Summary
Neonatal renal vein thrombosis (RVT) is a well-recognized clinical entity which is
associated with serious morbidity. However, current information regarding RVT has
been restricted to case reports and small case series. In this study, it was our objective
to describe patient demographics, clinical presentation, location and risk factors
of RVT. For our study design, we looked at a case series of 72 neonates with RVT referred to the 1-800-NO-CLOTS consultation service
between 9/1996 and 8/2001. Data on age, gender, associated conditions, prothrombotic
disorders, family history, location of the thrombosis, diagnostic techniques, and
treatment were prospectively recorded using a standardized form. Our results show
that RVT affected males (65%, CI 52-76%) significantly more often than females (35%,
CI 24-48%). Median age at presentation was 2 days (0-21 days). RVT was unilateral
in 72% (left side: 67%, CI 49-81%; right side: 33%, CI 19-51%), and bilateral in 28%.
The majority (83%) had at least one associated condition: Prematurity (54%), central
venous lines (17%), a diabetic mother (13%), asphyxia (6%), infections (6%). Prothrombotic
testing was performed in 21 neonates. Activated protein C resistance was found in
8 children (38%), other defects in three. This is the largest case series of neonatal
RVT to date. Data from the study show that i) male infants are affected twice as often
as females and ii) there appears to be a left-sided predominance of neonatal RVT.
Neonatal RVT is only infrequently associated with the presence of a catheter as compared
to thrombosis at other sites. The majority of infants have associated conditions with
prematurity being most frequent. A small subset of neonates were screened for prothrombotic
abnormalities and 50% of the children screened were positive.
Keywords
Clinical/epidemiological studies - neonates - thrombosis