20), when the forecasting incidences of PVST in nonfibrosis controls, fibrotic rats without anticoagulation, and fibrotic rats with anticoagulation were 1% , 40% , and around 10% , respectively.
Incidence and Distribution of PVST after Splenectomy.
Of the 7 cases of PVST in Splenectomy group II, there were 5 in the splenic vein and 2 in the portal and splenic veins.
Although the pathogenesis of PVST following splenectomy is still controversial, it is generally agreed that it is related to blood hypercoagulability , hemodynamic changes of the portal venous system , local vascular pathological changes , and irrational use of coagulants , and so forth.
The optimal timing for PVST to detect a vaccine response generally is 1-2 months after the final dose of the HepB vaccine series (1).
In developing this update to shorten the interval for PVST to age 9-12 months, CDC subject matter experts reviewed the shortened interval with professionals from academia and public health and considered existing (8) and new data (9) on anti-HBs levels among infants born to HBsAg-positive mothers.
For most infants born to HBsAg-positive mothers, PVST at age 9-12 months provides opportunities for testing at two well-child visits (i.
In light of the lower measured anti-HBs levels (but continued protection) with increasing time following vaccination, PVST occurring at increasing intervals after the final vaccine dose could result in misclassification of some infants as vaccine nonresponders and therefore lead to unnecessary revaccination (9).
Of the 2,683 infants with reported PVST dates and results, 114 remained susceptible after initial vaccination and PVST.
PVST identifies infants who are protected, remain susceptible after a primary HepB series, or develop HBV infection and should be referred for continuing medical care (4-6).
Among infants born to HBsAg-positive mothers and managed by perinatal hepatitis B prevention programs in the United States, and who received >3 HepB doses, PVST rates by age 15-27 months increased from 25% in 1994 to 56% in 2008 (1).
born, or had a household income <$15,000 were less likely to receive PVST (6,10).