These results suggest that increased anti-zymogen antibody titers are the best available marker for streptococcal infection associated with acute glomerulonephritis.

Shiga toxin (Stx)-producing Escherichia coli (STEC) infection is associated with a broad spectrum of clinical manifestations that include diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Systemic Stx toxemia is considered to be central to the genesis of HUS. Distinct methods have been used to evaluate anti-Stx response for immunodiagnostic or epidemiological analysis of HUS cases. The development of enzyme-linked immunosorbent assay (ELISA) and western blot (WB) assay to detect the presence of specific antibodies to Stx has introduced important advantages for serodiagnosis of HUS. However, application of these methods for seroepidemiological studies in Argentina has been limited. The aim of this work was to develop an ELISA to detect antibodies against the B subunit of Stx2, and a WB to evaluate antibodies against both subunits of Stx2 and Stx1, in order to analyze the pertinence and effectiveness of these techniques in the Argentinean population. We studied 72 normal healthy children (NHC) and 105 HUS patients of the urban pediatric population from the surrounding area of Buenos Aires city. Using the WB method we detected 67% of plasma from NHC reactive for Stx2, but only 8% for Stx1. These results are in agreement with the broad circulation of Stx2-expressing STEC in Argentina and the endemic behavior of HUS in this country. Moreover, the simultaneous evaluation by the two methods allowed us to differentiate acute HUS patients from NHC with a great specificity and accuracy, in order to confirm the HUS etiology when pathogenic bacteria were not isolated from stools.

These results indicate that Mo from severe cases of HUS, similar to IC but different to mild HUS cases, present functional changes in Mo subpopulations and abnormal responses to LPS.

Renal disease concurrent with a Mycoplasma pneumoniae infection is uncommon. In this report we describe the clinical outcome of a 6-year-old patient who presented with a rapidly progressive glomerulonephritis that required dialysis. A kidney biopsy was performed, and the results revealed membranoprolipherative glomerulonephritis. The IgM serology was positive, and M. pneumoniae DNA was detected in a renal biopsy sample using a nested-PCR assay. The outcome was good.