Chronic Histiocytic Intervillositis (CHIV) is a rare inflammatory disorder affecting the placenta, the organ responsible for supplying oxygen and nutrients to a developing fetus. This condition can interfere with the placenta’s normal function. Understanding CHIV is important for individuals who have experienced adverse pregnancy outcomes linked to placental issues.
Understanding Chronic Histiocytic Intervillositis
The term “chronic” in Chronic Histiocytic Intervillositis indicates that the inflammatory process develops over an extended period. “Histiocytic” refers to histiocytes, a type of macrophage involved in immune responses and clearing cellular debris.
“Intervillositis” points to the inflammation’s location within the placenta, specifically the intervillous space. This area is where maternal blood circulates around the fetal villi, facilitating the exchange of gases, nutrients, and waste products between the mother and the fetus. In CHIV, there is an abnormal accumulation of maternal histiocytes within this space.
The precise cause of Chronic Histiocytic Intervillositis remains largely unknown. However, it stems from an atypical maternal immune response directed against the placenta. This leads to persistent inflammation in the intervillous space, disrupting placental health.
Impact on Placental Function and Pregnancy Outcomes
Chronic Histiocytic Intervillositis significantly impairs the placenta’s ability to perform its functions. The accumulation of inflammatory cells within the intervillous space impedes the transfer of oxygen and nutrients from the mother’s blood to the fetal circulation. This reduced exchange can affect fetal growth and development.
A frequent adverse outcome associated with CHIV is fetal growth restriction (IUGR). This occurs when the fetus does not grow at the expected rate due to insufficient nutrient supply from the compromised placenta. Babies with IUGR may be born smaller than average, facing potential health challenges.
Placental dysfunction caused by CHIV can lead to complications, including preterm birth, where the baby is born before 37 weeks of gestation. Oligohydramnios, a condition characterized by low levels of amniotic fluid surrounding the fetus, may also develop. In severe instances, the compromised placental function can result in stillbirth or neonatal death.
Diagnosis and Identification
Chronic Histiocytic Intervillositis is typically diagnosed following an adverse pregnancy outcome rather than during pregnancy. This is because mothers do not experience specific symptoms during pregnancy. Diagnosis relies on a histopathological examination of the placenta after delivery.
During this examination, a pathologist carefully analyzes tissue samples from the placenta under a microscope. Findings indicative of CHIV include the accumulation of maternal histiocytes within the intervillous space, often accompanied by fibrin deposition. These observations confirm chronic inflammation.
A placental examination may be recommended in situations like recurrent pregnancy losses, severe fetal growth restriction, or unexplained stillbirths. This analysis helps determine the cause of previous complications, aiding future reproductive planning.
Management and Planning for Future Pregnancies
Management strategies for subsequent pregnancies in individuals with a history of Chronic Histiocytic Intervillositis often involve close medical monitoring. There is no universally established treatment, but interventions aim to modulate the maternal immune response or improve placental blood flow. Corticosteroids may be prescribed to suppress the immune system’s activity.
Anticoagulants may be considered to prevent blood clots within the intervillous space. Effectiveness varies, and their use is based on individual consideration of benefits versus risks. These interventions are part of an individualized treatment plan.
Given the risk of recurrence in future pregnancies, preconception counseling is recommended for individuals with a history of CHIV. This allows discussion of risks and management strategies before conception. Throughout subsequent pregnancies, close antenatal surveillance, including frequent ultrasound scans to monitor fetal growth and amniotic fluid, is implemented to detect issues early.