominal stomach, Dx after 24-weeks
Presentation of Upper Respiratory Tract Atresia
Suspected when you seen enlarged, uniformly hyperechogenic lungs on U/S prentally
- Other feat: mediastinal compression, flat/convex diaphragm, hydrops, polyhydramnios
Differential includes subglottic stenosis and bilateral microcystic CPAM
When to consider airway abnormality?
abnormal cry, weak/husky voice, recurrent croup-like eps - Feeding difficulty may also be a feature: recurrent aspiration (laryngeal cleft) or respiratrory distress + GERD (larnygomalacia)
Characteristics of Laryngeal webs/atresia
Laryngeal lumen recannalizes by 10th week - failure = laryngeal web or atresia.
Laryngeal atresia : Part of CHAOS - congenital high airway obstruction syndrome
Characterized by large echogenic lungs, dilated distal airway, inverted diaphragm, ascites.
Laryngeal Webs: strong assoc w/ 22q11.2 del
- Majority = anterior - present w/ aphonia, abn cry or obstruction
- May be thin band btw Vocal cords OR assoc. w/ abn cricoid ring w/ assoc subglottic stenosis
Characteristics of Laryngeal clefts
Laryngeal cleft = failure of tracheo-esophageal septum
Note: Clefts can occur in assoc w/ TEF, represent a commonly missed cause of aspiration
Classification and Mgmt:
- Type I = Inter-arytenoid. Mgmt: 1st line = conservative (thickening). If fails endoscopic repair.
- Type 2 = Up to partial Cricoid cleft. Mgmt: if small = endoscopic. Large = open repair.
- Type 3 = Complete cricoid - to cervical trachea Mgmt = open repair: suturing vs. fascial graft
- Type 4 = Extension into thoracic trachea = ↑↑ mobird/mortality. Thoracotomy +/- ECMO vs. palltv
Characteristics of Laryngomalacia
Most common UA abnormality
Spectrum of anomalies, dynamic:
Short AE folds → omega epiglottis, prolapsing arytenoid
cartilages, (ary)epliglottic redundancy w/ prolapse
Symp: Inspiratory stridor, noisy breathing which starts at ~1wk
Assoc: Feeding difficulty w/ incr WOB, regurg, aspiratn (4-40%), short feeds. ↓ wt gain if severe
Natural Hx: Resolution in 2nd year of life
Mgmt: Diagnosis - confirm w/ flex endoscopy, reassurance, follow-up (wts)
Active mgmt - for severe (<10%) = supraglottosplasty.
Characteristics of Unilateral VC paralysis
Unilateral = usually peripheral
- L > R recurrent laryngeal since L longer
- Unilateral may be assoc. w/ cardiac abn, birth traum
- Diagnosis of unilateral often delayed: No obstruction, +weak/hoarse voice
Work-up: Image whole recurrent laryngeal N - assess abn of skull base, neck, thorax
If compensation inadequate, Rx: contra-lateral bulking or cord medialization
Characteristics of Bilateral VC paralysis
Stridor, often biphasic, inspiratory > expiratory
Traditional mgmt: Tracheostomy, may be avoided in ~50% - If possible, treat underlying neuro abn
Alternative Rxs: to ↓uaw resistance - unilat excision of part of cord/arytenoid
Cord lateralization (open) also possible, may allow decannulization
If no recovery by 2-yrs, presume PERMANENT - consider cord surgery to reverse trache
Minor risk of aspriation post cord resection
Difference between Laryngocele and Saccular cyst
Laryngocele = air-filled, may cause obstruction
Saccular cyst = mucous filled, in false cords/aryepiglottic folds, may obstruct
Characteristics of Subglottic/Tracheal Hemangioma
Benign vascular tumors (L>R), grow for 1st 12-18mo → slow involution to resolution
Asymptomatic at birth → a/w obstruction by ~3mo
Diagnosis: Endoscopic - small, compressible blueish mass in subglottic area (no biopsy reqd)
Treat: 1st line: Propranolol → rapid regressn. 2-3 mg/kg/d BID-QID x~12m. Monitor HR, BP, Glc
Other: systemic/lesional steroid, laser, open excision
Which is more common - congenital or acquired subglottic stenosis?
