Serum-negative Sjogren's syndrome with minimal lesion nephropathy as the initial presentation: A case report

BACKGROUND: Primary Sjogren's syndrome (pSS) is an autoimmune disease, and renal involvement has been considered to be one of the systemic complications of pSS. Patients who have sjogren's syndrome with renal disease as the first manifestation and no exocrine gland involvement or autoantibodies can be missed clinically. CASE SUMMARY: We here in report an unusual case of a primary Sjogren's syndrome in a 43-year-old female who had minimal lesion nephropathy as the initial presentation, and the patient was negative for serum anti-SSA and anti-SSB antibodies and did not have signs of exocrine gland involvement. The patient’s Sjogren's syndrome was confirmed by a minor salivary gland biopsy (MSGB) and a filter paper test. the patient’s oedema subsided, and the patient’s urinary protein resolved, showing that the treatment was effective. CONCLUSION: MSGB should be considered if pSS is suspected in patients who do not have the typical pSS symptoms or who are positive for the specific autoantibodies.