Common Peroneal Nerve Palsy: A Unique Complication of Nephrotic Syndrome - A Case Report

Background: Although children with nephrotic syndrome are known to present with generalized edema, entrapment neuropathy of common peroneal nerve in such conditions is unreported. Clinical Description: An 8-year-old girl presented with right lower limb wasting and foot drop developing over 4 months. There was no history of trauma, fever, or back pain. She was a known case of nephrotic syndrome, having been hospitalized 4 months ago with generalized edema and sepsis. On examination, child was afebrile and hemodynamically stable, with a high-stepping gait, reduced lower limb girth and power on the right side compared to the left. Management and Outcome: Laboratory parameters, X-ray hip and limbs, and ultrasonography of limbs were normal. Nerve conduction test showed common peroneal nerve palsy. The etiology of this nerve injury was possibly compression entrapment neuropathy resulting from tissue edema of limbs with some degree of immobilization, during the earlier hospitalization episode. The child was strapped with ankle-foot-arthosis and provided physiotherapy. He showed gradual recovery over the next 4 months. Conclusion: Limb edema even with a modest period of immobilization, during relapse in nephrotic syndrome, can cause compression entrapment neuropathy of common peroneal nerve, which manifests with foot drop and wasting, weeks after the acute injury. Early identification based on nerve conduction tests can help in starting appropriate supportive therapy resulting in complete recovery.