Clinical, morphologic, and genetic features of renal leukocyte chemotactic factor 2 amyloidosis.

Leukocyte chemotactic factor 2 amyloidosis (ALECT2) is a recently described form of amyloidosis that most frequently manifests clinically with progressive renal failure. In a series of 414 cases of amyloidosis, there were 40 cases of ALECT2: the second most common type of renal amyloidosis in this series. This was particularly common in Hispanic patients in the Southwest United States, where more than half of amyloidosis cases were ALECT2. It is possible that this represents a familial amyloidosis as there were two brothers with ALECT2 in our study. Morphologically, there was consistent amyloid deposition in the renal cortex with medullary involvement in only about a third of cases. There were no mutations detected in the LECT2 gene, although all patients tested were homozygous for the G nucleotide in a non-synonymous SNP at position 172. Most patients presented with chronic kidney disease and, on follow-up, showed progression with an average deterioration in renal function of 0.5 ml/min/1.73 m(2) per month. Unfortunately, the etiology of ALECT2 is currently unknown and there is currently no efficacious treatment of the disease.