Re: hypocalciuria in hipertensive disorders
From: art fougner, md (evsono@pipeline.com)
Thu Mar 2 16:37:07 2000
Nice article in Lancet circa 1976 by Redman and Bonnar on the use of
uric acid in hypertensive disorders.
Art
At Thu, 2 Mar 2000, Efrain Ramirez wrote:
>
>Williams Obstetrics is a very nice, comprehensive text book. It is not,
>by all means the only one and IMHO not the best. If you look for
>instance on Creasy/Resnik's "Maternal-Fetal Medicine" page 839.
>Renal Function studies
>"Uric acid is the most sensitive indicator of pre-eclampsia available to
>clinicians---------"
>4th edition 1999.
>
> Abstract
>
> OBJECTIVE: This study was undertaken to investigate the utility
> of an admission battery of findings and laboratory data in the
> discrimination of patients with severe preeclampsia with or
> without HELLP (hemolysis, elevated liver enzyme levels, and
> low platelet count) syndrome at high risk for development of
> significant maternal morbidity.
>
> STUDY DESIGN: The clinical and laboratory findings at hospital
> admission for 970 patients with severe preeclampsia with or
> without HELLP syndrome were studied retrospectively to
> develop parameters associated with low, moderate, and high
> risks for the subsequent development of significant maternal
> morbidity involving the hematologic and coagulation,
> cardiopulmonary, and hepatorenal systems.
>
> RESULTS: Nausea and vomiting and epigastric pain are
> independent risk factors for complicated severe preeclampsia.
>Results of a panel of tests with values including lactate dehydrogenase
>level >1400 IU/L, aspartate aminotransferase level >150 IU/L, alanine
>aminotransferase level >100 IU/L, uric acid level >7.8 mg/dL, serum
>creatinine level >1.0 mg/dL, and 4+ urinary protein by dipstick can be
>used to discriminate the patient at high risk for significant maternal
>morbidity. Concentrations of lactate dehydrogenase, aspartate
>aminotransferase, and uric acid above these cut points have the
>strongest predictive value and are risk additive with worsening
>thrombocytopenia.
>
>CONCLUSION: The presence of nausea and vomiting,
>epigastric pain, or both in association with admission
>laboratory values that are in excess of the cutoffs for
>lactate dehydrogenase, aspartate aminotransferase, and
>uric acid concentrations or for all 6 tests is predictive of
>high risk of morbidity for the patient with severe
>preeclampsia. These factors are independent of and
>additive with the rising maternal risk associated with
>decreasing platelet
>
>Ron-- there are a lot more articles supporting the use of uric acid as
>one of the values you must look for adequate assesment. I finished my
>training in 1977 -- I am still learning.
>
>At Thu, 2 Mar 2000, ainsron@msn.com wrote:
>>
>>I agree with you that uric acid is almost always elevated in
>>pre-eclampsia, due to changes in glomerular filtration. This has been
>>recognized since long before any of us were practicing obsetrics.
>>However, even Williams Obstetrics points out that this elevation is
>>"generally of little practical value for diagnosis, management or
>>prognosis." Like many other discussions on this list have pointed out,
>>we often do things because of habit and training that have little
>>supporting data.
>>
>>>At Thu, 2 Mar 2000, ainsron@msn.com wrote:
>>>>>Even though we were taught in residency (1975-79) that uric acid is a marker of pre-eclampsia, when did it ever make a difference in how you clinically handle a patient?<<
>>>
>>>I disagree. There are many patients with a clinical picture which may
>>>be compatible with preeclampsia yet the signs, symptoms and lab values
>>>are not indicative. In those circumstances one needs all the help one
>>>can get in order to make the proper diagnosis. Serum uric acid and
>>>urinary calcium excretion are both tests which have helped me personally
>>>make clinical decisions. For example; urinary calcium excretion in
>>>normal pregnancy is approximately 350-600 mg/volume. Patients with
>>>preeclampsia often have values <40 mg/volume. Very few condition will
>>>lead to such a decrease in calcium excretion. I have found uric acid to
>>>be of assistance in helping with the diagnosis in an otherwise confusing
>>>case. I have been fortunate enough to train and practice in a
>>>geographic are with a high incidence of preeclampsia/eclampsia. Believe
>>>me, these two tests help. Perhaps in a private OB practice with middle
>>>class patients and a low incidence of preeclampsia they may not be as
>>>helpful.
>>>
>>>LSR
>>
>>--
>>Ronald E. Ainsworth, MD
>>
>--
>"The things you learn after you know everything are the important ones"
>
--
art fougner, md
A series of 1000 cases begins with but a single anecdote.
