RH Incompatibility
Clinical Manifestation
Mild Rh incompatibility:
• Positive direct Coombs
• Evidence of hemolysis in the infant’s blood
• Elevated cord blood bilirubin
Hydrops fetalis:
• Severe anemia
• Heart failure (cardiac failure)
• Enlarged liver (hepatomegaly)
• Respiratory distress
• Bruising or purplish bruise-like lesions on the skin (purpura)
Kernicterus — Early:
• High bilirubin level (greater than 18 mg/cc)
• Extreme jaundice
• Absent Moro (startle) reflex
• Poor breast-feeding or sucking
• Lethargy
Kernicterus — Mid:
• High-pitched cry
• Arched back with neck hyperextended backwards (opisthotonos)
• Bulging fontanel (soft spot)
• Seizures
Kernicterus — Late (full neurological syndrome):
• High-frequency hearing loss
• Mental retardation
• Muscle rigidity
• Speech difficulties
• Seizures
• Movement disorder
Medical Management
Since Rh incompatibility is almost completely preventable with the use of RhoGAM, prevention remains the best treatment. Treatment of the already affected infant depends on the severity of the condition.
Mild:
• Aggressive hydration
• Phototherapy using bilirubin lights
Hydrops fetalis:
• Amniocentesis to determine severity
• Intrauterine fetal transfusion
• Early induction of labor
• A direct transfusion of packed red blood cells (compatible with the infant’s blood) and also exchange transfusion of the newborn to rid the blood of the maternal antibodies that are destroying the red blood cells
• Control of congestive failure and fluid retention
Kernicterus:
• Exchange transfusion (may require multiple exchanges)
• Phototherapy
Expectations (prognosis)
Full recovery is expected for mild Rh incompatibility. Both hydrops fetalis and kernicterus represent extreme conditions caused by hemolysis. Both have guarded outcomes. Hydrops fetalis has a high mortality rate.
Reference
Davidson, Susan. Diseases Causes & Diagnosis Current Therapy Nursing Management Patient Education (Educational Publishing House. 1990)
Kumar. Robbins & Cotran Pathologic Basis of Disease (Elsevier Saunders Inc. 7th edition. 2005)
Huether. Understanding Pathophysiology (Mosby, Inc. 2nd edition. 2000)
