How to Manage Henoch-Schönlein Purpura with Crescentic Glomerulonephritis

Henoch-Schönlein purpura (HSP) associated with crescentic glomerulonephritis is a rare but serious condition that affects the kidneys as a complication of systemic vasculitis. This autoimmune disorder typically begins with characteristic skin purpura, often accompanied by joint pain, abdominal discomfort, and kidney involvement. When renal complications arise, patients may present with hematuria (blood in urine), proteinuria (excess protein in urine), or even elevated serum creatinine levels indicating impaired kidney function.

Understanding the Diagnosis

A definitive diagnosis usually requires a kidney biopsy, which reveals hallmark pathological features such as IgA-dominant immune deposits in the glomeruli—consistent with IgA nephropathy. In more severe cases, the biopsy shows cellular crescents forming in the Bowman's space, leading to the classification of crescentic glomerulonephritis. The presence of crescents indicates aggressive inflammation and potential rapid progression toward kidney failure if left untreated.

Key Clinical Features

Patients with this dual diagnosis often experience a combination of systemic and renal symptoms. Skin manifestations include palpable purpura, typically on the lower extremities. Gastrointestinal involvement might cause colicky abdominal pain or even gastrointestinal bleeding. Joint involvement leads to transient arthritis, primarily affecting large joints. However, it's the renal component—ranging from mild urinary abnormalities to full-blown nephritic syndrome—that demands urgent medical attention.

Treatment Strategies

The management of HSP-related crescentic glomerulonephritis focuses on suppressing the overactive immune response and minimizing further kidney damage. Early intervention is crucial to preserve renal function and prevent end-stage kidney disease.

Role of Corticosteroids and Immunosuppressants

Glucocorticoids, such as prednisone or intravenous methylprednisolone, are typically the first-line therapy. They help reduce inflammation and control immune system activity. For patients with significant crescent formation or rapidly declining kidney function, a combination approach using cyclophosphamide is often recommended. This potent immunosuppressive agent has been shown to improve long-term renal outcomes in severe cases.

In cases where cyclophosphamide is contraindicated or not well tolerated, alternative agents like cyclosporine or tacrolimus may be considered. These calcineurin inhibitors modulate T-cell activity and have demonstrated efficacy in stabilizing proteinuria and preserving glomerular filtration rate.

Supportive Care and Monitoring

Beyond immunosuppression, supportive measures play an essential role. Blood pressure control using ACE inhibitors or ARBs not only manages hypertension but also reduces proteinuria and provides renoprotective effects. Regular monitoring of kidney function, urine analysis, and serological markers helps assess treatment response and detect relapses early.

Prognosis and Long-Term Outlook

The prognosis varies widely depending on the extent of crescent formation and baseline kidney function at diagnosis. Patients with less than 50% crescents on biopsy generally have a better outcome, while those with diffuse crescents face higher risks of chronic kidney disease. With timely and aggressive treatment, many patients achieve remission, though lifelong follow-up is often necessary to monitor for late complications.

In summary, managing Henoch-Schönlein purpura with crescentic glomerulonephritis requires a multidisciplinary approach involving rheumatology, nephrology, and sometimes pediatric specialists. Prompt recognition, accurate diagnosis through biopsy, and tailored immunosuppressive therapy significantly improve patient outcomes and quality of life.