Pediatric Antinuclear Antibody Negative Full-House Nephropathy: A Clinical Conundrum

Lupus nephritis is common in pediatric systemic lupus erythematosus (SLE). The presence of full-house immunoglobulin deposits is a unique feature for histopathological diagnosis in lupus nephritis. Our case report highlights two cases with antinuclear antibody (ANA) negative full-house nephropathy (FHN), their clinical phenotypes and intermediate long-term renal outcome. A review of the pediatric literature on this clinical entity ensued.

Two girls, aged three and nine years old presented with acute onset of kidney impairment. One needed temporary dialysis support. Both showed hypocomplementemia and biopsies concurred with FHN. Notably, ANA was absent in both patients. They achieved complete remission soon after introducing immunosuppressive therapy and the disease remained quiescent for many years thereafter. ANA remained negative during surveillance.

There have been reports on a possible incomplete form when the characteristic of FHN is seen in isolation. Although natural history of this entity remains uncertain, most literature reports apparent long-term remission following the initial episode. ANA positivity, as an obligatory criterion of diagnosing lupus nephritis (LN), recommended in the new EULAR/ACR 2019 guideline, may raise many uncertainties for this group of patients. There is a need to elucidate whether this should continue to be perceived as part of a lupus continuum or it may be considered a unique clinical entity? Such uncertainties possibly subject the child and his/her caregivers to perpetual mental stress.