Israel Medical Association Journal

Background: Decreased heparan sulfate proteoglycan content of the glomerular basement membrane has been described in proteinuric patients with diabetic nephropathy. Heparanase is an endo-b-D-glucuronidase that cleaves negatively charged heparan sulfate side chains in the basement membrane and extracellular matrix.

Objectives: To investigate whether urine from type I diabetic patients differs in heparanase activity from control subjects and whether resident glomerular cells could be the source of urinary heparanase.

Methods: Using soluble ³⁵S-HSPG[1] and sulfate-labeled extracellular matrix we assessed heparanase activity in human glomerular epithelial cells, rat mesangial cells, and urine from 73 type I diabetic patients. Heparanase activity resulted in the conversion of a high molecular weight sulfate-labeled HSPG into heparan sulfate degradation fragments as determined by gel filtration analysis.

Results: High heparanase activity was found in lysates of both epithelial and mesangial cells. Immunohistochemical staining localized the heparanase protein to both glomeruli capillaries and tubular epithelium. Heparanase activity was detected in the urine of 16% and 25% of the normoalbuminuric and microalbuminuric diabetic patients, respectively. Urine from 40 healthy individuals did not posses detectable heparanase. Urinary heparanase activity was associated with worse glycemic control.

Conclusion: We suggest that heparanase enzyme participates in the turnover of glomerular HSPG. Hyperglycemia enhances heparanase activity and/or secretion in some diabetic patients, resulting in the loss of albumin permselective properties of the GBM[2].

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[1] HSPG = heparan sulfate proteoglycan

[2] GBM = glomerular basement membrane

Background: Concomitant bacterial and viral infection is a well-known phenomenon, however only very rarely has a bacterial infection been reported during hepatitis A virus infection.

Objective: To evaluate retrospectively the clinical records of children hospitalized with HAV infection for a concomitant infection proved or presumed to be bacterial.

Method: A retrospective study was conducted on all the children hospitalized with hepatitis A infection from 1988–96 in our center. The records were evaluated for a concomitant infection.

Results: Of 40 children hospitalized with HAV infection, 13 were found to have a concomitant infection: these included 6 with pneumonia, 4 with pyelonephritis and 1 case each of purulent otitis media, osteomyelitis and staphylococcal bacteremia.

Conclusion: In areas where hepatitis A is endemic, a simultaneous infection with hepatitis A and other common bacterial infection during childhood may co-exist. A permissive role for HAV infection is suggested.

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HAV = hepatitis A virus