Acquired > Congenital. 1° RF = Intubation
Difference between Primary and Secondary Tracheomalacia
Primary = intrinsic abnormality in tracheal wall (Primary congenital may be assoc. w/ bronchomalacia. Also found w/ TEF, laryngeal cleft)
Secondary = extrinsic compression (usu cardiovascular abn)
- Double Ao Arch = concerntric comp.
- Anomalous innominate artery = compress R anterior
- Pulmonary artery sling = compress R mainstem
Management: Most cases - no active rx, reach parents CPR +/- chest physio
Most common association with Congenital Tracheal Stenosis
Pulmonary Artery Sling
Congenital Bronchial Stenosis vs Atresia
Stenosis: most often mainstem or RML bronchus
- May produce acute or chronic pulmonary infection,
- Ideal environment for suppuration, atelectasis, bronchiectasis
Atresia: usually asymptomatic, incidental finding or radiography
- often results in cystic degeneration of distal lobe;
- Distal airspace may be mucus-filled / cystic, often in continutity w/ area of hyperinflation -Difficult to distinguish from CPAM/CTM w/o histology, or CLHL/CLE due to mucus-plug
With disorders of bronchial laterality, how do you figure out which is the right lung?
3 lobes, short mainstream
*-Important to disting laterality defect (PCD concern) vs hypoplastic R-lung causing dextroposition
Characteristics of Mounier-Kuhn syndrome
congenital tracheobronchomegaly → tracheomalacia, bronchiectasis, dilated airway
Characteristics of Williams-Campbell syndrome
diffuse bronchomalacia affecting generations 2-7.
Causes of Bilateral Congenital Small Lungs
1) Lack of space = Abnormal thoracic, abdominal or amniotic cavity contents
2) Abnormal vascular supply = Pulmonary valve or artery stenosis, ToF
3) Neuromuscular disease = CNS, anterior horn cell, peripheral nerve or muscle disease reducing fetal breathing movements
Causes of Congenital Small Lungs due to Extrapulmonary Mechanical Factors
1) Abnormal thoracic contents = Diaphragmatic hernia, pleural effusion, large congenital thoracic malformation
2) Thoracic compression from below = Abdominal tutors, Ascites
3) Thoracic compression from the sides = Amniotic banks, Oligohydramnios, Asphyxiating dystrophy/scoliosis or other chest wall deformity
Characteristics of congenital small lungs
-Alveoli ↓ in size and/or #
-Bronchi may be underdeveloped also -Hyploplasia IF lung : body wt ratio < 0.012 -Many assoc malfomations
-Early correction of abnormality may allow alveolar growth
Note Aw branching complete @ 16wk
Characteristics of Bronchogenic cysts
- Most common cyst of infancy
- ~50% in mediastinum close to carina
- Other locations: along esophagus, tracheobronchial tree, rarely parenchyma
- Usu singluar, unilocular, R > L. Contain systemic blood supply.
- Symptoms 2° to compression of airways or complications (IE hemorrhage, infection)
Characteristics of Enterogenous cysts
- Esophageal (w/n wall of esophagus),
- Gastroenteric (duplication) - unconnected to esophagus, often close to vertebrae (6-8). - Cause of POSTERIOR mediastinal mass
Symptoms - due to pressure, infection, hemorrhage, or due to vertebral anom
-Gastric mucosa → ulceration. Malignangt transfomatn ++rare.
5 types of CPAM
Type 0: “acinar dysplasia” - rare, incompatible w/ life. Lungs = small, firm. Histology shows bronchial-airway and abundant mesenchymal tissue.
Type 1: Most common, best prognosis. Usu localized to 1-part of 1-lobe. Multiloculated cysts, larger than 2-cm by defn. Assoc w/ mucous cell hyperplasia (35-50%) - if this extends beyond the cyst: “ bronchioloalveolar carcinoma” - a mucinous adenoca good prognosis post- resection
Type 2: Second most freq. Cause resp distress in 1st month, assoc w/ renal agenesis, CV defects, CDH, syringomelia. Macroscopically = spongelike w/ multiple small cysts.
Type 3: Uncommon, almost all ♂, involves + expands a whole lobe w/ compressn of other lobes +/- hypoplasia. Macroscopic: soild. Absent pulm. arteries. ~Same as pulmonary hyperplasia.
