Electron microscopy in end stage renal disease: a case of Fabry's disease.

Fabry's disease is an X-linked error of metabolism with deficiency of the enzyme α-glycosidase A, and glycosphingolipid accumulation in multiple tissues. Patients may be asymptomatic and present with advanced disease. We report a case of a 38 year old white male who presented with end stage renal disease of unknown etiology. He received a living-related donor kidney transplant (mother), but lost the graft after 10 years to multiple episodes of rejection. Review of the native renal biopsy with added ultrastructural studies established the diagnosis of Fabry's disease. Evaluation of renal biopsies showing advanced chronic injury should include electron microscopic studies, which may reveal characteristic diagnostic features, as seen in this case of Fabry's disease. Identification of hereditary disorders involving the kidney is important for appropriate treatment and prevention of disease recurrence. Potential living related donors should be screened for genetic involvement.

ADAMTS13 activity and inhibitor.

Thrombotic thrombocytopenic purpura (TTP) is often associated with acquired or congenital deficiency of the von Willebrand factor-cleaving metalloprotease, ADMATS13 (Lammle B et al., J Thromb Haemost 2005;3:1663-1675; Schneppenheim et al., Blood 2003;101:1845-1850). Although undetectable levels of enzyme activity (<10%) are diagnostic of inherited or acquired TTP in the correct clinical setting (absence is specific), not all patients diagnosed with TTP have severe protease deficiency, and it is therefore not recommended as an initial test for diagnosis (Copelovitch and Kaplan, Pediatr Nephrol, in press). Many prospective and retrospective studies have demonstrated that patients with severe protease deficiency have a higher likelihood of relapse, making it helpful as an indicator of recurrence. The short-term prognostic usefulness of ADAMTS13 testing during acute TTP warrants further investigation because of limited prospective studies (Ferrari S et al., Blood 2007;109:2815-2822; Peyvandi et al., Haematologica 2008;93:232-239).