Linked Life Data

2393714

Source:http://linkedlifedata.com/resource/pubmed/id/2393714

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1990-10-5
pubmed:abstractText
To better estimate how frequently patients with low serum cobalamin (Cbl) levels in current clinical practice are truly deficient in Cbl and to determine the incidence of atypical or nonclassic presentations of Cbl deficiency, we prospectively studied 300 unselected consecutive patients with serum Cbl concentrations less than 200 pg/mL seen at two medical centers over a 2-year period. Baseline hematologic, neuropsychiatric, and biochemical measurements were obtained, followed by a course of parenteral Cbl therapy and reassessment. A response to Cbl therapy was defined as one or more of the following: (1) an increase in hematocrit of 0.05 or more; (2) a decrease in mean cell volume of 5 fL or more; (3) a clearing of hypersegmented neutrophilis and macroovalocytes from the peripheral blood smear; and (4) an unequivocal and prompt improvement of neuropsychiatric abnormalities. Of the 300 patients with serum Cbl levels less than 200 pg/mL, 86 had one or more responses to Cbl therapy and 59 had no response. In 155, insufficient data was available. In the Cbl-responsive patients, normal values were found for the following tests: hematocrit, 44%; mean cell volume less than or equal to 100 fL, 36%; white blood cell count, 84%; platelet count, 79%; serum lactic dehydrogenase, 43%; and serum bilirubin, 83%. Peripheral blood smears were nondiagnostic in 6% when reviewed by the investigators, but 33% as reported by routine laboratories. Serum Cbl levels in the 100 to 199 pg/mL range were present in 38%. Neuropsychiatric abnormalities were noted in 28%, often in the absence of anemia, macrocytosis, or both. Serum levels of methylmalonic acid and/or total homocysteine were elevated greater than 3 SDs above the mean for normal subjects in 94% of the Cbl-responsive patients. We conclude that Cbl deficiency should be considered and investigated in patients with unexplained hematologic or neuropsychiatric abnormalities of the kind seen in Cbl deficiency, even if anemia, an elevated mean cell volume, a marked depression of the serum Cbl, or other classic hematologic or biochemical abnormalities are lacking. Levels of serum methylmalonic acid and total homocysteine are useful as ancillary diagnostic tests in the diagnostis of Cbl deficiency.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
871-81
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Clinical spectrum and diagnosis of cobalamin deficiency.
pubmed:affiliation
Department of Medicine, University of Colorado Health Sciences Center, Denver 80262.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.