Clinical Profile of Primary Sjogren's Syndrome with Hypokalemic Periodic Paralysis.

Introduction: Primary Sjogren's Syndrome (pSS) with Hypokalemic Periodic Paralysis(HPP) whether an association or a different clinical subset needs review.

Methods: Cross-sectional retrospective study of subjects of Primary Sjogren's Syndrome with Hypokalemic Periodic Paralysis(HPP) identified from database maintained at Centre For Rheumatic Diseases, Pune since 1996 with records of over 50000 patients. The diagnosis was clinical. Clinical and investigations data was extracted pertaining to initial examination and follow up. Standard investigations & ELISA, immunoblot and nephelometry to assay autoantibodies (AAb) were done.

Results: 16 patients of Primary Sjogren's Syndrome (pSS) with Hypokalemic Periodic Paralysis (HPP) were identified in the period 2000-2014. Presenting feature was HPP in 86% with Dry eye (4%) and Arthralgias (10%) in remaining. Distal Renal Tubular Acidosis was identified in all. All were females with average age of 26 years. Symptomatic ocular sicca noted in 60% & Oral sicca in 50% patients. Other features - Arthralgias (91%), arthritis (42%), mucositis (38%), Neuropathy (30%), skin rash (20%) cytopenias (19%), Erosive arthritis (10%), interstitial lung disease (10%) and Raynaud Phenomenon (10%). 100% were positive for ANA. SSA was positive in 100%, SSB in 50% of patients & Rheumatoid Factor in 70 %. Hypothyroidism was associated in 70% patients.

Conclusion: We present a large series of Primary Sjogren's Syndrome with Hypokalemic Periodic Paralysis(HPP) from India. Prominent features of female dominance, younger age of onset and SSA positivity noted in this cohort of patients on Routine clinical and serology phenotype suggests existence of a distinct subset. HPP was presenting feature in majority.