A case of psoriasis with ANCA-negative pauci-immune crescentic glomerulonephritis in children

A potential pathogenic role of interleukin-6 in a child with ANCA-negative pauci-immune crescentic glomerulonephritis: case report and literature review

Background

Crescentic glomerulonephritis is a disease characterized by severe glomerular injuries that is classified into five different pathological types. Patients with type V disease have pauci-immune crescentic glomerulonephritis (PICGN) that is negative for anti-neutrophil cytoplasmic autoantibodies (ANCAs). There are limited clinical data on the manifestations, treatment, and prognosis of type V crescentic glomerulonephritis, especially in children.

Case presentation

A 13-year-old girl who had an intermittent fever for more than 10 months was admitted to our hospital. She had no gross hematuria, oliguria, edema, or hypertension, but further tests indicated a decreased glomerular filtration rate, hematuria, proteinuria, and an elevated level of IL-6. The antinuclear antibody spectrum test was positive at 1:1000, and the ANCA and anti-glomerular basement membrane antibody tests were negative. A renal biopsy confirmed the diagnosis of ANCA-negative PICGN. We administered methylprednisolone pulse therapy with intravenous cyclophosphamide and oral mycophenolate mofetil. At the 3-month follow-up, her urine protein level was significantly lower, and her serum creatinine level was in the normal range.

Conclusions

Fever may be an extrarenal manifestation of ANCA-negative PICGN, and IL-6 may play a role in the pathogenesis of this disease. Early methylprednisolone pulse therapy with an immunosuppressant may reduce symptoms and improve prognosis.

Severe psoriasis presenting with rapidly progressive (crescentic) IgA-predominant glomerulonephritis

IgA nephropathy (IgAN) is commonly associated with psoriasis; however, psoriasis presenting with crescentic IgAN is uncommon. A 49-year-old man with erythrodermic psoriasis with arthritis and stage 2 chronic kidney disease presented to the emergency department with worsening peripheral oedema and difficulty breathing. The patient had been hospitalised previously for a psoriasis flare. He was found to have an acute kidney injury on chronic kidney disease and was diagnosed with crescentic IgA glomerulonephritis on his first hospitalisation. He was treated with corticosteroids and was discharged stable with a plan to start cyclophosphamide in the outpatient setting. On his current hospitalisation, cyclophosphamide was added to his corticosteroids. Crescentic IgAN is rare. Its management has been based largely on observational studies. Our case highlights the importance of starting combined corticosteroids and cyclophosphamide early in crescentic IgAN and that corticosteroid monotherapy is insufficient in controlling disease progression.