Fetopathology and developmental pathology of the embryo and fetus: Hydrops fetalis

+ Introduction

+ Support

+ Atlas of fetal pathology

+ Congenital malformations of individual organ systems

Hydrops fetalis

Introduction

Hydrops fetalis is defined as generalized accumulation of fluid in a fetus. Hydrops is an end-stage process for numerous fetal diseases.

Etiology, pathogenesis

increased intracapillary hydrostatic pressure
- congestive heart failure due to severe fetal anemia, structural heart defect, arrythmia
- obstruction of cardiac venous return
- portal hypertension due to sinusoidal obstruction of the liver by excessive extramedullary hematopoiesis or storage material
decreased intracapillary oncotic pressure
- hepatic synthesis of albumin may be imparaired because of hepatic hypoperfusion, increased extramedullary hematopoisis, storage diseases and infectious injury
increased capillary permeability, endotelial damage
- endotelial damage in various infections
obstructed lymphatic flow

Macroscopic appearance

Fetální hydrops (73677)

Classification

Clinical signs

Incidence: In the past the most common cause of immune hydrops fetalis was Rh isoimmunization. Since the advent of anti-D globulin prophylaxis the incidence of immune hydrops has decreased significantly. Nowadays most cases of hydrops fetalis are nonimmune in nature. The incidence of nonimmune hydrops in Europe and the United States is approximately 1:2500 – 4000 newborns. Parvovirus B19 infection, fetomaternal transfusion and twin-to-twin transfusion are quite common. The indicence of hydrops fetalis, up to 1:500 pregnancies, is very high in the Southeast Asia as a consequence of homozygous α thalassemia.
Prognosis: General mortality of hydrops fetalis is 60 – 90%. Stillbirth is frequent. The cause of death of a hydropic infant is respiratory insuficiency due to pulmonary hypoplasia.

Pictures

Nonimmune hydrops

Hygroma colli cysticum