A speckled pattern in the indirect fluorescent anti-nuclear antibody test may indicate the presence of which antibodies?

A speckled pattern observed in the indirect fluorescent anti-nuclear antibody test is typically associated with the presence of anti-Smith (anti-Sm) antibodies. These antibodies are highly specific for systemic lupus erythematosus (SLE) and indicate an autoimmune response. The speckled pattern occurs due to the binding of these antibodies to protein components within the nucleus, leading to a characteristic fluorescence pattern.

In the context of other antibodies mentioned, while anti-DSDNA antibodies often result in a homogenous pattern, anti-histone antibodies can sometimes show a similar speckled pattern, particularly in drug-induced lupus cases. However, anti-Smith antibodies are particularly noted for their speckled appearance and association with SLE, which is why they are the most recognized in this context.