Blood, 1969, Vol. 34, No. 4, pp. 452-465.
© 1969 American Society of Hematology, Inc.
Isolated Defect of Folic Acid Absorption Associated with
Mental Retardation and Cerebral Calcification
PHILIP LANZKOWSKY 1,
MARION E. ERLANDSON 1, and
ALLAN I. BEZAN 1
1 Department of Pediatrics, Division of Pediatric Hematology, The New York
Hospital-Cornell University Medical College, New York, New York.
A 19 year old female is described with a clinical syndrome characterized by
specific malabsorption of folate from the gut with resultant megaloblastic
anemia associated with mental retardation and cerebral calcification. The
absorption of fat, xylose, glucose, vitamin A and vitamin B12 and the jejunal
biopsy histology were all normal. The patient was unable to absorb folate in
its naturally occurring form as pteroylpolyglutamic acid as well as pteroylmono-, pteroyldi-, pteroyltriglutamic acid, N5-formyltetrahydrofolic acid and
N5-methyltetrahydrofolic acid. Folate absorption was not enhanced when
pteroylmonoglutamic acid was premixed with normal human duodenal juice,
lyophilized calf jejunum or lyophilized calf pancreas. Impairment of normal
transport of folic acid from the blood into the cerebrospinal fluid was also
demonstrated in this patient. Plasma folate clearance was normal and there
was no increase in folate antagonists or in folate binding present in the
patient’s plasma.
Submitted on March 12, 1969
Accepted on May 30, 1969
