552
The
Refeeding Syndrome
To the Editor: Solomon and Kirby’ in their review of the refeeding syndrome, described G-3-PD as a phosphorylated compound that is depleted when serum phosphorus levels are low. G-3-PD (glyceraldehyde-3-phosphate dehydrogenase) is an enzyme using inorganic phosphorus as a cofactor. When serum phosphorus levels are low, the activity of the enzyme is diminished but the concentration of the enzyme is not necessarily modified. The reduced enzyme activity leads to a limited formation of 2,3-DPG and ATP.2 The enzyme is not phosphorylated during the oxidative phosphorylation of glyceraldehyde3-phosphate3 so the reduced activity does not result from a diminution of the phosphorylated enzyme. I would also like to make a comment on the inclusion of hyporeflexia as a common manifestation of hypomagnesemia. The majority of authors4-6 do not even cite hyporeflexia among the signs of hypomagnesemia, including the reference’ quoted by Solomon and Kirby. The symptoms and signs of hypomagnesemia are confounded by the association with disturbances of the acidbase status and of other electrolytes. Hyporeflexia has been described in 1969 by Shils’ in two of his seven patients but normo- or hyperreflexia have also been
reported.
caught a transcription error with regard to hypomagnesemia and hyporeflexia. While hyporeflexia has been reported by Shils’ in 1969, as Dr. Mass6 points out, hyperreflexia is generally more common, and the correct reference’ was inadvertantly deleted from our list. We thank Dr. Mass6 for discovering this error and appreciate the opportunity to correct it. DONALD F. KIRBY, M.D. SCOTT S. SOLOMON, M.D. Medical College of Virginia
He has also
Richmond, VA
REFERENCES 1. Shils ME:
Experimental
human
magnesium depletion. Medicine
48:61-85, 1969 2. Reinhart RA: Magnesium metabolism: A review with special reference to the relationship between intracellular content and serum levels. Arch Intern Med 148:2415-2420, 1988
No Shortcuts To
Height
M.D.
JACQUES MASSÉ, Service de Biochimie Hôpital Hôtel-Dieu de Montréal Montréal, Quebec, Canada H2W 1 T8 REFERENCES 1. Solomon 2.
3.
4.
SM, Kirby DF. The refeeding syndrome: A review. JPEN 14:90-97, 1990 Travis SF, Sugerman HJ, Ruberg RL, et al: Alterations of red cell glycolytic intermediates and oxygen transport as a consequence of hypophosphatemia in patients receiving intravenous hyperalimentation. N Engl J Med 285:763-768, 1971 Kawato RM, Caswell AH. Autophosphorylation of glyceraldehydephosphate dehydrogenase and phosphorylation of protein from skeletal muscle microsomes. Biochemistry 25:656-661, 1986 Knochel JP: Neuromuscular manifestations of electrolyte disor-
ders. Am J Med 72:521-535, 1982 5. Elin RJ: Magnesium metabolism in health and disease. Disease-aMonth 44:166-218, 1988 6. Kingston ME, Al-Siba ’I MB, Skooge WC: Clinical manifestations of hypomagnesemia. Crit Care Med 14:950-954, 1986 7. Alpers DH, Clouse RE, Stenson WF: Minerals. IN Manual of Nutritional Therapeutics, Alpers DH, Clouse RE, Stenson WF (eds). 2nd ed. Little Brown, Boston, 1988, pp 92-93 8. Shils ME: Experimental human magnesium depletion. Medicine 48:61-85, 1969
Response
to Dr Massé’s Letter
To the Editor: We appreciate Dr. Masse’s clarification that G-3-PD is an enzyme and agree with his comments on this issue.
To the Editor: Height and weight-for-height measurements identify risk for chronic and acute nutrition depletion in the pediatric patient.’ An individual’s growth pattern plotted on the smoothed growth curves from National Center for Health Statistics can demonstrate usual or unusual progress.’ Growth chart guidelines recommend that proper technique be used for comparison with the reference data.’ Percentile changes occur with variances of even 1 to 2 cm. Important variables for measuring and plotting height include the child’s posture and placement on the instrument, reading the height measurement level, the correct age and sex of the child, accurate recording, and the measuring instrument itself. With only one stadiometer on our unit limited access was considered a factor to the problem of a lack of patient height measurements. To increase availability inexpensive, plastic measuring devices with right angle headpieces were placed in 19 patient rooms. We reviewed the accuracy of these instruments after three months of use. A chart review (n 300) revealed height measurements had been taken on all the patients admitted to the pediatric unit. A 60-cm calibrated template (Holtain Ltd, Britain) was used as the standard and measured three times on each device by the same person. The variance of three measurements from individual devices was very low (p = 1). This indicated with careful technique the measurements were reproducible from the same instrument. The variance of measurements from different devices compared to the ideal (60 cm) was greater at 1.2 cm ((SD ±-
Downloaded from pen.sagepub.com at Purdue University on April 13, 2015
=
The
Refeeding Syndrome
To the Editor: Solomon and Kirby’ in their review of the refeeding syndrome, described G-3-PD as a phosphorylated compound that is depleted when serum phosphorus levels are low. G-3-PD (glyceraldehyde-3-phosphate dehydrogenase) is an enzyme using inorganic phosphorus as a cofactor. When serum phosphorus levels are low, the activity of the enzyme is diminished but the concentration of the enzyme is not necessarily modified. The reduced enzyme activity leads to a limited formation of 2,3-DPG and ATP.2 The enzyme is not phosphorylated during the oxidative phosphorylation of glyceraldehyde3-phosphate3 so the reduced activity does not result from a diminution of the phosphorylated enzyme. I would also like to make a comment on the inclusion of hyporeflexia as a common manifestation of hypomagnesemia. The majority of authors4-6 do not even cite hyporeflexia among the signs of hypomagnesemia, including the reference’ quoted by Solomon and Kirby. The symptoms and signs of hypomagnesemia are confounded by the association with disturbances of the acidbase status and of other electrolytes. Hyporeflexia has been described in 1969 by Shils’ in two of his seven patients but normo- or hyperreflexia have also been
reported.
