Neonatal Lupus

Question 1

Anti-Ro60/Trove2

Answer 1

60-kD polypeptide

• Ro60 protects the cell from damage from UV
• play a role in RNA quality control
• May protect against the development of autoabs by sequestering defective RNPs
• Can appear on the cell surface during stress or apoptosis and therefore be a direct target for autoantibodies

Question 2

Anti La/48

Answer 2

Can appear on the cell surface during stress or apoptosis and therefore be a direct target for autoantibodies
- Not a good screening tool alone

Question 3

Anti Ro 52/Trim 21

Answer 3

Catalyzes the ubiquitination of
several proteins including Ro 52 itself
- Regulates of proinflammatory cytokine production
- The production of type I ifn and cytokine via its ubiquitination of IRF
- Regulation of innate immune response to dsDNA
- Modulation of follicular b cell homeostasis and IG production
- Less sensitive but more specific (found in 70-100 percent of mothers of children with CHB

Question 4

Autoantibodies to test for in NLE

Answer 4

• Anti Ro60
• Anti Ro52
• Anti La 48
• Anti U1RNP

Question 5

Most common autoimmune diseases present in a mother of a child with NLE

Answer 5

SS
SLE
UCTD

Question 6

Genes important for the production of anti-Ro and anti-La antibodies

Answer 6

HLA DR

HLA DQ

Question 7

Genes associated with anti Ro52 and anti La48

Answer 7

HLA DR3

Question 8

Risk factors for CHB

Answer 8

Mother with high anti-Ro Titers who already had a child with CHB (risk rises from 1 to 5% to 18-25%)

Question 9

Characteristic pathological finding

Answer 9

Absence of degeneration of the AV node with or without the bundle of HIS with replacement by fibrosis and calcification

Question 10

Risk factors associated with perinatal mortality

Answer 10

• Earlier gestational age at CHB diagnosis
• fetal hydrops
• myocarditis
• EFE
• CHB with a heart rate less than 50 bpm

Question 11

Treatments for NLE (mother)

Answer 11

• Dexamethasone for second or third degree heart block without EFE, EFE, or EFE with any degree of heart block
• Maternal IVIG if there is evidence of myocarditis, EFE or incomplete AV block
• High dose maternal beta 1 adrenergic stimulation is used when fetal heart rates are below 50 bpm or when there is significantly reduced cardiac contractility

Question 12

Treatments for NLE (Baby)

Answer 12

• Pulse for neonates with myocarditis/EFE
• A trial of red for neonates with second degree heart block, those who were in CHB in utero and showed signs of improvement and or those who had evidence of myocarditis/EFE on pre or post natal cardiac US

Question 13

Why is the rash of NLE more common in females?

Answer 13

Estrogen increases surface expression of Ro an LA on keratinocytes

Question 14

Rash associated with NLE

Answer 14

• Resembles lesions of SCLE, less malar , less indurated\
• Face and scalp are the most commonly involved areas but it can be anywhere including palms and soles
• Can see raccoon eye distribution
• Can be present at birth but more commonly develops within the first few weeks of life
• rarely develop after 6 months