gms | German Medical Science

Introduction: Lupus nephritis (LN) occurs in more than half of patients with systemic lupus erythematosus (SLE) and is associated with end-stage renal disease (ESRD) and increased mortality. Although males only comprise one fifth to one tenth of all SLE patients, previous studies suggest more severe cardiovascular and hematological involvement in this sub-group, as well as more renal affection and progression to ESRD.

Methods: This is a retrospective observational study of routinely collected clinical, laboratory and histological data in patients with lupus nephritis. We aim to describe and compare the disease characteristics including serological activity, proteinuria, renal function, and histological findings between female and male LN patients.

Results: We analysed 58 patients with LN, 48 females and 10 males. Median age at LN diagnosis was 35.5 and 46.5 years, respectively. Concomitant SLE manifestations of skin lesions, alopecia and ulcers were more prevalent among female patients, while the male sub-group displayed significantly more cardiac involvement including arterial hypertension as well as thrombosis and pulmonary embolisms. Male LN patients had more pronounced complement consumption. Creatinine at the time of renal biopsy was higher in female LN patients (1.3 vs. 1.06 mg/dl), whereas the most recent available creatinine during follow-up was higher in the male group (1.52 vs. 1.32 mg/dl). Histologically, almost two thirds of the male cases were classified as LN class III (62.5%), whereas the most prevalent LN class among the female population was class IV (38.1%) followed by III (23.8%). Female LN patients displayed significantly higher levels of proteinuria at biopsy compared with their male counterparts (2099 vs. 726 mg/g creatinine). A total of 6 patients in this LN cohort required dialysis (2 intermittent, 4 chronic RRT), all of which were female.

Conclusion: Male and female SLE patients differ in key aspects of disease manifestation, activity and progression. Lupus nephritis in particular requires a more detailed analysis as it represents one of the most common end organ affections in SLE. A more in-depth analysis of renal biopsies with more emphasis on the tubulointerstitium might help understand why male and female patients differ in LN presentation and progression. Clinical differences in SLE manifestations between male and female patients should be considered, especially in the high-risk group of LN patients.

Disclosures: None declared