caught a transcription error with regard to hypomagnesemia and hyporeflexia. While hyporeflexia has been reported by Shils’ in 1969, as Dr. Mass6 points out, hyperreflexia is generally more common, and the correct reference’ was inadvertantly deleted from our list. We thank Dr. Mass6 for discovering this error and appreciate the opportunity to correct it. DONALD F. KIRBY, M.D. SCOTT S. SOLOMON, M.D. Medical College of Virginia
He has also
Richmond, VA
REFERENCES 1. Shils ME:
Experimental
human
magnesium depletion. Medicine
48:61-85, 1969 2. Reinhart RA: Magnesium metabolism: A review with special reference to the relationship between intracellular content and serum levels. Arch Intern Med 148:2415-2420, 1988
No Shortcuts To
Height
M.D.
JACQUES MASSÉ, Service de Biochimie Hôpital Hôtel-Dieu de Montréal Montréal, Quebec, Canada H2W 1 T8 REFERENCES 1. Solomon 2.
3.
4.
SM, Kirby DF. The refeeding syndrome: A review. JPEN 14:90-97, 1990 Travis SF, Sugerman HJ, Ruberg RL, et al: Alterations of red cell glycolytic intermediates and oxygen transport as a consequence of hypophosphatemia in patients receiving intravenous hyperalimentation. N Engl J Med 285:763-768, 1971 Kawato RM, Caswell AH. Autophosphorylation of glyceraldehydephosphate dehydrogenase and phosphorylation of protein from skeletal muscle microsomes. Biochemistry 25:656-661, 1986 Knochel JP: Neuromuscular manifestations of electrolyte disor-
ders. Am J Med 72:521-535, 1982 5. Elin RJ: Magnesium metabolism in health and disease. Disease-aMonth 44:166-218, 1988 6. Kingston ME, Al-Siba ’I MB, Skooge WC: Clinical manifestations of hypomagnesemia. Crit Care Med 14:950-954, 1986 7. Alpers DH, Clouse RE, Stenson WF: Minerals. IN Manual of Nutritional Therapeutics, Alpers DH, Clouse RE, Stenson WF (eds). 2nd ed. Little Brown, Boston, 1988, pp 92-93 8. Shils ME: Experimental human magnesium depletion. Medicine 48:61-85, 1969
Response
to Dr Massé’s Letter
To the Editor: We appreciate Dr. Masse’s clarification that G-3-PD is an enzyme and agree with his comments on this issue.
To the Editor: Height and weight-for-height measurements identify risk for chronic and acute nutrition depletion in the pediatric patient.’ An individual’s growth pattern plotted on the smoothed growth curves from National Center for Health Statistics can demonstrate usual or unusual progress.’ Growth chart guidelines recommend that proper technique be used for comparison with the reference data.’ Percentile changes occur with variances of even 1 to 2 cm. Important variables for measuring and plotting height include the child’s posture and placement on the instrument, reading the height measurement level, the correct age and sex of the child, accurate recording, and the measuring instrument itself. With only one stadiometer on our unit limited access was considered a factor to the problem of a lack of patient height measurements. To increase availability inexpensive, plastic measuring devices with right angle headpieces were placed in 19 patient rooms. We reviewed the accuracy of these instruments after three months of use. A chart review (n 300) revealed height measurements had been taken on all the patients admitted to the pediatric unit. A 60-cm calibrated template (Holtain Ltd, Britain) was used as the standard and measured three times on each device by the same person. The variance of three measurements from individual devices was very low (p = 1). This indicated with careful technique the measurements were reproducible from the same instrument. The variance of measurements from different devices compared to the ideal (60 cm) was greater at 1.2 cm ((SD ±-
Downloaded from pen.sagepub.com at Purdue University on April 13, 2015
=