Type 4: V. rare, peripheral thin walled cysts,(alveolar type 1, 2 cells), often
multiloculated. Continuum w/ type I pleuropulmonary blastoma (PPB). ∴If stroma hypercellular -
treat as PPB.
Characteristics of Pulmonary Sequestration
Pulmonary tissue, isolated from fxning lung w/ systemic arterial supply.
Two variants: Intrapulmonary > Extralobar sequestration
Pathological classification: “complex bronchopulmonary-foregut malformation”
Intralobar - usu posterior basal LLL. More than 50% diagnosed as adult - often asymptomatic.
- Usually drain into pulmonary system (=shunt)
Extralobar - usu beneath LLL, 15% abdominal. More often detected in neonates - assoc abn
- Usu. drain into azygous
Both types: pulmonary tissue cystic w/ disorganized, airless alveoli, bronchi, cartilage, etc.
May becomes inftected, atelectattic, bronchiectatic. Histologically similar to Type-2 CPAM.
Treatment: Surgical excision. Vascular supply delineated prior. Collateral embolizatn considered
Characteristics of Congenital Large Hyperlucent Lobe
Presentation 50% neonatal, other early infancy
Etiology - partial obstruction - (IE mucosal flaps, deficient bronchial cartillage).
-Histologically: Majority = Normal alveolar count but w/o maturation
Affected area: LUL (42%), RML (35%), RUL (21%), LLs (2%)
Lobe overdistends (may heniate), displaces adjacent lobes + mediatinal structures
Diagnosis: Following presentation of resp distress, or incidentally on CXR later in life Presentation in Infancy:
Findings similar to tension PTX: hyperresonance, decr breath sounds, deviatn of mediastinum -CXR: hyperlucent lobe w/ compressionn of adjacent/contralat lobes/structures, depressedd diaphragm
NB Difficult to differentiate distended lobe from contra-lateral hypoplasia
- Bronchoscopy may reveal cause of intrinsic obstruction (IE FB, inspissated mucous)
- CT may be useful to R/O contra-lateral hypoplasia
2 groups of Congenital Large Hyperlucent Lobe
Intrinsic bronchial obstruction: inspissated material/mucous, granuloma (intubatn), bronchial stenosis/atresia (Pores of Kohn)
Extrinsic comp: congenital heart disease / abn great vessels (more gradual), bronchogenic cysts.
Also: Contra-lateral small lung: absent lung, hypoplastic lung, contra-lateral lobar/lung collapse
Characteristics of TEF
Etiology - Isolated EA = deletions in gutrathione S-transferase gene
- Syndromic: CHARGE (CHD7 mut), VACTERL (FOXF1 or ZIC3 poly-ala exp)
Pathology - incomplete mesodermal separation of the primitive foregut → fistula
- TEF commonly assoc w/ EA. 85% of EA assoc. With fistula.
- Upper pouch usu large, blind sac - distal portion typically at level of lower trachea -Lower esophageal segment small - originates from distal membranous trachea, carina or right mainstem
Most common type of TEF
-EA with Distal-TEF most common
Associations with TEF
- 2⁄3 have assoc abn -20% have BW <5th %ile
- Assoc. w/ Charge, Vacterl.
- 6% of Trisomy 13,18,21.
- Other: Potter’s, PRS, polysplenia, DiGeorge,
- Cardiac anomalies: 30-50%
- 47% tracheobronchial anom: tracheomalacia, lung agenesis/hypoplasia, ectopic bronchi, glossoptosis, airway obstruction
- Aspiration = common
- Vertebtal/skeletal anomalies 20-50% -Higher risk: cleft lip, duodenal atresia
Presentation of TEF
- Polyhydramnios: 85% in isolated EA, 32% TEF -Antenatal U/S not reliable: false-pos 50%
- At birth: frothing, choking, cyanotic spells despite oral sxn -Birth weight, other anomalies important for prognosis
- Attempt to pass OG-tube → CXR = coiled in esophagus -Presence/absence bowel gas → +/- TEF
- ECHO to r/o anomalies incl right Ao arch
Long term complications of TEF
-Tracheomalacia common - “brassy” TEF cough a feature -Recurrent aspiration common - look more missed laryngeal cleft -17% fundoplication for severe reflux, 25% dysphagia at 2-years
-Long-term outcomes good.
