Fetopathology and developmental pathology of the embryo and fetus: Diaphragm and congenital malformations

+ Introduction

+ Support

+ Atlas of fetal pathology

+ Congenital malformations of individual organ systems

Diaphragm and congenital malformations

Introduction

The diaphragm is formed from the structures of septum transversum, body wall and pleuroperitoneal membranes.

The most important and most frequent defect is congenital posterolateral hernia located on the left. The occurence is 1 : 2000 – 3000 liveborns.

Associated congenital malformations of other organs are found in about one quarter of the affected individuals. Cardiovascular, urogenital or central nervous system malformations are associated.

Classification

posterolateral hernia (Bochdalek)occurs in 95% of the cases, located on the left in nine of ten cases. The defect is on the right or even bilateral in a small proportion of cases. The defect is a result of persistence of a pleuropulmonal canal.
anterolateral hernia (Morgagni)is retrosternal, usually a small and asymptomatic defect
diaphragmatic eventrationintact but very thin, hypoplastic diaphragm bulges into the thoracic cavity. There is an abnormal muscularization of the diaphragm. Severe involvement has the same detrimental sequelae as congenital diaphragmatic hernia.
diaphragmatic agenesis

Etiology

Often occurs with chromosomal aberrations (trisomy 18,21) Nevertheless most cases are sporadic, the condition commonly presents as the sole abnormality in wellgrown term infant. Familial cases are very rare and comprise less than 2% of the cases.

Clinical signs

Through the defect of the diaphragm the abdominal organs herniate into the thoracic cavity and compress the lung. Sometimes the mediastinum is shifted. The lung on the side of the hernia is always hypoplastic but the contralateral lung may be also involved. An infant with a large hernia presents in the first minutes to hours of life with severe respiratory distress. Surgical correction of the defect is performed immediately. Survival rates are low even nowadays in infants with large or bilateral diaphragmatic defets, severe pulmonary hypoplasia and persistent pulmonary hypertension.

Congenital diaphragmatic hernia (72049)

Congenital diaphragmatic hernia (72048)

Pictures

Congenital diaphragmatic hernia: Diaphragmatic herniation, Macro, autopsy (72049) Diaphragmatic herniation, Macro, autopsy (72048)

Left sided diaphragmatic hernia, 22-week fetus: Congenital diaphragmatic herniation, Macro, autopsy (72440) Congenital diaphragmatic herniation, Macro, autopsy (72441)

Left sided diaphragmatic hernia: Diaphagmatic herniation, Macro, autopsy (73290) Diaphagmatic herniation, Macro, autopsy (73291)

Left-lung hypoplasia in congenital left diaphragmatic hernia: Congenital diaphragmatic herniation, Macro, autopsy (72442)

Right diaphragmatic herniation: Right side diaphragmatic herniation, Macro, autopsy (73267)