Monitoring Anti-Pythium insidiosum IgG Antibodies and (1->3)-β-D-Glucan in Vascular Pythiosis

Worasilchai, N.; Permpalung, N.; Chongsathidkiet, P.; Leelahavanichkul, A.; Mendoza, L. A.; Palaga, T.; Reantragoon, R.; Finkelman, M. A.; Sutcharitchan, P.; Chindamporn, A.

doi:10.1101/300764

bioRxiv · 10.1101/300764

Monitoring Anti-Pythium insidiosum IgG Antibodies and (1->3)-β-D-Glucan in Vascular Pythiosis

Worasilchai, N.·Permpalung, N.·Chongsathidkiet, P.·Leelahavanichkul, A.·Mendoza, L. A.·Palaga, T.·Reantragoon, R.·Finkelman, M. A.·Sutcharitchan, P.·Chindamporn, A.

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Abstract

BackgroundDespite aggressive treatment, vascular pythiosis has a mortality rate of 40%. This is due to the delay in diagnosis and lack of effective monitoring tools. To overcome this drawback, serum beta-D-glucan (BG) and P. insidiosum specific antibody (Pi-Ab) were examined as potential monitoring markers in vascular pythiosis.\n\nMethodsA prospective cohort study of vascular pythiosis patients was carried on during January 2010-July 2016. Clinical information and blood samples were collected and evaluated by the BG and Pi-Ab assays. Linear mixed effect models were used to compare BG and Pi-Ab levels. The in vitro susceptibility test was performed in all P. insidiosum isolates from culture positive cases.\n\nResultsA total of 50 patients were enrolled; 45 survived and 5 died during follow-up. The survivors had a significantly shorter time to medical care (p<0.0001) and a significantly shorter waiting time to the first surgery (p<0.0001). There were no differences in BG levels among the groups at diagnosis (p=0.17); however, BG levels among survivors were significantly lower than the deceased group at 0.5 months (p<0.0001) and became undetectable after 3 months. Survivors were able to maintain ELISA value (EV) of Pi-Ab above 8, whereas EV among deceased patients was less than 4. In vitro susceptibility results revealed no synergistic effects between itraconazole and terbinafine.\n\nConclusionsThis study showed that BG and Pi-Ab were potentially valuable markers to monitor the disease after treatment initiation. An unchanged BG level at 2 weeks after surgery should prompt an evaluation for residual disease.

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Worasilchai, N., Permpalung, N., Chongsathidkiet, P., Leelahavanichkul, A., Mendoza, L. A., Palaga, T., Reantragoon, R., Finkelman, M. A., Sutcharitchan, P., Chindamporn, A.. 2018-04-13. Monitoring Anti-Pythium insidiosum IgG Antibodies and (1->3)-β-D-Glucan in Vascular Pythiosis. https://doi.org/10.1101/300764

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