Early mortality related to other anomalies
2 groups of abnormalities for Congenital Disease of the Systemic Arterial Tree
1) Vascular Rings
a) Right arch with left ligamentum arteriosum / PDA
b) Double AO Arch
c) Anomalous innominate or left carotid
d) Aberrant right subclavian
e) PA Sling (AKA Left PA from Right +/- crossover from left-PA supplying RUL)
2) Abn collaterals from the Ao supplying CTM or Normal lung
- More common in absent PA, and/or may be part of a complex PAVM
Characteristics of Scimitar Syndrome
= small right lung → cardiac dextroposition,
abn shadow representing abn venous drainage to systemic veins.
Genetic association with Alveolar Capillary Dysplasia
FOXF1 mutation
Misaligned lung vessels → failure of capillaries to grow in appropriate # / location
Misaligned vessel = Abnormally sited pulmonary veins
Rare cause of severe hypoxemia, resp distress and pulmonary HTN
Characteristics of Pulmonary AVMs
=direction cnxn between a PA and PV
Etiology: Many assoc. w/ HHT (AD genetic d/o assoc / epistaxis, telangiectasia, visceral AVMS) -HHT1 = endoglin (ENG) mut; HHT = ACVRL1 (ALK-1) mut
Pres: cyanosis, dyspnea, clubbing or complicatn (hemoptysis, neuro = TIA/stroke/abscess)
Lower lobe 60%, Single 60%, Unilat 75%. Single feeding artery w single draining vein 80%
Numerous communications or diffuse PAVMs possible
Diagnosis: Document R→L shunt. Screen: Contrast Bubble ECHO = primary. (Pc99m lung perfusn scan used prev). -Diagnosis confirmed via CT Angio
Embolization for PAVMs >3mm by IR
Primary vs Secondary Pulmonary Lymphangiectasia
1) Primary = either limited to lung, or involving whole body High assoc. w/ other abn: asplenia, cardiac anom
2) Secondary = due to obstruction of either lymphatic system or pulmonary veins -Causes severe resp distress - often fatal in neonatal period - but milder cases descbd
Characteristics of Congenital Diaphragmatic Hernia (Bochdalek’s)
Pathologic Anatomy: 80% left-sided via pleuroperintoneal canal. B/L rare. -Defect w/n diaphragm itself, diaphragm may be developed or deficient, -Usu no membranous sac, present in 10-15%
-Intestine, stomach, spleen, liver may all herniate.
Differential Dx: extensive congenital cystic lung dz, Morgagni anterior hernia, paraesophageal hiatus hernia, eventration
- Long-term: GI, Resp, FTT problems 2° to REFLUX and oromotor dysfxn common. -Lung fxn: Variable: Nrml, Obstructive, Restrictive or mixed. V/Q scans abn
- Bronchial hyper-reactivity common - more related to distal a/w dysfxn than inflammation
Characteristics of Anterior Diaphragmatic Hernia (Morgagni Hernia)
Herniation through foramen of morgagni -Rarer. Do not typically present as neonates.
-Usually bilateral. IF unlateral R>L. Almost always assoc with hernial sac.
-Assoc with Cardiac Anom. Assoc with pentalogy of Cantrell.
-Principles of repair = same. Defect generally smaller - therefore sutures > patch. -Outcomes: Excellent. Determined by any other anomalies.
Long-Term: mild airflow obstructn, bronchial hyper-reactivity. Chest wall asym, scoliosis.
Characteristics of Diaphragmatic Eventration:
- Congenital (rare) - from incomplete development of muscular portion of diaphragm or its innervation
- More common on Left.
- Described in fetal rubella, congenital CMV
- Assoc anomalies: rib, cardiac, renal ectopia, exomphalos
- Acquired (most often due to phrenic nerve injury - instrumental delivery, chest tube or cardiac sx)
- Assoc w/ Erb’s palsy
- Presentation: Usu by chance on CXR.
- Diagnosis: Confirmation w/ U/S = paradoxical movement of diaphragm
- Treatment: usu none. If large repair followed by plication.
Features for risk of malignant transformation of CPAM to PPB
Bilateral CTM
Type 4 CTM (~10%)
Family history of PPB, lung cysts or renal anomalies
Close relative with childhood malignancy (especially Wilm’s or medulloblastoma)
Heterozygous germline mutation in DICER1
