Extremely high levels of alkaline phosphatase and pregnancy outcome:
case series and review of the literature
Objective: To evaluate the association between extremely elevated
alkaline phosphatase (ALKP) levels (above 1000 U/L) and adverse
perinatal outcome. Design: A retrospective case series Setting and
popultion: All parturients with extremely elevated ALKP levels taken
throughout pregnancy at a single university-affiliated medical center
(2010-2018). Methods: Demographics and medical data were retrieved.
Following literature review, previously reported similar cases were
added to the cohort. We report perinatal outcome of our cohort as well
as literature review. Results: During study period 11 parturients with
high ALKP were identified. Ten more cases were retrieved from PubMed
search. Overall, median ALKP levels were 1880 (range 1052-4488, U/L).
Reasons for evaluation were mostly nonspecific symptoms (pruritus,
headache, abdominal pain) or routine obstetrical evaluation. Twelve
isoenzyme analysis were available - 10 of which were of placental
fraction; median gestational age at delivery was 38 (35-41), four (19%)
women delivered preterm, ; six patients (29%) had gestational diabetes
mellitus and 6 (29%) had hypertensive disorder. Histopathology of the
placenta was available in 8 cases: 3 normal histology (38%) and 5 with
different non-specific pathologies. Conclusions: We report the largest
case series of extremely elevated levels of ALKP in pregnancy thus far.
Our data suggest association with adverse perinatal outcome.