The hypereosinophilic syndromes (HESs) are a group of disorders marked by the sustained overproduction of eosinophils, in which eosinophilic infiltration and mediator release cause damage to multiple organs. In idiopathic HES, the underlying cause of hypereosinophilia (HE) remains unknown despite thorough aetiological work-up. Kidney disease is thought to be rare in HES. Renal manifestations described include eosinophilic interstitial nephritis, various types of glomerulopathies, thrombotic microangiopathy (TMA) and electrolyte disturbances. The diagnosis must be made in time, because a recovery of renal function can be obtained if treatment is initiated promptly.

Nonhematologic malignancies are rarely reported to be associated with AA amyloidosis. Although the association between renal cell carcinoma and systemic AA amyloidosis has been established, the evidence linking pulmonary cancer to AA amyloidosis is scarce. Here, a case of biopsy-proven renal AA amyloidosis complicated with nephrotic syndrome associated with lung carcinoma is reported.

We report a case of renal thrombotic microangiopathy (TMA) in a myeloproliferative variant of hypereosinophilic syndrome (HES) in a 24-year-old man which resolved with imatinib therapy. This is one of a few cases in the literature to date describing TMA in HES, suggesting that the pathogenesis of thrombosis is at least in part related to damage from activated eosinophils.