Inaugural complete heart block in anti-SSA negative systemic lupus erythematosus: the diagnostic role of anti-PM-Scl 100 antibodies.
Nadia Dammene Debbih, Leila Laouar, Nassima Dekdouk et al.
✦ AI-curated · Sources linked
Case in brief
A 21-year-old woman with a family history of systemic lupus erythematosus (SLE) presented with symptomatic complete heart block (CHB) at a rate of 40 bpm. Despite negative results for anti-SSA/Ro and anti-SSB/La antibodies, she tested positive for anti-PM-Scl 100 antibodies. Cardiac MRI ruled out common causes, and a dual-chamber pacemaker was implanted due to irreversible conduction failure.
What made this case unusual
This case highlights the occurrence of inaugural CHB in an anti-SSA-negative SLE patient, which is exceptionally rare and challenges the traditional association of CHB with anti-SSA antibodies.
Diagnostic / clinical pearl
Clinicians should consider the possibility of complete heart block in SLE patients even when classic anti-SSA antibodies are absent, and utilize extended antibody profiling.
Why it matters
This case underscores the importance of integrating nailfold capillaroscopy and comprehensive antibody testing in diagnosing atypical autoimmune presentations, potentially improving patient outcomes.