gms | German Medical Science

History: A 39-year-old female with SLE on hydroxychloroquine presented at our clinic for a routine check-up. In recent years she was clinically asymptomatic and stable low-grade thrombocytopenia was the only relevant abnormality. SLEDAI-2K during most visits had a score of 0, indicating inactive disease and just intermittently reached a score of 1.

Leading symptom during disease manifestation: The patient reported feeling well, and the physical examination was unremarkable.

Diagnostics: Upon examination, the urine showed significant proteinuria and A3 albuminuria in protein/albumin-to-creatinine-ratio (uPCR 724 mg/g, uACR 488 mg/g). IgG/creatinine was markedly elevated (74.4 mg/g), and α1-microglobulin was normal, indicating nonselective glomerular proteinuria without tubular impairment (Table 1 [Tab. 1]). APC was stable (108 G/l). There were no other abnormalities suggestive of SLE activity.

Further course: After she recalled having vaginal spotting a week earlier, a pregnancy test was performed with a positive result. Subsequently, the βHCG level increased inappropriately. Ultrasound detection failed to detect a live embryo, but the intrauterine presence of two amniotic cavities was suspected. An early incomplete miscarriage was diagnosed, and gestational age was calculated to be 6+5 weeks. Shortly thereafter, a planned suckling curettage was performed. One week later, she had a final vaginal bleed. At this time, the urine showed a decrease in proteinuria by over 50% (uPCR 317 mg/g, uACR 210 mg/g, IgG 26.9 mg/g). Three weeks later, urine protein was completely normalized, which proved stable 12 weeks after initial diagnosis. Throughout the follow-up, she did not show any SLE relapse. After exclusion of differential diagnoses (Fig. 1 [Fig. 1]), causality of the miscarriage with the urinary findings seems evident. To date, there have been no reports of concomitant occurrence of early pregnancy miscarriage, possibly lupus nephritis (LN)-indicative glomerular proteinuria, and its spontaneous regression in a clinically and serologically inactive SLE patient. Recently, observations were confirmed that a large proportion of patients with a uPCR <1 g/g had LN histology, whereas several had inactive sediment or normal serology like our patient. As the kidney is the organ most affected in SLE pregnancy, it is important to be aware of intermittent proteinuria, as the consequences may be very different from persistent proteinuria as would be expected in nephritis.