ANA patterns

Question 1

what antigens are targeted in a homogenous pattern, and what if there is a rim/peripheral pattern>

Answer 1

anti-DNA: anti-ssDNA and histone more for the homogenous only; and more anti-dsDNA for rim

Question 2

A high titer of anti-dsDNA (rim) is associated strongly with? what about low titer?

Answer 2

SLE; lower titer seen in MCTD, SS, RA….

Question 3

A speckled ANA is associated with what antigens and disorders?

Answer 3

it is the most common and least specific so not only SLE but also MCTD, SS, Scleroderma, CREST..

Question 4

what specific antibodies should be tested for if an ANA is positive for homogenous pattern?

Answer 4

anti-ds and ssDNA, and anti-Sm (Smith)

Question 5

anti-Sm is most specific to:

Answer 5

Lupus

Question 6

If anti-Sm and dsDNA is negative, but anti-RNP high, what is a likely diagnosis>

Answer 6

MCTD; can’t rule out Lupus if have RNP but also Sm and dsDNA

Question 7

describe the speckled pattern

Answer 7

like a haze or cloud of fluorescence with “holes of dark”, including mitoses (see two dark lines)

Question 8

the centromere and nucleolar ANA patterns are most associated with:

Answer 8

Scleroderma with CREST, or Idiopathic Raynaud’s

Question 9

what do the anti nucleolar and anti-centromere ANA patterns target antigen wide?

Answer 9

anti-nucleolar: anti-RNP

anti-centromere: anti-Scl-70 and centromere proteins like CENP-A, B, & C

Question 10

how does the nucleolar pattern differ from centromere?

Answer 10

Nucleolar has large, 2 or 3 usually, fluorescent “uneven polka dots” (anti-RNP!), mitoses negative; centromere has many many tiny fluorescent dots, and mitotic cells are positive (two fluorescent bars of dots)